Posted tagged ‘model’

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.

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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)

Cloning My Ghost Again

March 19, 2010

Here are more cloning images I did in     2009.  In the picture to the left I tried to have an “interactive”argument of showing “who” had a bigger muscle and where. I did realize my mistake of “bicep” me looking at “leg” me at the wrong angle, but how do you really correct that?

This was my attempt at “adding” more of me into a framed shot. The biggest difficulty I have faced when “posing” these shots is the lack of depth and space afforded by my stage. Since this is done in my living room, there is only so much of it that I can show that is not cluttered or “busy” with furniture or hanging framed pictures. Yes I “photoshopped” my tummy to give myself a less fat look but hey, who wouldn’t if you know how. I do also realize that the look of one of my clones and the angle makes it look a little “happy” but that was TOTALLY unintentional. I was going for the look of “look at that idiot” but it just didn’t happen.

This cloning happened during the NFL playoffs and I was attempting at a roleplaying shot. I used my AFL Carolina Cobras jersey I won at an auction and my old high school practice jersey to pull this off. Right off the bat, I had problems due to the framing of the stage and the placement of the center’s hand is off. Although everything is to scale, it would “appear” that my center’s rear is way too big and in the Qb’s face



Cloning My Ghost

March 13, 2010

Sometimes when you see my artwork(print stuff), you’ll notice that it is a bit dated. Is it a fault of my own? Sure, I haven’t had a “real” art class since high school, and even then it was my sophmore year in ’89.  I did have art classes at the School of Communication Arts, however I don’t think drawing a nude model constitutes enhancing of my art skill. Anyway, not to get off on a sidebar and this first ever blog is not about that, I wanted to show you a new photoshop skill I learned last year and have been trying to improve on since. Ghosting or cloning ; the art of creating several images of one’s self in the same photograph. I was looking up tutorials on photoshop and I stumbled upon this and thought that it would be cool to try.

The first attempt: I was watching a Carolina football game and they were losing at that point so during halftime I put my digital camera on my daughter’s Playskool table and shot this. I tried to use an interactive style shot but the main problem was that I was wearing the same outfit. I just felt that I didn’t get the whole effect of what I was going for in this shot. It did take me 1/2 hour to take and edit this photo though.

The 2nd Attempt: This time I definitly made sure to make it look like I was wearing different clothes (except I saw later that I didn’t change shorts) Same set up on the table as before. I just could not figure out a good pose.

3rd Attempt: One of my better attempts at double cloning with interaction was this playstation bit. I made sure that I had completely different clothes on and used a prop. I don’t remember entirely but I think my wifey asked why all those clothes were in a pile in the living room when she got home.

 4th Attempt: This time I wanted to try and up the ante and do some overlapping, this was a little difficult for me since you had to get the depth right or it wouldn’t work. I did a few other double clonings but by far these four examples turned out the best.

 

SEMPER FI!