Archive for May 2010

Development of Aerial Combat in World War II

May 30, 2010

Fighter development slowed between World War I and II, with the most significant change coming late in the period, when the classic World War I type machines started to give way to metal monocoque or semi-monocoque monoplanes, with cantilever wing structures. Given limited defense budgets, air forces tended to be conservative in their aircraft purchases, and biplanes remained popular with pilots because of their agility. Designs such as the Gloster Gladiator, Fiat CR.42, and Polikarpov I-15 were common even in the late 1930s, and many were still in service as late as 1942. Up until the mid-1930s, the vast majority of fighter aircraft remained fabric-covered biplanes. Fighter armament eventually began to be mounted inside the wings, outside the arc of the propeller, though most designs retained two synchronized machine-guns above the engine (which were considered more accurate). Rifle-caliber guns were the norm, with .50 caliber machine guns and 20 mm cannons deemed “overkill.” Considering that many aircraft were constructed similarly to World War I designs (albeit with aluminum frames), it was not considered unreasonable to use World War I-style armament to counter them. There was insufficient aerial combat during most of the period to disprove this notion.

The rotary engine, popular during World War I, quickly disappeared, replaced chiefly by the stationary radial engine. Aircraft engines increased in power several-fold over the period, going from a typical 180 hp in the 1918 Fokker D.VII to 900 hp in the 1938 Curtiss P-36. The debate between the sleek in-line engines versus the more reliable radial models continued, with naval air forces preferring the radial engines, and land-based forces often choosing in-line units. Radial designs did not require a separate (and vulnerable) cooling system, but had increased drag. In-line engines often had a better power-to-weight ratio, but there were radial engines that kept working even after having suffered significant battle damage.

Some air forces experimented with “heavy fighters” (called “destroyers” by the Germans). These were larger, usually a two- engine aircraft, sometimes adaptations of light or medium bomber types. Such designs typically had greater internal fuel capacity (thus longer range) and heavier armament than their single-engine counterparts. In combat, they proved ungainly and vulnerable to more nimble single-engine fighters.

The primary drive for fighter innovation, right up to the period of rapid rearmament in the late thirties, was not military budgets, but civilian aircraft races. Aircraft designed for these races pioneered innovations like streamlining and more powerful engines that would find their way into the fighters of World War II.

At the very end of the inter-war period came the Spanish Civil War. This was just the opportunity the German Luftwaffe, Italian Regia Aeronautica, and the Soviet Union’s Red Air Force needed to test their latest aircraft designs. Each party sent several aircraft to back their side in the conflict. In the dogfights over Spain, the latest Messerschmitt fighters (Bf 109) did well, as did the Soviet Polikarpov I-16. The German design, however, had considerable room for development and the lessons learned in Spain led to greatly improved models in World War II. The Russians, whose side lost in the conflict, nonetheless determined that their planes were sufficient for their immediate needs. I-16s were later slaughtered en masse by these improved German models in World War II, although they remained the most common Soviet front-line fighter until well into 1942. For their part, the Italians were satisfied with the performance of their Fiat CR.42 biplanes, and being short on funds, continued with this design even though it was obsolescent. The Spanish Civil War also provided an opportunity for updating fighter tactics. One of the innovations to result from the aerial warfare experience this conflict provided was the development of the “finger-four” formation by the German pilot Werner Mölders. Each fighter squadron (German: Staffel) was divided into several flights (Schwärme) of four aircraft. Each Schwarm was divided into two Rotten ,which was a pair of aircraft. Each Rotte was composed of a leader and a wingman. This flexible formation allowed the pilots to maintain greater situational awareness, and the two Rotte could split up at any time and attack on their own. The finger-four would become widely adopted as the fundamental tactical formation over the course of World War II.

Aerial combat formed an important part of World War II military doctrine. The ability of aircraft to locate, harass, and interdict ground forces was an instrumental part of the German combined-arms doctrine, and their inability to achieve air superiority over Britain made a German invasion unfeasible. German Field Marshal Erwin Rommel noted the effect of airpower: “Anyone who has to fight, even with the most modern weapons, against an enemy in complete command of the air, fights like a savage against modern European troops, under the same handicaps and with the same chances of success.”

During the 1930s, two different streams of thought about air-to-air combat began to emerge, resulting in two different approaches to monoplane fighter development. In Japan and Italy especially, there continued to be a strong belief that lightly armed, highly maneuverable single-seat fighters would still play a primary role in air-to-air combat. Aircraft such as the Nakajima Ki-27, Nakajima Ki-43 and the Mitsubishi A6M Zero in Japan, and the Fiat G.50 and Macchi C.200 in Italy epitomized a generation of monoplanes designed to this concept.

The other stream of thought, which emerged primarily in Britain, Germany, the Soviet Union, and the United States was the belief that the high speeds of modern combat aircraft and the g-forces imposed by aerial combat meant that dogfighting in the classic World War I sense would be impossible. Fighters such as the Messerschmitt Bf 109, the Supermarine Spitfire, the Yakovlev Yak-1 and the Curtiss P-40 Warhawk were all designed for high level speeds and a good rate of climb. Good maneuverability was desirable, but it was not the primary objective.

The 1939 Soviet-Japanese Battle of Khalkhyn Gol and the initial German invasion of Poland that same year were too brief to provide much feedback to the participants for further evolution of their respective fighter doctrines. During the Winter War, the greatly outnumbered Finnish Air Force, which had adopted the German finger-four formation, bloodied the noses of Russia’s Red Air Force, which relied on the less effective tactic of a three-aircraft delta formation.

European theater (Western Front)

The Battle of France, however, gave the Germans ample opportunity to prove they had mastered the lessons learned from their experiences in the Spanish Civil War. The Luftwaffe, with more combat-experience pilots and the battle-tested Messerschmitt Bf 109 fighter operating in the flexible finger-four formation, proved superior to its British and French contemporaries relying on the close, three-fighter “vic” (or “V”) and other formations, despite their flying fighters with comparable maneuver performance.

The Battle of Britain was the first major military campaign to be fought entirely by air forces, and it offered further lessons for both sides. Foremost was the value of radar for detecting and tracking enemy aircraft formations, which allowed quick concentration of fighters to intercept them farther from their targets. As a defensive measure, this ground-controlled interception (GCI) approach allowed the Royal Air Force (RAF) to carefully marshal its limited fighter force for maximum effectiveness. At times, the RAF’s Fighter Command achieved interception rates greater than 80%.

In the summer of 1940, then Flight Lieutenant Adolph Malan introduced a variation of the German formation that he called the “fours in line astern”, which spread into more general use throughout Fighter Command. In 1941, Squadron Leader Douglas Bader adopted the “finger-four” formation itself, giving it its English-language name.

The Battle of Britain also revealed inadequacies of extant tactical fighters when used for long-range strategic attacks. The twin-engine heavy fighter concept was revealed as a failed concept as the Luftwaffe’s heavily armed but poorly maneuverable Messerschmitt Bf 110s proved highly vulnerable to nimble Hurricanes and Spitfires; the Bf 110s were subsequently relegated to night fighter and fighter-bomber roles for which they proved better-suited. Furthermore, the Luftwaffe’s Bf 109s, operating near the limits of their range, lacked endurance for prolonged dogfighting over Britain. When bomber losses induced Reichsmarschall Hermann Göring to assign most fighters to close-in escort duties, forcing them to fly and maneuver at reduced speeds, German fighter effectiveness fell and losses rose.

The Allies themselves, however, would not learn this latter lesson until they sustained heavy bomber losses of their own during daylight raids against Germany. Despite the early assertions of strategic bombing advocates that “the bomber will always get through”, even heavily armed U.S. Army Air Force (USAAF) bombers like the Boeing B-17 Flying Fortress and Consolidated B-24 Liberator suffered such high losses to German fighters (such as the Focke-Wulf Fw 190 “bomber destroyer”) and flak (AAA) that – following the second raid on Schweinfurt in August 1943 – the U.S. Eighth Air Force was forced to suspend unescorted bombing missions into Germany until longer-range fighters became available for escort. These would appear in the form of Lockheed P-38 Lightnings, Republic P-47 Thunderbolts and North American P-51 Mustangs. The use of drop tanks also became common, which further made the heavy twin-engine fighter designs redundant, as single-engine fighters could now cover a similar distance. Extra fuel was carried in lightweight aluminum tanks below the aircraft, and the tanks were discarded when empty. Such innovations allowed American fighters to range over Germany and Japan by 1944.

As the war progressed, the growing numbers of these advanced, long-range fighters flown by pilots with increasing experience eventually overwhelmed their German opposition, despite the Luftwaffe’s introduction of technological innovations like jet- and rocket-powered interceptors. The steady attrition of experienced pilots forced the Germans to more frequently dip into their training pool to make up numbers when casualties surged. While new Allied airmen in Europe were well-trained, new Luftwaffe pilots were seldom able to get effective training – particularly by the summer of 1944, when Allied fighters often loitered around their airfields. Luftwaffe training flights were additionally hampered by the increasingly acute fuel shortages that began in April 1944.

European theater (Eastern Front)

On the Eastern Front, the strategic surprise of Operation Barbarossa demonstrated that Soviet air defense preparations were woefully inadequate, and the Great Purge rendered any lessons learned by the Red Air Force command from previous experience in Spain and Finland virtually useless. During the first few months of the invasion, Axis air forces were able to destroy large numbers of Red Air Force aircraft on the ground and in one-sided dogfights. However, by the winter of 1941–1942, the Red Air Force was able to put together a cohesive air defense of Moscow, successfully interdict attacks on Leningrad, and begin production of new aircraft types in the relocated semi-built factories in the Urals, Siberia, Central Asia and the Caucasus. These facilities produced more advanced monoplane fighters, such as the Yak-1, Yak-3, LaGG-3, and MiG-3, to wrest air superiority from the Luftwaffe. However, Soviet aircrew training was hasty in comparison to that provided to the Luftwaffe, so Soviet pilot losses continued to be disproportionate until a growing number of survivors were matched to more effective machines.

Beginning in 1942, significant numbers of British, and later U.S., fighter aircraft were also supplied to aid the Soviet war effort, with the Bell P-39 Airacobra proving particularly effective in the lower-altitude combat typical of the Eastern Front. Also from that time, the Eastern Front became the largest arena of fighter aircraft use in the world; fighters were used in all of the roles typical of the period, including close air support, interdiction, escort and interception roles. Some aircraft were armed with weapons as large as 45 mm cannon (particularly for attacking enemy armored vehicles), and the Germans began installing additional smaller cannons in under-wing pods to assist with ground-attack missions.

Pacific theatre

In the Pacific Theater, the experienced Japanese used their latest Mitsubishi A6M “Zero” to clear the skies of all opposition. Allied air forces – often flying obsolete aircraft, as the Japanese were not deemed as dangerous as the Germans – were caught off-guard and driven back until the Japanese became overextended. While the Japanese entered the war with a cadre of superbly trained airmen, they were never able to adequately replace their losses with pilots of the same quality, resulting in zero leave for experienced pilots and sending pilots with minimal skill into battle, while the British Commonwealth Air Training Plan and U.S. schools produced thousands of competent airmen, compared to hundred the Japanese graduated a year before the war. Japanese fighter planes were also optimized for agility and range, and in time Allied airmen developed tactics that made better use of the superior armament and protection in their Grumman F4F Wildcats and Curtiss P-40s. From mid-1942, newer Allied fighter models were faster (Wildcat was 13 mph slower than the Zero, but the Warhawk was 29 mph faster) and better-armed than the Japanese fighters. Improved tactics such as the Thach weave helped counter the more agile Zeros and Nakajima Ki-43 ‘Oscars’. Japanese industry was not up to the task of mass-producing fighter designs equal to the latest Western models, and Japanese fighters had been largely driven from the skies by mid-1944.

Technological innovations

Piston-engine power increased considerably during the war. The Curtiss P-36 Hawk had a 900 hp (670 kW) radial engine but was soon redesigned as the P-40 Warhawk with a 1100 hp (820 kW) in-line engine. By 1943, the latest P-40N had a 1300 hp (970 kW) Allison engine. At war’s end, the German Focke-Wulf Ta 152 interceptor could achieve 2050 hp (1530 kW) with an MW-50 (methanol-water injection) supercharger and the American P-51H Mustang fitted with the Packard V-1650-9 could achieve 2218 hp (1650 kW) under war emergency power. The Spitfire Mk I of 1939 was powered by a 1030 hp (770 kW) Merlin II; its 1945 successor, the Spitfire F.Mk 21, was equipped with the 2035 hp (1520 kW) Griffon 61. Likewise, the radial engines favored for many fighters also grew from 1,100 hp (820 kW) to as much as 2090 hp (770 kW) during the same timeframe.

The first turbojet-powered fighter designs became operational in 1944, and clearly outperformed their piston-engined counterparts. New designs such as the Messerschmitt Me 262 and Gloster Meteor demonstrated the effectiveness of the new propulsion system. (Rocket-powered interceptors – most notable the Messerschmitt Me 163 – appeared at the same time, but proved less effective.) Many of these fighters could do over 660 km/h in level flight, and were fast enough in a dive that they started encountering the transonic buffeting experienced near the speed of sound; such turbulence occasionally resulted in a jet breaking up in flight due to the heavy load placed on an aircraft near the so-called “sound barrier”. Dive brakes were added to jet fighters late in World War II to minimize these problems and restore control to pilots.

More powerful armament became a priority early in the war, once it became apparent that newer stressed-skin monoplane fighters could not be easily shot down with rifle-caliber machine guns. The Germans’ experiences in the Spanish Civil War led them to put 20 mm cannons on their fighters. The British soon followed suit, putting cannons in the wings of their Hurricanes and Spitfires. The Americans, lacking a native cannon design, instead chose to place multiple .50 caliber (12.7 mm) machine guns on their fighters. Armaments continued to increase over the course of the war, with the German Me 262 jet having four 30 mm cannons in the nose. Cannons fired explosive shells, and could blast a hole in an enemy aircraft rather than relying on kinetic energy from a solid bullet striking a critical subsystem (fuel line, hydraulics, control cable, pilot, etc.). A debate existed over the merits of high rate-of-fire machine guns versus slower-firing, but more devastating, cannon.

With the increasing need for close air support on the battlefield, fighters were increasingly fitted with bomb racks and used as fighter-bombers. Some designs, such as the German Fw 190, proved extremely capable in this role – though the designer Kurt Tank had designed it as a pure interceptor. While carrying air-to-surface ordnance such as bombs or rockets beneath the aircraft’s wing, its maneuverability is decreased because of lessened lift and increased drag, but once the ordnance is delivered (or jettisoned), the aircraft is again a fully capable fighter aircraft. By their flexible nature, fighter-bombers offer the command staff the freedom to assign a particular air group to air superiority or ground-attack missions, as need requires.

Rapid technology advances in radar, which had been invented shortly prior to World War II, would permit their being fitted to some fighters, such as the Messerschmitt Bf 110, Bristol Beaufighter, de Havilland Mosquito, Grumman F6F Hellcat and Northrop P-61 Black Widow, to enable them to locate targets at night. The Germans developed several night-fighter types as they were under constant night bombardment by RAF Bomber Command. The British, who developed the first radar-equipped night fighters in 1940–1941, lost their technical lead to the Luftwaffe. Since the radar of the era was fairly primitive and difficult to use, larger two- or three-seat aircraft with dedicated radar operators were commonly adapted to this role.

Advertisements

My Memorial Day

May 29, 2010

It was pitch black outside and all I could hear was the crashing of the waves on Gold Beach. I closed my eyes, trying to hear the chatter of the machine guns as the spit out fire towards the growing waves of human flesh clawing their way forward.Opening my eyes again, I tried to imagine rows of landing craft rushing towards me. Yet all I could see was the lights of a French fishing trawler, lazily bouncing through the water.  It was 1987, and I was 13 years old. I had come to Europe that fall on my family’s version of the National Lampoon European Vacation (yes we did get caught in a traffic circle in Paris going 6 times around before exiting). Six countries in 14 days and roughly 2000 miles worth of driving. Although I have many “firsts” accomplished during this trip, the only thing I wanted to see was this span of beach.

If you are my age, or older, you’ll remember that our introductions to World War II, were through films made in the 50’s, 60’s, and 70’s. Tora, Tora, Tora…Sands of Iwo Jima…the Longest Day, were all done in black and white. Nothing was computer generated and the special effects were primitive.  The only thing I requested from my parents during this trip was to be taken to the Normandy Beaches.  I wanted to see what those thousands of soldiers saw on that fateful day of June 6th 1944. I started out at Gold beach and the next day I went to Omaha and Utah beaches. Standing on Omaha beach, I could only imagine the enormity of the task that those grunts went through.  The German pillboxes are empty but they still bore the signs of the intense fighting that took place. Shell markings and bullet holes still remain, along with a beached burnt out landing craft still there. I went to the National Cemetary nearby and although I didn’t see an old guy collapse crying near Capt. Miller’s grave (movie Saving Private Ryan), I will never forget the hundreds of rows of crosses and the eerily quiet sound I experienced.  I went to Arnhem and tried to figure out what they meant by a Bridge too Far.  Funny how, years later,I can understand the German being spoken in those movies without having to utilize the subtitles.

When I was 8 years old, I went to Pearl Harbor. There is a rule that states that persons younger than 6 could not go to the Arizona Memorial. I actually witnessed two groups of elderly gentlemen, one American, the other Japanese get into a heated argument and tussel while I stood there trying to imagine that there were over 1000 men entombed below me. I’ve been to the Bridge of the river Kwai (it’s a mile and half away from the original) and have even seen the British fortress in Singapore.  I’ve stood on the walls of Fort Macon thinking how absurd it was that they felt secure not thinking they could be flanked from the “land” side.  I stood on the earthen walls of Fort Fisher trying to imagine how it took the US Marines 4 tries to finally defeat the fort. I’ve even stood inside the Baltimore Harbor looking towards Fort McHenry and knowing that the British felt like fools for not being able to take it.

History. Most of you absolutely hated the subject in high school, and avoided it in college. A subject taught so watered down, you couldn’t tell me who was the US president after Abe Lincoln was assissinated BUT you could tell me how many seasons American Idol has been on and who won the 3rd one. History is often fueled by people’s passion and interpreted incorrectly the same way. For me history is simply the event. We all know that the twin towers in New York City were brought down. That is the event, it cannot be disputed. What cannot be agreed upon is, who did it.  Anyway, I feel I was just about to go on a tangent so let me get back to the subject.

Here are the cold hard facts. I was born in the United States.  I was born in Texas and raised in North Carolina. By default, making me a Southerner. I enlisted into the US Marine Corps at age 18.  Watching movies, reading books, and traveling to different historical landmarks has made me wholely appreciate the sacrifices of many generations of Americans that lived before me. You cannot step on places like Gettysburg and not feel the enormous sadness  of entire bloodlines being wiped out with one volley of 58 calibre musket fire. While at the same time knowing that as Americans, they fought and stood up for what they believed in. For me, that was enough. I felt that for a country to give “me” such liberties and freedoms, I should feel obligated to repay them, even if it meant my life.

I guess I had always wanted to be a Marine since I saw my uncle in his Dress Blues at age 4.  I said that would be me one day.  In high school, I latched onto the visiting Marine recruiters making sure that I wanted in real bad. I was a two sport athlete and ready for any challenges that lay ahead. Then Iraq invaded Kuwait in my senior year and it was on…This was my chance, go fight for my country and repay my blood debt.  It of course was not meant to be…It was over in 100 hours and I still had 4 months till graduation. My uncle was killed in an accident at Quantico, two days after I turned 18. I never looked back.  My mother cried on the telephone when she found out, my father was just pissed because he wanted me to go to college.  I bent a little and and did both. I made it through literally by the skin of my toenails and earned the coveted title Marine.

For me, 8 1/2 years was literally boring.  I was a Marine during the Clinton era. Not much going on and the only excitement was getting orders to Somalia.  I did however fulfill another promise.  My unit was based out of Raleigh North Carolina. A 330 man supply unit with nothing (really) to do during training weekends.  I got into a little trouble due to the monotony of it all and decided to be a better Marine by joining the color guard.  So every month, my little detail would go down to the capital(NC) area and participate in the POW/MIA ceremony at the Vietnam Memorial.  This ceremony is simply where participants would read off all the dead and missing Carolina natives from the Vietnam War. After years of being the port rifleman, I actually was promoted to the NCOIC of this ceremony. Other times we’d participate in parades throughout the region, including strangely enough a Cinco de Mayo parade. Marine Corps Balls were always my favorite and even events that had camera crews filming inches from your face.  Funerals were often taxing due to having to be stone faced yet compassionate towards the grieving families. For me though, it was an honor, being bestowed by strangers to allow me to help lay to rest, a warrior that went before me.  I remember every single funeral I did in those 8 1/2 years. I don’t remember every name or even one name. To me though, that was history.

I remember is high school how the school newspaper found out that I was pro Helms(Helms vs. Gantt race), pro war, and joining the Marine Corps after graduation.  I had countless people approaching me after the “sound byte” and berating me and chastising me for my opinions.  I never backed down and interestingly enough, 3 of my friends actually joined the Navy after graduation. Your are damn right I point that out everytime it comes up too. I am absolutely appalled at most Americans for their views on practically everyting.  During Desert Shield/Desert Storm we had “everyone” flying the American flag from their car antennae trying to “bury” the ghosts of Vietnam. As quickly as it appeared, the faux patriotism quickly disappeared with me constantly getting fussed out by parents ,when calling an applicant’s home  while on recruiting duty, because there was no way their son was going into the military. The one thing that annoys me to this day is someone finding out you were in the service and saying,” Well I was gonna join but (fill in the blank)….” It doesn’t make me respect you nor does it make me connect with you. If you are one of those types…just don’t do it. I was honorably discharged in 2000. Obviously the events of 9/11 happened. Afghanistan and Iraq now have US forces in them. There yet again was the reemergence of faux patriotism…instead of flags on cars, we had magnetic yellow ribbons. That sooned disappeared when it was popular to hate Bush and to hear people say,”I support the Troops, but don’t support the War.” Newsflash: Soldiers and Marines don’t like to hear this statement b/c in reality, you don’t support them at all. There are countless anti war protests with former soldiers and Marines (some in wearing their former uniform) taking place even today. Although these same individuals served their country, they’ve lost sight of what it meant to serve their country, choosing instead to say that their country “lied to them”.  This is not honoring your brother that has sacrificed and gone before you. You cannot mix politics and military service while in uniform.

I have friends that suffer from PTSD and are alcoholics due to what they’ve seen and been through. The thing is, they know the risks. Suicide rate is up high, there is no money to treat every case to PTSD at the VA. Barracks are in shambles. I knew Marines that were on food stamps and working at pizza delivery places after work, just to have some extra money. Yet peoples’ political passions are strong and their support for the military man, weak.

My whole point in this is, it’s another Memorial Day. When they play the National Anthem at whatever ballpark you are going to this weekend, take your hat off, shut up, and stand still for those 2 1/2 minutes. If you run into a veteran and are truly thankful for his service, give him a strong handshake and say thanks. Say a prayer to whatever God you worship and thank him for giving you ancestors that stood up and fought for that 93% lean beef patty your grilling out on the Weber. If you don’t know much about your own family, research it. You might find that your great great granddad made a stand at Little Round Top or shot down a Japanese fighter defending the USS Nevada during the attack on Pearl Harbor. I believe in God, County, the Corps. I believe in defending the Constituition of the United States. I believe in fighting for and upholding the rights of all “American” citizens, even when I don’t share their views. I made a difference. Those are who I will always remember on Memorial Day. All Gave Some, Some Gave All.
Semper Fi!

Biting Off More Than One Can Chew

May 18, 2010

A man who lives at Lake Conroe  (50 miles north of Houston ) saw a ball bouncing around strangely on the surface of the lake and went to investigate.

It turned out to be a flathead catfish that had  apparently tried to eat a basketball, which then became stuck in its mouth. The fish was almost exhausted from trying to dive.It was unable to, because the buoyancy of the ball would always bring him back up to the surface.

The man tried unsuccessfully to simply take the ball out.


So, his wife cut the ball in order to deflate the ball to release the hungry catfish.

You probably wouldn’t have believed this story,
If you didn’t see the following pictures:

Remember to be kinder than necessary

Because everyone bites off more

Than they can chew sometime in life….

B-25 : The Pistol Packing Bomber

May 16, 2010

B-25 Mitchell

The North American B-25 Mitchell was an American twin-engined medium bomber manufactured by North American Aviation. It was used by many Allied air forces, in every theater of World War II, as well as many other air forces after the war ended, and saw service across four decades.The B-25 was named in honor of General Billy Mitchell, a pioneer of U.S. military aviation. The B-25 is the only American military aircraft named after a specific person. By the end of its production, nearly 10,000 B-25s in numerous models had been built. These included a few limited variations, such as the United States Navy’s and Marine Corps’ PBJ-1 patrol bomber and the United States Army Air Forces’ F-10 photo reconnaissance aircraft.

Design and development

Flight Performance School also included work in evaluating the performance of this B-25 Mitchell medium bomberThe B-25 was a descendant of the earlier XB-21 (North American-39) project of the mid-1930s. Experience gained in developing that aircraft was eventually used by North American in designing the B-25 (called the NA-40 by the company). One NA-40 was built, with several modifications later being done to test a number of potential improvements. These improvements included Wright R-2600 radial engines, which would become standard on the later B-25.

In 1939, the modified and improved NA-40B was submitted to the United States Army Air Corps for evaluation. This aircraft was originally intended to be an attack bomber for export to the United Kingdom and France, both of which had a pressing requirement for such aircraft in the early stages of World War II. However, those countries changed their minds, opting instead for the also-new Douglas DB-7 (later to be used by the US as the A-20 Havoc). Despite this loss of sales, the NA-40B re-entered the spotlight when the Army Air Corps evaluated it for use as a medium bomber. Unfortunately, the NA-40B was destroyed in a crash on 11 April 1939. Nonetheless, the type was ordered into production, along with the Army’s other new medium bomber, the Martin B-26 Marauder.

Early production

An improvement of the NA-40B, dubbed the NA-62, was the basis for the first actual B-25. Due to the pressing need for medium bombers by the Army, no experimental or service-test versions were built. Any necessary modifications were made during production runs, or to existing aircraft at field modification centers around the world.A significant change in the early days of B-25 production was a re-design of the wing. In the first nine aircraft, a constant-dihedral wing was used, in which the wing had a consistent, straight, slight upward angle from the fuselage to the wing tip. This design caused stability problems, and as a result, the dihedral angle was nullified on the outboard wing sections, giving the B-25 its slightly gull wing configuration. Less noticeable changes during this period included an increase in the size of the tail fins and a decrease in their inward cant.A total of 6,608 B-25s were built at North American’s Fairfax Airport plant in Kansas City, Kansas.A descendant of the B-25 was the North American XB-28, meant to be a high-altitude version of the B-25. Despite this premise, the actual aircraft bore little resemblance to the Mitchell. It had much more in common with the B-26 Marauder.

Operational history

The B-25 first gained fame as the bomber used in the 18 April 1942 Doolittle Raid, in which sixteen B-25Bs led by the legendary Lieutenant Colonel Jimmy Doolittle, attacked mainland Japan four months after the bombing of Pearl Harbor. The mission gave a much-needed lift in spirits to the Americans, and alarmed the Japanese who had believed their home islands were inviolable by enemy troops. While the amount of actual damage done was relatively minor, it forced the Japanese to divert troops for the home defense for the remainder of the war. The raiders took off from the carrier USS Hornet and successfully bombed Tokyo and four other Japanese cities without loss. However, 15 subsequently crash-landed en route to recovery fields in Eastern China. These losses were the result of the task force being spotted by Japanese fishing vessels forcing the bombers to take off 170 mi early, fuel exhaustion, stormy nighttime conditions with zero visibility, and lack of electronic homing aids at the recovery bases. Only one landed intact; it came down in the Soviet Union, where its five-man crew was interned and the aircraft confiscated. Of the 80 aircrew, 69 survived their historic mission and eventually made it back to American lines.Following a number of additional modifications, including the addition of Plexiglas windows for the navigator and radio operator, heavier nose armament, and deicing and anti-icing equipment, the B-25C was released to the Army. This was the second mass-produced version of the Mitchell, the first being the lightly-armed B-25B used by the Doolittle Raiders. The B-25C and B-25D differed only in location of manufacture: -Cs at Inglewood, California, -Ds at Kansas City, Kansas. A total of 3,915 B-25Cs and -Ds were built by North American during World War II.

Although the B-25 was originally designed to bomb from medium altitudes in level flight, it was used frequently in the Southwest Pacific theater (SWPA) on treetop-level strafing and parafrag (parachute-retarded fragmentation bombs) missions against Japanese airfields in New Guinea and the Philippines. These heavily-armed Mitchells, field-modified at Townsville, Australia, by Major Paul I. “Pappy” Gunn and North American tech rep Jack Fox, were also used on strafing and skip-bombing missions against Japanese shipping trying to re-supply their land-based armies. Under the leadership of Lieutenant General George C. Kenney, B-25s of the Fifth and Thirteenth Air Forces devastated Japanese targets in the SWPA from 1942 to 1945, and played a significant role in pushing the Japanese back to their home islands. B-25s were also used with devastating effect in the Central Pacific, Alaska, North Africa, Mediterranean and China-Burma-India theaters.Because of the urgent need for hard-hitting strafer aircraft, a version dubbed the B-25G was developed, in which the standard-length transparent nose and the bombardier were replaced by a shorter solid nose containing two fixed .50 in machine guns and a 75 mm M4 cannon, one of the largest weapons fitted to an aircraft, similar to the experimental British Mosquito Mk. XVIII, and German Ju 88P heavy cannon carrying aircraft. The cannon was manually loaded and serviced by the navigator, who was able to perform these operations without leaving his crew station just behind the pilot. This was possible due to the shorter nose of the G-model and the length of the M4, which allowed the breech to extend into the navigator’s compartment.

The B-25G’s successor, the B-25H, had even more firepower. The M4 gun was replaced by the lighter T13E1, designed specifically for the aircraft. The 75 mm gun fired at a muzzle velocity of 2,362 ft/s . Due to its low rate of fire (approximately four rounds could be fired in a single strafing run) and relative ineffectiveness against ground targets, as well as substantial recoil, the 75 mm gun was sometimes removed from both G and H models and replaced with two additional .50 in machine guns as a field modification. The -H also mounted four fixed forward-firing .50 machine guns in the nose, four more fixed ones in forward-firing cheek blisters, two more in the top turret, one each in a pair of new waist positions, and a final pair in a new tail gunner’s position. Company promotional material bragged the B-25H could “bring to bear 10 machine guns coming and four going, in addition to the 75 mm cannon, a brace of eight rockets and 3,000 lb of bombs.”

The B-25H also featured a redesigned cockpit area, with the top turret moved forward to the navigator’s compartment (thus requiring the addition of the waist and tail gun positions), and a heavily modified cockpit designed to be operated by a single pilot, the co-pilot’s station and controls deleted, and the seat cut down and used by the navigator/cannoneer, the radio operator being moved to the aft compartment, operating the waist guns. A total of 1,400 B-25Gs and B-25Hs were built.

The final version of the Mitchell, the B-25J, looked much like the earlier B, C and D, having reverted to the longer nose. The less-than-successful 75 mm cannon was deleted on the J model. Instead, 800 of this version were built with a solid nose containing eight .50 machine guns, while other J-models featured the earlier “greenhouse” style nose containing the bombardier’s position. Regardless of the nose style used, all J-models also included two .50 in guns in a “fuselage package” located directly under the pilot’s station, and two more such guns in an identical package just under the co-pilot’s compartment. The solid-nose B-25J variant carried an impressive total of 18 .50 in guns: eight in the nose, four in under-cockpit packages, two in an upper turret, two in the waist, and a pair in the tail. No other bomber of World War II carried as many guns. However, the first 555 B-25Js (the B-25J-1-NC production block) were delivered without the fuselage package guns, because it was discovered muzzle blast from these guns was causing severe stress in the fuselage;this was cured with heavier fuselage skin patches, while later production runs returned these guns, they were often removed as a field modification for the same reason. In all, 4,318 B-25Js were built.

The B-25 was a safe and forgiving aircraft to fly. With an engine out, 60° banking turns into the dead engine were possible, and control could be easily maintained down to 145 mph . However, the pilot had to remember to maintain engine-out directional control at low speeds after take off with rudder – if this was attempted with ailerons, the aircraft would snap out of control. The tricycle landing gear made for excellent visibility while taxiing. The only significant complaint about the B-25 was the extremely high noise level produced by its engines; as a result, many pilots eventually suffered from various degrees of hearing loss. The high noise level was due to design and space restrictions in the engine cowlings which resulted in the exhaust “stacks” protuding directly from the cowling ring and partly covered by a small triangular fairing. This directed exhaust and noise directly at the pilot and crew compartments. Crew members and operators on the airshow circuit frequently comment that “the B-25 is the fastest way to turn aviation fuel directly into noise”. Many B-25’s now in civilian ownership have been modified with exhaust rings that direct the exhaust through the outboard bottom section of the cowling.

The Mitchell was also an amazingly sturdy aircraft and could withstand tremendous punishment. One well-known B-25C of the 321st Bomb Group was nicknamed “Patches” because its crew chief painted all the aircraft’s flak hole patches with high-visibility zinc chromate paint. By the end of the war, this aircraft had completed over 300 missions, was belly-landed six times and sported over 400 patched holes. The airframe was so bent, straight-and-level flight required 8° of left aileron trim and 6° of right rudder, causing the aircraft to “crab” sideways across the sky.

An interesting characteristic of the B-25 was its ability to extend range by using one-quarter wing flap settings. Since the aircraft normally cruised in a slightly nose-high attitude, about 40 gal of fuel was below the fuel pickup point and thus unavailable for use. The flaps-down setting gave the aircraft a more level flight attitude, which resulted in this fuel becoming available, thus slightly extending the aircraft’s range.

By the time a separate United States Air Force was established in 1947, most B-25s had been consigned to long-term storage. However, a select number continued in service through the late 1940s and 1950s in a variety of training, reconnaissance and support roles. Its principal use during this period was for undergraduate training of multi-engine aircraft pilots slated for reciprocating engine or turboprop cargo, aerial refueling or reconnaissance aircraft. Still others were assigned to units of the Air National Guard in training roles in support of F-89 Scorpion and F-94 Starfire operations. TB-25J-25-NC Mitchell, 44-30854, the last B-25 in the USAF inventory, assigned at March AFB, California as of March 1960[6], was flown to Eglin AFB, Florida, from Turner Air Force Base, Georgia, on 21 May 1960, the last flight by a USAF B-25, and presented by Brig. Gen. A. J. Russell, Commander of SAC’s 822nd Air Division at Turner AFB, to the Air Proving Ground Center Commander, Brig. Gen. Robert H. Warren, who in turn presented the bomber to Valparaiso, Florida Mayor Randall Roberts on behalf of the Niceville-Valparaiso Chamber of Commerce. Four of the original Tokyo Raiders were present for the ceremony, Col. Davy Jones, Col. Jack Simms, Lt. Col. Joseph Manske, and retired Master Sgt. Edwin W. Horton. Donated back to the Air Force Armament Museum circa 1974 and marked as Doolittle’s 40-2344.

Empire State Building incident

On Saturday, 28 July 1945, at 0940 (while flying in thick fog), a USAAF B-25D crashed into the north side of the Empire State Building, hitting between the 79th and 80th floor. Fourteen people were killed — 11 in the building, along with Colonel William Smith and the other two occupants of the bomber. Betty Lou Oliver, an elevator attendant, survived the impact and a subsequent accident with the elevator. It was partly because of this incident that towers 1 and 2 of the World Trade Center were designed to withstand the impact of a Boeing 707 aircraft (unfortunately NOT Arab terrorist hijacked airliners).

Variants

B-25

The first version of the B-25 delivered. No prototypes were ordered. The first nine aircraft were built with constant dihedral angle. Due to low stability, the wing was redesigned so that the dihedral was eliminated on the outboard section. (Number made: 24.)
B-25A
Version of the B-25 modified to make it combat ready; additions included self-sealing fuel tanks, crew armor, and an improved tail gunner station. No changes were made in the armament. Re-designated obsolete (RB-25A designation) in 1942. (Number made: 40.)
B-25B
Rear turret deleted; manned dorsal and remotely-operated ventral turrets added, each with a pair of .50 in (12.7 mm) machine guns. The ventral turret was retractable, but the increased drag still reduced the cruise speed by 30 mph (48 km/h). 23 were delivered to the RAF as the Mitchell Mk I. The Doolittle Raiders flew B-25Bs on their famous mission. (Number made: 120.)
B-25C
Improved version of the B-25B: powerplants upgraded from Wright R-2600-9 radials to R-2600-13s; de-icing and anti-icing equipment added; the navigator received a sighting blister; nose armament was increased to two .50 in (12.7 mm) machine guns, one fixed and one flexible. The B-25C model was the first mass-produced B-25 version; it was also used in the United Kingdom (as the Mitchell II), in Canada, China, the Netherlands, and the Soviet Union. First mass-produced B-25 model. (Number made: 1,625.)
ZB-25C
B-25D
Identical to the B-25C, the only difference was that the B-25D was made in Kansas City, Kansas, whereas the B-25C was made in Inglewood, California. First flew on 3 January 1942. (Number made: 2,290.)
ZB-25D
XB-25E
Single B-25C modified to test de-icing and anti-icing equipment that circulated exhaust from the engines in chambers in the leading and trailing edges and empennage. The aircraft was tested for almost two years, beginning in 1942; while the system proved extremely effective, no production models were built that used it prior to the end of World War II. Many prop aircraft today use the XB-25E system. (Number made: 1, converted.)
ZXB-25E
XB-25F-A
Modified B-25C that tested the use of insulated electrical de-icing coils mounted inside the wing and empennage leading edges as a de-icing system. The hot air de-icing system tested on the XB-25E was more practical. (Number made: 1, converted.)
XB-25G
Modified B-25C in which the transparent nose was replaced by a solid one carrying two fixed .50 in (12.7 mm) machine guns and a 75 mm (2.95 in) M4 cannon, then the largest weapon ever carried on an American bomber. (Number made: 1, converted.)
B-25G
To satisfy the dire need for ground-attack and strafing aircraft, the B-25G was made following the success of the prototype XB-25G. The production model featured increased armor and a greater fuel supply than the XB-25G. One B-25G was passed to the British, who gave it the name Mitchell II that had been used for the B-25C. (Number made: 420.)
B-25H

B-25H Barbie III taxiing at Centennial Airport, ColoradoAn improved version of the B-25G. It featured two additional fixed .50 in (12.7 mm) machine guns in the nose and four in fuselage-mounted pods; the heavy M4 cannon was replaced by a lighter 75 mm (2.95 in) T13E1. (Number made: 1,000; number left flying in the world: 1.)
B-25J
The last production model of the B-25, often called a cross between the B-25C and the B-25H. It had a transparent nose, but many of the delivered aircraft were modified to have a solid nose. Most of its 14–18 machine guns were forward-facing for strafing missions. 316 were delivered to the Royal Air Force as the Mitchell III. (Number made: 4,318.)
CB-25J
Utility transport version.
VB-25J
A number of B-25s were converted for use as staff and VIP transports. Henry H. Arnold and Dwight D. Eisenhower both used converted B-25Js as their personal transports.

U.S. Navy / U.S. Marine Corps variants

PBJ-1C
Similar to the B-25C for the US Navy; often fitted with airborne search radar and used in the anti-submarine role.
PBJ-1D
Similar to the B-25D for the US Navy and US Marine Corps. Differed in having a single .50 in (12.7 mm) machine gun in the tail turret and beam gun positions similar to the B-25H. Often fitted with airborne search radar and used in the anti-submarine role.
PBJ-1G
US Navy/US Marine Corps designation for the B-25G
PBJ-1H
US Navy/US Marine Corps designation for the B-25H
PBJ-1J
US Navy designation for the B-25J-NC (Blocks -1 through -35) with improvements in radio and other equipment. Often fitted with “package guns” and wingtip search radar for the anti-shipping/anti-submarine role.

Survivors

There are more than one hundred surviving B-25 Mitchells scattered over the world, mainly in the United States. Most of them are on static display in museums, but about 45 are still airworthy.

On 18 April 2010, 17 airworthy B-25s took off from the airfield behind the National Museum of the United States Air Force and flew over in formation to commerate the 68th anniversary of the Doolittle Raid. Four of the surviving members of the Raid were in attendance for the reunion; Cole, Griffin, Hite and Thatcher, although Hite departed before the flyover. Secretary of the Air Force Michael Donley, Commander of Air Force Material Command General Donald Hoffman and the Director of the National Museum of the United States Air Force Major General Charles Metcalf were there also.

Specifications (B-25J)

North American B-25 Mitchell

Role Medium bomber

Manufacturer North American Aviation

First flight 19 August 1940

Introduction 1941

Retired 1979 (Indonesia)

Primary users United States Army Air Forces,Royal Canadian Air Force,Royal Air Force,Soviet Air Force

Number built 9,984

Developed from XB-21

Developed into North American XB-28

General characteristics

Crew: six (two pilots, navigator/bombardier, turret gunner/engineer, radio operator/waist gunner, tail gunner
Length: 52 ft 11 in (16.1 m)
Wingspan: 67 ft 6 in (20.6 m)
Height: 17 ft 7 in (4.8 m)
Wing area: 610 sq ft (57 m²)
Empty weight: 21,120 lb (9,580 kg)
Loaded weight: 33,510 lb (15,200 kg)
Max takeoff weight: 41,800 lb (19,000 kg)
Powerplant: 2× Wright R-2600 “Cyclone” radials, 1,850 hp (1,380 kW) each
Performance

Maximum speed: 275 mph (239 kn, 442 km/h)
Cruise speed: 230 mph (200 kn, 370 km/h)
Combat radius: 1,350 mi (1,170 nmi, 2,170 km)
Ferry range: 2,700 mi (2,300 nmi, 4,300 km)
Service ceiling: 25,000 ft (7,600 m)
Rate of climb: 790 ft/min (4 m/s)
Wing loading: 55 lb/ft² (270 kg/m²)
Power/mass: 0.110 hp/lb (182 W/kg)
Armament

Guns: 12-18 × .50 in (12.7 mm) machine guns
Hardpoints: 2,000 lb (900 kg) ventral shackles to hold one external Mark 13 torpedo[15]
Rockets: 3,000 lb (1,360 kg) bombs + eight 5 in (130 mm) high velocity aircraft rockets (HVAR)
Bombs: 6,000 lb (2,700 kg)

Stalking the Clouds: F7F Tigercat

May 13, 2010

F7F Tigercat

The Grumman F7F Tigercat was the first twin-engined fighter aircraft to enter service with the United States Navy. Designed for the new Midway-class aircraft carriers, the aircraft were too large to operate from earlier decks. Although delivered to United States Marine Corps combat units before the end of World War II, the Tigercat did not see combat service in that war. Most F7Fs ended up in land-based service, as attack aircraft or night fighters; only the later F7F-4N was certified for carrier service. They saw service in the Korean War and were withdrawn from service in 1954.

Design and development

Based on the earlier Grumman XP-50 that eventually was canceled, the company further developed the XP-65 (Model 51) for a future “convoy fighter” concept. In 1943, work on the XP-65 was terminated in favor of the design that would eventually become the F7F. The contract for the prototype XF7F-1 was signed on 30 June 1941. Grumman’s aim was to produce a fighter that out-performed and out-gunned all existing fighter aircraft, and that had an auxiliary ground attack capability. Armament was heavy: four 20 mm cannons and four 0.50 in machine guns, as well as underwing and under-fuselage hardpoints for bombs and torpedoes. Performance met expectations too; the F7F Tigercat was one of the highest-performance piston-engined fighters, with a top speed well in excess of the US Navy’s single-engined aircraft—71 mph faster than a F6F Hellcat at sea level. The opinion of Capt. Fred M. Trapnell, one of the Navy’s premier test pilots, was that “It’s the best damn fighter I’ve ever flown.”[4]The Grumman F7F was originally named the “Tomcat” but this name was rejected as it was considered at the time too suggestive. The name would much later be used for the Grumman F-14.All this was bought at the cost of heavy weight and a high landing speed, but what caused the aircraft to fail carrier suitability trials was poor directional stability with only one engine operational, as well as problems with the tail-hook design. Therefore, the initial production series was only used from land bases by the USMC, as night fighters with APS-6 radar. At first, they were single-seater F7F-1N aircraft, but after the 34th production aircraft, a second seat for a radar operator was added; these aircraft were designated F7F-2N. The next version produced, the F7F-3 was modified to correct the issues that caused the aircraft to fail carrier acceptance and this version was again trialled on the USS Shangri-La (CV-38). A wing failure on a heavy landing caused the failure of this carrier qualification too. F7F-3 aircraft were produced in day fighter, night fighter and photo-reconnaissance versions.A final version, the F7F-4N, was extensively rebuilt for additional strength and stability, and did pass carrier qualification, but only 12 were built.

Operational history

Marine Corps night fighter squadron VMF(N)-513 flying F7F-3N Tigercats saw action in the early stages of the Korean War, flying night interdiction and fighter missions and shooting down two Polikarpov Po-2 biplanes. This was the only combat use of the aircraft.
Most F7F-2Ns were modified to control drones for combat training, and these gained bubble canopies over the rear cockpit for the drone controller. A F7F-2D used for pilot transitoning also had a rear sliding, bubble canopy.In 1945, two Tigercats were evaluated, but rejected, by the British Royal Navy, preferring a navalized version of the de Havilland Hornet.

Variants

XF7F-1
Prototype aircraft, two built.
F7F-1 Tigercat
Twin-engine fighter-bomber aircraft, powered by two Pratt & Whitney R-2800-22W radial piston engines. First production version, 34 built.
F7F-1N Tigercat
Single-seat night fighter aircraft, fitted with an APS-6 radar.
XF7F-2N
Night-fighter prototype, One built.
F7F-2N Tigercat
Two-seat night fighter, 65 built.
F7F-2D
Small numbers of F7F-2Ns converted into drone control aircraft. The aircraft were fitted with an F8F Bearcat-windshield behind the     cockpit.
F7F-3 Tigercat
Single-seat fighter-bomber aircraft, powered by two Pratt & Whitney R-2800-34W radial piston engines, 189 built.
F7F-3N Tigercat
Two-seat night fighter aircraft, 60 built.
F7F-3E Tigercat
Small numbers of F7F-3s were converted into electronic warfare aircraft.
F7F-3P Tigercat
Small numbers of F7F-3s were converted into photo-reconnaissance aircraft.
F7F-4N Tigercat
Two-seat night-fighter aircraft, fitted with an arrester hook and other naval equipment, 13 built.

Operators

United States

* United States Marine Corps
* United States Navy

Survivors

Beginning in 1949, F7Fs were flown to the US Navy storage facility at Litchfield Park in Arizona. Although the vast majority of the airframes were eventually scrapped, a number of examples were purchased as surplus. The surviving Tigercats were primarily used as water bombers to fight forest fires in the 1960s and 1970s. A total of 12 examples exist today with six F7Fs remaining airworthy.
As warbird racers, in 1976, Robert Forbes qualified an F7F-3N but did not race at Reno. Another modified F7F-3N Tigercat, (Bu No. 80503) “Big Bossman” owned by Mike Brown presently competes in the national air racing circuit.

At least four F7F Tigercats are preserved in aviation museums:

* F7F-3 (Serial no. 80373/N7654C) National Museum of Naval Aviation, NAS Pensacola, Florida
* F7F-3 (Serial no. 80410) Pima Air & Space Museum, Tucson, Arizona
* F7F-3P (Serial no. 80390/N700F) Kalamazoo Aviation History Museum, Kalamazoo, Michigan
* An F7F (Model & Serial no. TBD) is maintained at the Historic Flight Foundation at Paine Field in Everett, Washington

Specifications (F7F-4N Tigercat)

General characteristics

Role     Fighter aircraft

Manufacturer     Grumman

First flight     2 November 1943

Introduced     1944

Retired     1954

Primary users     United States Navy, United States Marine Corps

Produced     1943–1946

Number built     364

* Crew: 2 (pilot, radar operator)
* Length: 45 ft 4 in (13.8 m)
* Wingspan: 51 ft 6 in (15.7 m)
* Height: 16 ft 7 in (5.1 m)
* Wing area: 455 ft² (42.3 m²)
* Empty weight: 16,270 lb (7,380 kg)
* Max takeoff weight: 25,720 lb (11,670 kg)
* Powerplant: 2× Pratt & Whitney R-2800-34W “Double Wasp” radial engines, 2,100 hp (1,566 kW) each


Performance

* Maximum speed: 460 mph (400 knots, 740 km/h)
* Range: 1,200 mi (1,000 nmi, 1,900 km)
* Service ceiling: 40,400 ft (12,300 m)
* Rate of climb: 4,530 ft/min (1,381 m/min)

Armament

* Guns:
o 4 × 20 mm (0.79 in) M2 cannon
o 4 × 0.50 in (12.7 mm) M2 Browning machine gun
* Bombs:
o 2 × 1,000 lb (454 kg) bombs under wings or
o 1 × torpedo under fuselage

Avionics

* AN/APS-19 radar

Predator : Silent Eye In The Sky

May 13, 2010

MQ-1 PREDATOR UNMANNED AERIAL VEHICLE

Mission

The MQ-1 Predator is a medium-altitude, long-endurance, remotely piloted aircraft. The MQ-1’s primary mission is interdiction and conducting armed reconnaissance against critical, perishable targets. When the MQ-1 is not actively pursuing its primary mission, it acts as the Joint Forces Air Component Commander-owned theater asset for reconnaissance, surveillance and target acquisition in support of the Joint Forces commander.

Features

The MQ-1 Predator is a system, not just an aircraft. A fully operational system consists of four aircraft (with sensors), a ground control station, a Predator Primary Satellite Link, and approximately 55 personnel for deployed 24-hour operations.The basic crew for the Predator is one pilot and two sensor operators. They fly the aircraft from inside the ground control station via a C-Band line-of-sight data link or a Ku-Band satellite data link for beyond line-of-sight flight. The aircraft is equipped with a color nose camera (generally used by the pilot for flight control), a day variable-aperture TV camera, a variable-aperture infrared camera (for low light/night), and a synthetic aperture radar for looking through smoke, clouds or haze. The cameras produce full motion video while the SAR produces still frame radar images.The MQ-1 Predator carries the Multi-spectral Targeting System with inherent AGM-114 Hellfire missile targeting capability and integrates electro-optical, infrared, laser designator and laser illuminator into a single sensor package. The aircraft can employ two laser-guided Hellfire anti-tank missiles with the MTS ball.The system is composed of four major components which can be deployed for worldwide operations. The Predator aircraft can be disassembled and loaded into a “coffin.” The ground control system is transportable in a C-130 (or larger) transport aircraft. The Predator can operate on a 5,000 by 75 feet (1,524 meters by 23 meters), hard surface runway with clear line-of-sight. The ground data terminal antenna provides line-of-sight communications for takeoff and landing. The PPSL provides over-the-horizon communications for the aircraft.An alternate method of employment, Remote Split Operations, employs a smaller version of the GCS called the Launch and Recovery GCS. The LRGCS conducts takeoff and landing operations at the forward deployed location while the CONUS based GCS conducts the mission via extended communications links.The aircraft includes an ARC-210 radio, an APX-100 IFF/SIF with Mode 4, an upgraded turbo-charged engine and glycol-weeping wet wings  for ice mitigation. The latest upgrade includes fuel injection, longer wings, dual alternators and other improvements.

Background

The “M” is the Department of Defense designation for multi-role and “Q” means unmanned aircraft system. The “1” refers to the aircraft being the first of a series of purpose-built remotely piloted aircraft systems.The Predator system was designed in response to a Department of Defense requirement to provide persistent intelligence, surveillance and reconnaissance information to the warfighter.In April 1996, the secretary of defense selected the U.S. Air Force as the operating service for the RQ-1 Predator system. A change in designation from “RQ-1” to “MQ-1” occurred in 2002 with the addition of the armed reconnaissance role.Operational squadrons are the 11th, 15th and 17th Reconnaissance Squadrons, Indian Springs Air Force Auxiliary Field, Nev.

General Characteristics

Primary Function: Armed reconnaissance, airborne surveillance and target acquisition
Contractor: General Atomics Aeronautical Systems Incorporated
Power Plant: Rotax 914 four cylinder engine producing 101 horsepower
Length: 27 feet (8.22 meters)
Height: 6.9 feet (2.1 meters)
Weight: 1,130 pounds ( 512 kilograms) empty, maximum takeoff weight 2,250 pounds (1,020 kilograms)
Wingspan: 48.7 feet (14.8 meters)
Speed: Cruise speed around 84 mph (70 knots), up to 135 mph
Range: up to 400 nautical miles (454 miles)
Ceiling: up to 25,000 feet (7,620 meters)
Fuel Capacity: 665 pounds (100 gallons)
Payload: 450 pounds (204 kilograms)
System Cost: $40 million (1997 dollars)
Initial operational capability: March 2005
Inventory: Active force, 57; ANG, 0; Reserve, 0

M1 Abrams: Tip of the Spear

May 9, 2010

 

The M1 Abrams is a third-generation main battle tank produced in the United States. The M1 is named after General Creighton Abrams, former Army Chief of Staff and Commander of US military forces in Vietnam from 1968 to 1972. It is a well armed, heavily armored, and highly mobile tank designed for modern armored ground warfare. Notable features of the M1 Abrams include the use of a powerful gas turbine engine, the adoption of sophisticated composite armor, and separate ammunition storage in a blow-out compartment for crew safety. It is one of the heaviest tanks in service, weighing in at close to 68 short tons (almost 62 metric tons).The M1 Abrams entered U.S. service in 1980, replacing the 105 mm gun, full tracked M60 Patton. It did, however, serve for over a decade alongside the improved M60A3, which had entered service in 1978. Three main versions of the M1 Abrams have been deployed, the M1, M1A1, and M1A2, incorporating improved armament, protection and electronics. These improvements, as well as periodic upgrades to older tanks have allowed this long-serving vehicle to remain in front-line service. The M1A3 is currently under development. It is the principal main battle tank of the United States Army and Marine Corps, and the armies of Egypt, Kuwait, Saudi Arabia, Australia, and in 2010 Iraq. The M1 Abrams is anticipated to be in U.S. service until the 2050s, approximately 70 years after entering U.S. service.

  History

 Development

 

The first attempt to replace the aging M60 tank was the MBT-70, developed in partnership with West Germany in the 1960s. The MBT-70 was very ambitious, and had various ideas that ultimately proved unsuccessful. As a result of the imminent failure of this project, the U.S. Army introduced the XM803. This succeeded only in producing an expensive system with capabilities similar to the M60.Congress canceled the MBT-70 in November and XM803 December 1971, and redistributed the funds to the new XM815 later renamed the XM1 Abrams after General Creighton Abrams. Prototypes were delivered in 1976 by Chrysler Defense and General Motors armed with the license-built version of the 105 mm Royal Ordnance L7 gun along with a Leopard 2 for comparison. The Chrysler Defense design was selected for development as the M1. In 1979, General Dynamics Land Systems Division purchased Chrysler Defense.3273 M1 Abrams were produced 1979-85 and first entered US Army service in 1980. It was armed with the license-built version of the 105 mm Royal Ordnance L7 gun. An improved model called the M1IP was produced briefly in 1984 and contained small upgrades. The M1IP models were used in the Canadian Army Trophy NATO tank gunnery competition in 1985 and 1987.About 6000 M1A1 Abrams were produced from 1986–92 and featured the M256 120 mm smoothbore cannon developed by Rheinmetall AG of Germany for the Leopard 2, improved armor, and a CBRN protection system. 

 Gulf War

 

As the Abrams entered service in the 1980s, they would operate alongside M60A3 within the United States military, and with other NATO tanks in numerous Cold War exercises. These exercises usually took place in Western Europe, especially West Germany, but also in some other countries like South Korea. During such training, Abrams crews honed their skills for use against the men and equipment of the Soviet Union. However, by 1991 the USSR had collapsed and the Abrams would have its trial by fire in the Middle East.The Abrams remained untested in combat until the Gulf War in 1991. A total of 1,848 M1A1s were deployed to Saudi Arabia. The M1A1 was superior to Iraq’s Soviet-era T-55 and T-62 tanks, as well as Iraqi-assembled Russian T-72s, and locally-produced copies (Asad Babil tank). The T-72s, like most Soviet export designs, lacked night vision systems and then-modern rangefinders, though they did have some night fighting tanks with older active infrared systems or floodlights—just not the latest starlight scopes and passive infrared scopes as on the Abrams. Only 23 M1A1s were taken out of service in the Gulf. Some others took minor combat damage, with little effect on their operational readiness. Very few Abrams tanks were hit by enemy fire, and there was only one fatality, along with a handful of woundings as a result.

The M1A1 was capable of making kills at ranges in excess of 2,500 metres (8,200 ft). This range was crucial in combat against tanks of Soviet design in Desert Storm, as the effective range of the main gun in the Soviet/Iraqi tanks was less than 2,000 metres (6,600 ft) . This meant Abrams tanks could hit Iraqi tanks before the enemy got in range—a decisive advantage in this kind of combat. In friendly fire incidents, the front armor and fore side turret armor survived direct APFSDS hits from other M1A1s. This was not the case for the side armor of the hull and the rear armor of the turret, as both areas were penetrated at least in two occasions by friendly DU ammunition during the Battle of Norfolk.

 

 Interwar upgrades

 

The M1A2 was a further improvement of the M1A1 with a commander’s independent thermal viewer and weapon station, position navigation equipment, digital data bus and a radio interface unit. The M1A2 SEP (System Enhancement Package) added digital maps, FBCB2 (Force XXI Battlefield Command Brigade and Below) capabilities, and an improved cooling system to maintain crew compartment temperature with the addition of multiple computer systems to the M1A2 tank.Further upgrades included depleted uranium armor for all variants, a system overhaul that returns all A1s to like-new condition (M1A1 AIM), a digital enhancement package for the A1 (M1A1D), a commonality program to standardize parts between the U.S. Army and the Marine Corps (M1A1HC) and an electronic upgrade for the A2 (M1A2 SEP).During Operations Desert Shield and Desert Storm and for Bosnia, some M1A1s were modified with armor upgrades. The M1 can be equipped with mine plow and mine roller attachments if needed. The M1 chassis also serves as a basis for the Grizzly combat engineering vehicle and the M104 Wolverine heavy assault bridge.Over 8,800 M1 and M1A1 tanks have been produced at a cost of US$2.35–$4.30 million per unit, depending on the variant. 

 Iraq War

 Further combat was seen during 2003 when US forces invaded Iraq and deposed the Iraqi leader Saddam Hussein. As of March 2005, approximately 80 Abrams tanks were forced out of action by enemy attacks. Nevertheless, the campaign saw very similar performance from the tank with no Abrams crew member being lost to hostile fire during the invasion of Iraq, although several tank crew members were later killed by roadside bombs during the occupation that followed.The most lopsided achievement of the M1A2s was the destruction of seven T-72 Lion of Babylon tanks in a point-blank skirmish (less than 50 yards ) near Mahmoudiyah, about 18 miles south of Baghdad, with no losses for the American side. In addition to the Abrams’ already heavy armament, some crews were also issued M136 AT4 shoulder-fired anti-tank weapons under the assumption that they might have to engage heavy armor in tight urban areas where the main gun could not be brought to bear.

 

Following lessons learned in Desert Storm, the Abrams and many other US combat vehicles used in the conflict were fitted with Combat Identification Panels to reduce friendly fire incidents. These were fitted on the sides and rear of the turret, with flat panels equipped with a four-cornered ‘box’ image on either side of the turret front . Some Abrams were also fitted with a secondary storage bin on the back of the existing bustle rack on the rear of the turret referred to as a bustle rack extension to enable the crew to carry more supplies and personal belongings.

 

Many Abrams (irrecoverable due to loss of mobility or other circumstances) were destroyed by friendly forces to prevent their capture, usually by other Abrams, who often found them very difficult to destroy despite their firepower.A majority of Abrams damaged post-invasion were by Improvised explosive devices.Some Abrams were disabled by Iraqi infantrymen in ambushes during the invasion. Some troops employed short-range anti-tank rockets and fired at the tracks, rear and top. Other tanks were put out of action when struck in critical places by heavy machine gun rounds.Due to the vulnerability of tanks in urban combat, the Tank Urban Survival Kit, or TUSK, is being issued to some M1 Abrams. It is intended to improve fighting ability in urban environments. 

 Future

The M1A3 Abrams is in the early design period with the U.S. Army. The Army aims to build prototypes by 2014 and to begin to field the first combat-ready M1A3s by 2017.

 

 Camouflage

 

Unlike earlier US military vehicles from World War II through Vietnam, which used a scheme of dark brownish green known as “olive drab” with large white stars, prototypes and early production M1 (105 mm gun) & M1-IP models used the flat medium green paint; and the large white insignia stars have transitioned to much smaller black markings. Some units painted their M1s with the older MERDC 4-color paint scheme but the turn-in requirements for these tanks required repainting them to solid green. Therefore, even though a large number of the base model M1s were camouflaged in the field, few or none exist today.M1A1s (120 mm gun) came from the factory with the NATO 3 color camouflage Black/Med-Green/Dark-Brown CARC paint jobs. Today M1A1s are given the NATO three color paint job during rebuilds. M1s and M1A1s deployed to Desert Storm were hastily painted desert tan. Some, but not all, of these tanks were re-painted to their “authorized” paint scheme. M1A2s built for Middle Eastern countries were painted in desert tan.Some M1 series tanks are being painted desert tan for service in Iraq and some are not. Replacement parts (roadwheels, armor skirt panels, drive sprockets, etc.) are painted overall green, which can sometimes lead to vehicles with a patchwork of green and desert tan parts.

 

 Concealment

 

The turret is fitted with two six-barreled smoke grenade launchers (USMC M1A1s use an eight-barreled version). These can create a thick smoke that blocks both vision and thermal imaging, and can also be armed with chaff. The engine is also equipped with a smoke generator that is triggered by the driver. When activated, fuel is sprayed on the engine manifold, creating the thick smoke. However, due to change from diesel as a primary fuel to the use of JP-8, this system is disabled on most Abrams today, because JP-8 causes the tanks to catch fire when sprayed on the manifold.

 

 Active protection system

In addition to the advanced armor, some Abrams are equipped with a Missile Countermeasure Device that can impede the function of guidance systems of semi-active control line-of-sight (SACLOS) wire and radio guided anti-tank missiles (Russian AT-3, AT-4, AT-5, AT-6 and the like) and thermally and infrared guided missiles (ATGM).[19] This device is mounted on the turret roof in front of the loader’s hatch, and can lead some people to mistake Abrams fitted with these devices for the M1A2 version, since the Commander’s Independent Thermal Viewer on the latter is mounted in the same place, though the MCD is box-shaped and fixed in place as opposed to cylindrical and rotating like the CITV.

 

 Armor

 

The Abrams is protected by armor based on the British-designed Chobham armor, a further development of the British ‘Burlington’ armor. Chobham is a composite armor formed by spacing multiple layers of various alloys of steel, ceramics, plastic composites, and kevlar, giving an estimated maximum (frontal turret) 1,320–1,620 millimetres (52–64 in) of RHAe versus HEAT (and other chemical energy rounds) and 940–960 mm (37–38 in) versus kinetic energy penetrators. It may also be fitted with reactive armor over the track skirts if needed (as in the Urban Survival Kit) and Slat armor over the rear of the tank and rear fuel cells to protect against ATGMs. Protection against spalling is provided by a Kevlar liner. Beginning in 1987, M1A1 tanks received improved armor packages that incorporated depleted uranium  mesh in their armor at the front of the turret and the front of the hull. Armor reinforced in this manner offers significantly increased resistance towards all types of anti-tank weaponry, but at the expense of adding considerable weight to the tank, as depleted uranium is 1.7 times more dense than lead.

 

The first M1A1 tanks to receive this upgrade were tanks stationed in Germany, since they were the first line of defense against the Soviet Union. US-based tank battalions participating in Operation Desert Storm received an emergency program to upgrade their tanks with depleted uranium armor immediately before the onset of the campaign. M1A2 tanks uniformly incorporate depleted uranium armor, and all M1A1 tanks in active service have been upgraded to this standard as well, the added protection from the depleted uranium armor is believed to be equivalent to 24 inches  of RHA. The strength of the armor is estimated to be about the same as similar western, contemporary main battle tanks such as the Leopard 2. In the Persian Gulf War, Abrams tanks survived multiple hits at relatively close ranges from Iraqi Lion of Babylon tanks and ATGMs. M829A1 “Silver Bullet” APFSDS rounds from other M1A1 Abrams were unable to penetrate the front and side armor (even at close ranges) in friendly fire incidents as well as an incident in which another Abrams tried to destroy an Abrams that got stuck in mud and had to be abandoned.

 

 Damage control

In the chance that the Abrams does suffer damage resulting in a fire in the crew compartment, the tank is equipped with a halon fire-suppression system that automatically engages and extinguishes fires in seconds.Fuel and ammunition are in armored compartments with blowout panels to protect the crew from the risk of the tank’s own ammunition cooking off if the tank is damaged.

 

 Armament

 Primary armament

M68A1 rifled gun

The main armament of the original model M1 was the M68A1 105 mm rifled tank gun firing a variety of high explosive anti-tank, high explosive, white phosphorus and an anti-personnel (multiple flechette) round. This gun is a license-built version of the British Royal Ordnance L7 gun. While being a reliable weapon and widely used by many NATO nations, a cannon with lethality beyond the 3-kilometer (1.9 mi) range was needed to combat newer armor technologies. To attain that lethality, projectile diameter needed to be increased. The M68A1’s performance in terms of accuracy and armor-piercing penetration is on par with the M256A1 up to 3 kilometers (1.9 mi) out, but beyond that range the 105 mm projectile lacks the kinetic energy to defeat modern armor packages.

M256 smoothbore gun

The main armament of the M1A1 and M1A2 is the M256A1 120 mm smoothbore gun, designed by Rheinmetall AG of Germany, manufactured under license in the United States by Watervliet Arsenal, New York. The M256A1 is a variant of the Rheinmetall 120 mm L/44 gun carried on the German Leopard 2 on all variants up to the Leopard 2A5. Leopard 2A6 replaced the L/44 barrel with a longer L/55.The M256A1 fires a variety of rounds. The M829A2 was developed specifically to address the threats posed by a Soviet T-90 or T-80U tank equipped with Kontakt-5 Explosive Reactive Armor. It also fires HEAT shaped charge rounds such as the M830, the latest version of which (M830A1) incorporates a sophisticated multi-mode electronic sensing fuse and more fragmentation which allows it to be used effectively against armored vehicles, personnel, and low-flying aircraft. The Abrams uses a manual loader, due to the belief that having a crewman reload the gun is faster and more reliable.[citation needed] and because autoloaders do not allow for separate ammunition storage in the turret.[citation needed] The fourth tank crewman on the Abrams also provides additional support for maintenance, observation post/listening post (LP/OP) operations, and other tasks.

The new M1028 120 mm anti-personnel canister cartridge was brought into service early for use in the aftermath of the 2003 invasion of Iraq. It contains 1,098 3⁄8-inch (9.5 mm) tungsten balls which spread from the muzzle to produce a shotgun effect lethal out to 600 meters (2,000 ft). The tungsten balls can be used to clear enemy dismounts, break up hasty ambush sites in urban areas, clear defiles, stop infantry attacks and counter-attacks and support friendly infantry assaults by providing covering fire. The canister round is also a highly effective breaching round and can level cinder block walls and knock man-sized holes in reinforced concrete walls for infantry raids at distances up to 75 meters (246 ft).

 

In addition to this, the new XM1111 (Mid-Range-Munition Kinetic Energy) is also in development. Essentially a cannon-fired guided round, it has a range of roughly 12 km and uses a KE warhead which is rocket assisted in its final phase of flight. This is intended to be the best penetrator yet, an improvement over the US 3rd generation DU penetrator (estimated penetration 790 mm (31 in)).

 

 Secondary armament

 

The Abrams tank has three machine guns:

 

A .50 cal. (12.7 mm) M2HB machine gun is in front of the commander’s hatch. On the M1, M1IP and M1A1, this gun is on a powered mount and can be fired using a 3× magnification sight, known as the Commander’s Weapon Station (CWS for short), while the vehicle is “buttoned up” with all its hatches closed to protect the crew. On the M1A2 & M1A2SEP, this gun is on a flex mount (seen at right), the Commander having to expose himself to fire the weapon manually. With the forthcoming TUSK addon kit, an M2HB or a Mk 19 grenade launcher can be mounted on the CROWS remote weapons platform (similar to the Protector M151 remote weapon station used on the Stryker family of vehicles). The upgrade variant called M1A1 Abrams Integrated Management (AIM) equips the .50 caliber gun with a thermal sight for accurate night and other low-visibility shooting.

A 7.62 mm M240 machine gun is in front of the loader’s hatch on a skate mount. Some of these have been fitted with gun shields during the ongoing conflict in Iraq as seen in the image at right, as well as night-vision scopes for low-visibility engagements.

A second 7.62 mm M240 machine gun is in a coaxial mount to the right of the main gun. The coaxial MG is aimed and fired with the same computer fire control system used for the main gun.

(Optional) A second coaxial 12.7 mm M2HB machine gun can be mounted directly above the main gun in a remote weapons platform as part of the TUSK upgrade kit.

For the US Army in previous years, the Abrams usually maintained the provision for storing an M16 rifle or M4 carbine inside the turret in case the crew is required to leave the tank under potentially hostile conditions; while the crewmen were supplied with the M9 Beretta pistol as a personal sidearm. Considering the current (often dismounted) role of American armored crewmen and contemporary operating environments, though, current US Army crews maintain a rifle or carbine for each crewman. During Iraqi Freedom some crews were also issued M136 AT4 shoulder-fired anti-tank weapons under the assumption that they might have to engage heavy armor in tight urban areas where the main gun could not be brought to bear.

 

 Aiming

 

The Abrams is equipped with a ballistic fire-control computer that uses user and system-supplied data from a variety of sources, to compute, display, and incorporate the three components of a ballistic solution – lead angle, ammunition type, and range to the target, to accurately fire the tank. These three components are determined using a YAG rod laser rangefinder, crosswind sensor, a pendulum static cant sensor, data concerning performance and flight characteristics of each specific type of round, tank-specific boresight alignment data, ammunition temperature, air temperature, barometric pressure, a muzzle reference system (MRS) that determines and compensates for barrel droop at the muzzle due to gravitational pull and barrel heating due to firing or sunlight, and target speed determined by tracking rate tachometers in the Gunner’s or Commander’s Controls Handles. All of these factors are computed into a ballistic solution and updated 30 times per second. The updated solution is displayed in the Gunner’s or Tank Commander’s field of view in the form of a reticle in both day and Thermal modes. The ballistic computer manipulates the turret and a complex arrangement of mirrors so that all one has to do is keep the reticle on the target and fire to achieve a hit. Proper lead and gun tube elevation are applied to the turret by the computer, greatly simplifying the job of the Gunner.The fire-control system uses these data to compute a firing solution for the gunner. The ballistic solution generated ensures a hit percentage greater than 95 percent at nominal ranges. Either the commander or gunner can fire the main gun. Additionally, the Commander’s Independent Thermal Viewer (CITV) on the M1A2 can be used to locate targets and pass them on for the gunner to engage while the commander scans for new targets. In the event of a malfunction or damage to the primary sight system, the main and coaxial weapons can be manually aimed using a telescopic scope boresighted to the main gun known as the Gunner’s Auxiliary Sight (GAS). The GAS has two interchangeable reticles; one for HEAT and MPAT (MultiPurpose AntiTank) rounds and one for APFSDS and STAFF (Smart Target-Activated Fire and Forget) ammunition. Turret traverse and main gun elevation can be accomplished with manual handles and cranks in the event of a Fire Control System or Hydraulic System failure. The commander’s M2 .50 caliber machine gun on the M1 and M1A1 is aimed by a 3x magnification sight incorporated into the Commander’s Weapon Station (CWS), while the M1A2 uses either the machine gun’s own iron sights, or a remote aiming system such as the CROWS system when used as part of the TUSK (Tank Urban Survival Kit). The loader’s M240 machine gun is aimed either with the built-in iron sights or with a thermal scope mounted on the machine gun.

 

 Mobility 

The M1 Abrams is powered by a 1,500 shaft horsepower (1,100 kW) Honeywell AGT 1500 (originally made by Lycoming) gas turbine, and a six speed (four forward, two reverse) Allison X-1100-3B Hydro-Kinetic automatic transmission, giving it a governed top speed of 45 mph (72 km/h) on paved roads, and 30 mph (48 km/h) cross-country. With the engine governor removed, speeds of around 60 mph (97 km/h) are possible on an improved surface; however, damage to the drive train (especially to the tracks) and an increased risk of injuries to the crew can occur at speeds above 45 mph (72 km/h). The tank for all intents and purposes was built around this engine.[26] The tank can be fueled with diesel fuel, kerosene, any grade of motor gasoline, JP-4 jet fuel, or JP-8 jet fuel; the US Army uses JP-8 jet fuel in order to simplify logistics. The Royal Australian Armoured Corps’ M1A1 AIM SA uses diesel fuel; it is cheaper and makes practical sense for Australian military logistics.

 

 

Driving controls the gas turbine propulsion system has proven quite reliable in practice and combat, but its high fuel consumption is a serious logistic issue (starting up the turbine alone consumes nearly 10 US gallons (38 l) of fuel).[27] The engine burns more than 1 US gallon (3.8 l) per mile and 12 US gallons (45 l) per hour when idle.[28] The high speed, high temperature jet blast emitted from the rear of M1 Abrams tanks makes it difficult for the infantry to proceed shadowing the tank in urban combat. The turbine is very quiet when compared to diesel engines of similar power output and produces a significantly different sound from a contemporary diesel tank engine, reducing the audible distance of the sound, thus earning the Abrams the nickname “whispering death” during its first REFORGER exercise.

 Honeywell was developing another gas turbine engine with General Electric for the XM2001 Crusader program that was also to be a replacement for the AGT-1500 engine already in the Abrams tank. The new LV100-5 engine is lighter and smaller (43% fewer parts) with rapid acceleration, quieter running and no visible exhaust. It also features a 33% reduction in fuel consumption (50% less when idle) and near drop-in replacement. The Abrams-Crusader Common Engine Program was shelved when the Crusader program was canceled, however Phase 2 of Army’s PROSE (Partnership for Reduced O&S Costs, Engine) program calls for further development of the LV100-5 and replacement of the current AGT-1500 engine. Future US tanks may return to reciprocating engines for propulsion, as 4-stroke diesel engines have proven quite successful in other modern heavy tanks, e.g. the Leopard 2, Challenger 2 and Merkava.Using a high power density 330 cc (20 cu in) Wankel rotary engine modified to use diesel and military grade jet fuel, TARDEC developed a 220-pound (100 kg) Auxiliary Power Unit designed to fit into the M1 Abrams, replacing an existing battery pack that weighs about 500 pounds (230 kg). The new APU will also be more fuel efficient. The installation of the first APUs is expected to start in 2009.

 

A provision exists that the Abrams be able to transport passengers in tank desant with the turret stabilization device off. One Infantry squad carrying only their battle gear may ride the rear of the turret. The soldiers have the option of using ropes and equipment straps as a field-expedient Infantry rail to provide handholds and snap links to secure themselves to the turret. The Squad leader, team leaders, grenadiers sit on the left and right sides of the turret, while the riflemen, and automatic riflemen sit at the rear. If and when enemy contact is made, the tank conceals itself allowing the infantry to dismount.

 

 Strategic mobility

 

Strategic mobility is the ability of the tanks of an armed force to arrive in a timely, cost effective, and synchronized fashion. The Abrams can be carried by a C-5 Galaxy or a C-17 Globemaster III. The limited capacity (two combat-ready in a C-5, one combat-ready tank in a C-17) caused serious logistical problems when deploying the tanks for the First Gulf War, though there was enough time for 1,848 tanks to be transported by ship.The Abrams is also transportable by truck, namely the M1070 Heavy Equipment Transporter (HET). The HET can operate on highways, secondary roads, and cross-country. The HET accommodates the 4 tank crewmen.

 

The government-owned Lima Army Tank Plant in Lima, Ohio, currently manufactures the Abrams, the Detroit Arsenal Tank Plant in Warren, Michigan manufactured it from 1982 to 1996. It costs upwards of US$5 million a tank

 

 Tank Urban Survival Kit

 The Tank Urban Survival Kit (TUSK), is a series of improvements to the M1 Abrams intended to improve fighting ability in urban environments. Historically, urban and other close battlefields have been the worst place for tanks to fight—a tank’s front armor is much stronger than that on the sides, top, or rear, and in an urban environment, attacks can come from any direction, and attackers can get close enough to reliably hit weak points in the tank’s armor, or get sufficient elevation to hit the top armor square on.Armor upgrades include reactive armor on the sides of the tank and slat armor (similar to that on the Stryker) on the rear to protect against rocket-propelled grenades and other shaped charge warheads.A Transparent Armor Gun Shield and a thermal sight system are added to the loader’s top-mounted M240B 7.62 mm machine gun, and a Kongsberg Gruppen Remote Weapon Turret carrying a .50 caliber machine gun (again similar to that used on the Stryker) is in place of the tank commander’s original .50 caliber machine gun mount, wherein the commander had to expose himself to fire the weapon manually. An exterior telephone allows supporting infantry to communicate with the tank commander.The TUSK system is a field-installable kit that allows tanks to be upgraded without needing to be recalled to a maintenance depot.While the reactive armor may not be needed in most situations in maneuver warfare, items like the rear slat armor, loader’s gun shield, infantry phone (which saw use on Marine Corps M1A1s as early as 2003), and Kongsberg Remote Weapons Station for the .50 caliber machine gun will be added to the entire M1A2 fleet over time.

 

On August 29, 2006, General Dynamics Land Systems received a US Army order for 505 Tank Urban Survivability Kits (TUSK) for Abrams main battle tanks supporting operations in Iraq, under a US$45 million contract. The add-on kit will be provided for M1A1 and M1A2-series tanks to enhance crew survivability in urban environments. The kit ordered by the Army consists of a Loader’s Armor Gun Shield (LAGS), a Tank Infantry Phone (TIP), Abrams Reactive Armor Tiles (ARAT), a Remote Thermal Sight (RTS) and a Power Distribution Box (PDB). Deliveries are expected to be complete by April 2009.

 

Under a separate order, the US Army awarded General Dynamics Armament and Technical Products (GDATP) US$30 million to produce reactive armor kits to equip M1A2. The total contract value could reach $59 million if all contract options are exercised. The reactive tiles for the M1 will be locally produced at GDATP’s Burlington Technology Center. Tiles will be produced at the company’s reactive armor facility in Stone County Operations, McHenry, Miss. On December 8, 2006 the U.S. Army added Counter Improvised Explosive Device enhancements to the M1A1 and M1A2 TUSK, awarding GDLS U.S. $11.3 million, part of the $59 million package mentioned above. In December GDLS also received an order amounting about 40% of a US$48 million order for loader’s thermal weapon sights being part of the TUSK system improvements for the M1A1 and M1A2 Abrams Tanks.

 

 Operators

 Australia – 59 M1A1SA (hybrids, mix equipment used by US.Army tanks and U.S.M.C. tanks, without DU layers in armor) tanks were bought from the United States in 2006, to replace the Leopard AS1 in 2007.

 Egypt – 1005 M1A1 (downgraded, without DU layers in armor) tanks co-produced by the USA and Egypt for the Egyptian army.

 Iraq – 140 M1A1M’s (downgraded, without DU layers in armor) on order, to be delivered by 2011. Currently 22 US.Army M1A1’s are leased for training.

 Kuwait – 218 M1A2s (downgraded, without DU layers in armor)

 Saudi Arabia – 373 eventually to be upgraded to M1A2S (without DU layers in armor)

 United States – Approximately 6,000 M1A1 and M1A2 variants including both Army and Marine Corps inventory + 3268 M1 and M1IP variants, not used in storage, waiting for upgrade to M1A2SEP variant (most of them) or rebuild to specialised vehicles.

1,174 M1A2 and M1A2SEP variants (Army inventory)

4,393 M1A1 variants (Army inventory). Under upgrade process to M1A1SA variant.

403 M1A1HC’s variants (Marine Corps inventory). Under upgrade process to M1A1FEP.

Type Main battle tank

Place of origin  United States

Service history

In service 1980–present
 
 
Production history

Designer Chrysler Defense
Manufacturer Lima Army Tank Plant (1980-present)
Detroit Arsenal Tank Plant (1982-1996)
Unit cost US$6.21 million (M1A2 / FY99)
Number built 9,000+
 
Specifications
 
Weight 67.6 short tons 
Length Gun forward: 32.04 ft
Hull length: 26.02 ft 
Width 12 ft 
Height 8 ft 
Crew 4 (commander, gunner, loader, driver)
 
Armor Chobham, RH armor, steel encased depleted uranium mesh plating
Primary armament 105 mm M68 rifled cannon (M1) 120 mm M256 smoothbore cannon (M1A1, M1A2, M1A2SEP))
Secondary armament 1 x .50-caliber  M2HB heavy machine gun
2 x 7.62 mm  M240 machine guns (1 pintle-mounted, 1 coaxial)
Engine Honeywell AGT1500C multi-fuel turbine engine
1,500 shp (1,120 kW)
Power/weight 24.5 hp/metric ton
Transmission Allison DDA X-1100-3B
Suspension Torsion bar
Ground clearance 1 ft 7 in (M1, M1A1) 1 ft 5 in (M1A2)
Fuel capacity 500 US gallons 
Operational range 289 mi With NBC system: 279 mi 
Speed Road: 42 mph Off-road: 30 mph