The Airco DH.4 was a British two-seat biplane day bomber of the First World War. It was designed by Geoffrey de Havilland (hence "DH") for Airco, and was the first British two-seat light day-bomber to have an effective defensive armament.
The DH.4 was developed as a light two-seat combat aircraft, intended to perform both aerial reconnaissance and day bomber missions. One of the early aims of the design was for it to be powered by the newly-developed Beardmore Halford Pullinger (BHP) engine, capable of generating up to 160 hp. During its first years of flight, it was tried with several different engines, perhaps the best of which was the 375 hp (280 kW) Rolls-Royce Eagle engine. Armament and ordnance for the aircraft consisted of one 0.303 in (7.7 mm) Vickers machine gun for the pilot and one 0.303 in (7.7 mm) Lewis gun on a Scarff ring mounting for the observer. In addition, either a pair of 230 lb (100 kg) bombs or a maximum payload of four 112 lb (51 kg) bombs could be carried.
The DH.4 performed its first flight in August 1916; less than a year later, it entered operational service in France on 6 March 1917 with No. 55 Squadron of the Royal Flying Corps (RFC). The majority of DH.4s were actually manufactured as general purpose two-seaters in the United States, the majority of which were intended to be used in service with the American expeditionary forces being deployed to fight in France. Following the signing of the Armistice of 11 November 1918, which effectively marked the end of the First World War, many DH.4s were determined to be surplus and sold, often to civil operators. Shortly after the conflict, the U.S. Army issued contracts to several companies to remanufacture many of their DH.4s to the improved DH.4B standard; and continued to operate the type into the early 1930s.
|DH.4 above the clouds in France|
|Role||Light bomber / General purpose|
|First flight||August 1916|
|Retired||1932 (United States Army Air Service)|
|Primary users||Royal Flying Corps|
Royal Air Force
Royal Naval Air Service
United States Army Air Service
|Number built||6,295, of which 4,846 were built in the United States.|
|Variants||DH.9, DH.9A, Dayton-Wright Cabin Cruiser|
The DH.4 was designed by Geoffrey de Havilland as a light two-seat combat aircraft, intended to perform both aerial reconnaissance and day bomber missions. An early feature of the design was the intention for it to be powered by the newly-developed Beardmore Halford Pullinger (BHP) engine, capable of generating up to 160 hp. According to aviation author J.M Bruce, the DH.4 was developed in parallel to the rival Bristol Fighter, developed and manufactured by the Bristol Aeroplane Company. During August 1916, the prototype DH.4 conducted the type's maiden flight, powered by a prototype BHP engine rated at 230 hp (170 kW).
Initial flight tests with the first prototype revealed it to have favourable handling and performance. The Central Flying School (CFS) conducted early evaluation flights using the prototype, leading to it producing a favourable report on the aircraft, observing its high stability in flight, light flying controls and its relatively comfortable crew positions. During its flights with the CFS, it was able to attain previously unheard-of time-to-altitude figures, unmatched by any of its predecessors. While flying trials with the prototype had been producing promising results, it soon became recognised that the BHP engine would have required a major redesign prior to the unit entering production.
Even by the time of flying trials with the first prototype, there had been no finalised plans for quantity production of the BHP engine. Coincidentally, another suitable and promising aeroengine, the water-cooled Rolls-Royce Eagle in-line engine, was approaching the end of its development process. According to Bruce, the Eagle shared the same basic configuration as the BHP engine, which greatly aiding in its adoption by de Havilland, as did the engine's endorsement by William Beardmore. During the summer of 1916, a second prototype, equipped with the Rolls-Royce engine, conducted its first flight.
In response to its favourable performance, the Royal Flying Corps (RFC) decided to place an initial order for the type during late 1916. Separately to the RFC's interactions with the DH.4, it had received substantial interest from the Royal Navy as well. The Admiralty decided to order a further pair of prototypes, configured to suit the service's own requirements, for evaluation purposes; however, according to Bruce, it is unlikely that the second of these was ever constructed. Following trials with the first of these prototypes, orders were placed for the production of DH.4s to equip the Royal Naval Air Service.
During late 1916, the first order for 50 DH.4s, powered by 250 hp (186 kW) Eagle III engines, was received from the RFC. According to Bruce, it was not a surprise to most observers that the Eagle had been selected to power the first batch of production DH.4s. The initial production aircraft were largely identical to the second prototype, the main difference being the adoption of armament, which included a single synchronised 0.303 in (7.7 mm) Vickers machine gun for the pilot, while the observer was provided with a 0.303 in (7.7 mm) Lewis gun mounted upon a Scarff ring.
Production of the DH.4 was performed by a variety of companies beyond Airco themselves; these included F.W. Berwick and Co, Glendower Aircraft Company, Palladium Autocars, Vulcan Motor and Engineering, and the Westland Aircraft Work. By the end of production, a total of 1,449 aircraft (from orders for 1,700 aircraft) were constructed in Britain for the Royal Flying Corps (RFC) and the Royal Naval Air Service (RNAS). Overseas, SABCA of Belgium produced a further 15 DH.4s during 1926.
As production progressed, various changes and improvements to the design were introduced upon the DH.4. As time went on, production DH.4s were fitted with Eagle engines of increasing power, settling on the 375 hp (280 kW) Eagle VIII, which powered the majority of frontline DH.4s by the end of 1917. However, this transition was greatly hindered as by January 1917, it had become clear that there was a chronic shortage of Rolls-Royce aero engines, and of the Eagle in particular; it has been claimed by Bruce that this shortfall was partially the result of protracted decision-making on the part of the Air Board.
In response to the limited availability of the Eagle, extensive investigations into the use of alternative engines for the DH.4 were conducted. This resulted in aircraft being outfitted with a diverse range of engines; these included the BHP (230 hp/170 kW), the Royal Aircraft Factory RAF3A (200 hp/150 kW), the Siddeley Puma (230 hp/170 kW) and the 260 hp (190 kW) Fiat, all of which were used to power, which encountered varying degrees of success, to production aircraft. None of these engines proved to be capable of matching the performance of the Eagle engine, which remained the preferred options despite the persistent supply constraints.
Upon the entry of the United States into the First World War on 6 April 1917, the aviation section of the U.S. Signal Corps was relatively unprepared for the task, not being equipped with any aircraft suitable for combat operations. However, considerable optimism and energy was put into addressing this identified need, leading to the mobilization of American industry to set about the production of contemporary combat aircraft. As there were no suitable aircraft domestically, a technical commission, known as the Bolling Commission, was dispatched to Europe to seek out the best available combat aircraft and to make arrangements to enable their production to be established in the United States.
As a result of the efforts of the Bolling Commission, the DH.4, along with the Bristol F.2 Fighter, the Royal Aircraft Factory S.E.5, and French SPAD S.XIII were selected. On 27 July 1917, a single DH.4 was sent to the United States as a pattern aircraft. It was not until 1918 that the first American-built DH.4s came off the production line. Several different manufacturers, including the Boeing Airplane Corporation, Dayton-Wright Airplane Company, the Fisher Body Corporation, and the Standard Aircraft Corporation produced this Americanized variant of the DH.4, featuring over 1,000 modifications from the original British design, to equip the American air services. A total of 9,500 DH.4s were ordered from American manufacturers, of which 1,885 actually reached France during the war. In American production, the new Liberty engine, which had proved suitable as a DH.4 power plant, was adopted. The Liberty would also eventually be adopted by the British, powering the DH.9A variant of the type.
After the war, a number of firms, most significant of these being Boeing, were contracted by the U.S. Army to remanufacture surplus DH.4s to the improved DH.4B standard. Internally referred to by Boeing as the Model 16, deliveries of 111 aircraft from this manufacturer took place between March and July 1920; reportedly, roughly 50 of these were returned for further refurbishments three years later.
During 1923, the Army placed an order for a new DH.4 variant from Boeing, distinguished by a fuselage of fabric-covered steel tube in place of the original plywood structure. These three prototypes were designated DH.4M-1 (M for modernized) and were ordered into production alongside the generally similar DH.4M-2 developed by Atlantic Aircraft. A total of 22 of the 163 DH.4M-1s were converted by the Army into dual-control trainers (DH.4M-1T) and a few more into target tugs (DH.4M-1K). Thirty of the aircraft ordered by the Army were diverted to the Navy for Marine Corps use, these designated O2B-1 for the base model, and O2B-2 for aircraft equipped for night and cross-country flying.
The Airco DH.4 was a conventional tractor two bay biplane of all-wooden construction. It was entirely built of traditional materials. The forward fuselage section and the underside of the tail area was covered by a 3mm plywood skin; this construction led to the fuselage being both strong and lightweight, heavily contributing to cross-bracing only being used for the four bays directly behind the rear cockpit. The nose of the aircraft was considerably longer than necessary, the cowling having been originally designed to accommodate the Beardmore Halford Pullinger (BHP) engine, rather than the Rolls-Royce Eagle that was adopted for production instead.
The DH.4 was powered by a variety of engines, including the Eagle, the BHP, the American Liberty, Royal Aircraft Factory RAF3A, the Siddeley Puma and the Fiat. Regardless of the engine used, it drove a four-bladed propeller mounted upon the nose. Cooling for the engine was provided via an oval-shaped radiator, while a port-mounted exhaust manifold discarded waste emissions above the upper wing. An unusual modification featuring on a small proportion of production DH.4s was the inversion of the engine, a design change that had been implemented in order to better accommodate the relatively-tall Ricardo-Halford-Armstrong (RHA) supercharged engine, which would otherwise unduly obstruct the pilot's forward field of view.
The DH.4 was operated by a crew of two, who were accommodated in widely spaced cockpits, between which the fuel tank was positioned. While the crew arrangement provided good fields of view for both the pilot and observer; however, it had the noticeable downside of causing communication problems between the two crew members, particularly during combat situation, where the speaking tube that linked the two cockpits was of only limited use. On the majority of American-built aircraft, the pilot's seating and fuel tank arrangement were switched around; aviation author Peter M Bowers credits this change with improving the pilot's safety in the event of a crash, as well as allowing for better communication with the observer.
The DH.4 was armed with a single forward-firing synchronised Vickers machine gun along with either one or two .303 in (7.7 mm) Lewis guns fitted on a Scarff ring fired by the observer. In terms of bomb load, it accommodate a maximum payload of 460 lb (210 kg), which could be mounted upon external racks. Throughout the type's production life, a number of alterations to the armaments, such as the ergonomics of the observer's Lewis gun and the installation of an additional Vickers gun, were implemented. A pair of DH.4s were outfitted with COW 37 mm guns for experimental purposes, but the war came to a close prior to firing trials being conducted. All armaments would typically by removed on those DH.4s that were used by civil operators, including ex-military aircraft that were sold on in great numbers following the end of the Great War.
One of the more elaborate modifications of the DH.4 was the adaption of the type as a seaplane. It was furnished with large floats, which were allegedly based upon the design of those used upon the German Hansa-Brandenburg W.29 seaplane. According to Bruce, while no such aircraft entered into operational service as a result of competition from other aircraft to perform the role, a number of DH.4 seaplanes were produced for trial purposes at Felixstowe and were successfully flown.
The DH.4 entered service with the RFC in January 1917, first being used by No. 55 Squadron. More squadrons were equipped with the type to increase the bombing capacity of the RFC, with two squadrons re-equipping in May, and a total of six squadrons by the end of the year. During late 1917, the uptake of the type by the RFC was accelerated due to a desire to launch retaliatory bombing raids upon Germany following such attacks having been conducted against the British mainland. While Russia had been an early customer for the DH.4, having ordered 50 of the type in September 1917, the Russian and British governments subsequently agreed to delay the former's deliveries, instead diverting those aircraft to RFC squadrons in France.
As well as the RFC, the RNAS also used the DH.4. During the spring of 1917, No. 2 Squadron became the first unit of the service to receive examples of the type. The RNAS flew their DH.4s over both France and over Italy, specifically the Aegean front in the latter case. The DH.4 was typically used to conduct coastal patrols by the RNAS. One such flight, crewed by the pilot Major Egbert Cadbury and Captain Robert Leckie (later Air Vice-Marshal) as gunner, shot down Zeppelin L70 on 5 August 1918. In another incident, a group of four RNAS DH.4s were jointly credited with the sinking of the German U-boat UB 12 on 19 August 1918.
The DH.4 proved a huge success and was often considered the best single-engined bomber of World War I.[N 1] Even when fully loaded with bombs, with its reliability and impressive performance, the type proved highly popular with its crews. The Airco DH.4 was easy to fly, and especially when fitted with the Rolls-Royce Eagle engine, its speed and altitude performance gave it a good deal of invulnerability to German fighter interception, so that the DH.4 often did not require a fighter escort on missions, a concept furthered by de Havilland in the later Mosquito of the Second World War.
A drawback of the design was the distance between pilot and observer, as they were separated by the large main fuel tank. This made communication between the crew members difficult, especially in combat with enemy fighters. There was also some controversy (especially in American service) that this placement of the fuel tank was inherently unsafe. In fact, most contemporary aircraft were prone to catching fire in the air.[N 2] The fire hazard was reduced, however, when the pressurised fuel system was replaced by one using wind-driven fuel pumps late in 1917, although this was not initially adopted by American-built aircraft. The otherwise inferior DH.9 brought the pilot and observer closer together by placing the fuel tank in the usual place, between the pilot and the engine.
Despite its success, numbers in service with the RFC actually started to decline from spring 1918, mainly due to a shortage of engines, and production switched to the DH.9, which turned out to be disappointing, being inferior to the DH.4 in most respects. It was left to the further developed DH.9A, with the American Liberty engine, to satisfactorily replace the DH.4.
When the Independent Air Force was set up in June 1918 to carry out strategic bombing of targets in Germany, the DH.4s of 55 Squadron formed part of it, being used for daylight attacks. 55 Squadron developed tactics of flying in wedge formations, bombing on the leader's command and with the massed defensive fire of the formation deterring attacks by enemy fighters. Despite heavy losses, 55 Squadron continued in operation, the only one of the day bombing squadrons in the Independent Force which did not have to temporarily stand down owing to aircrew losses.
After the Armistice, the RAF formed No. 2 Communication Squadron, equipped with DH.4s to carry important passengers to and from the Paris Peace Conference. Several of the DH.4s used for this purpose were modified with an enclosed cabin for two passengers at the request of Bonar Law. These aircraft were designated DH.4A, with at least seven being converted for the RAF, and a further nine for civil use.
At the time of its entry into the war, the United States Army Air Service lacked any aircraft suitable for front line combat. It therefore procured various aircraft from the British and French, one being the DH.4. As the DH-4, it was manufactured mostly by Dayton-Wright and Fisher Body for service with the United States from 1918, the first American built DH-4 being delivered to France in May 1918, with combat operations commencing in August 1918. The powerplant was a Liberty L-12 of 400 hp (300 kW) and it was fitted with two .30 in (7.62 mm) Marlin (a development of the Colt-Browning) machine guns in the nose and two .30 in (7.62 mm) Lewis guns in the rear and could carry 322 lb (146 kg) of bombs. it could also be equipped with various radios like the SCR-68 for artillery spotting missions. The heavier engine reduced performance compared with the Rolls-Royce powered version, but as the "Liberty Plane" it became the US Army Air Service standard general purpose two-seater, and on the whole was fairly popular with its crews.
Aircrew operating the DH-4 were awarded four of the six Medals of Honor awarded to American aviators. First Lieutenant Harold Ernest Goettler and Second Lieutenant Erwin R. Bleckley received posthumous awards after being killed on 12 October 1918 attempting to drop supplies to the Lost Battalion of the 77th Division, cut off by German troops during the Meuse-Argonne Offensive; while Second Lieutenant Ralph Talbot and Gunnery Sergeant Robert G. Robinson of the United States Marine Corps (USMC) were awarded the Medal of Honor for beating off attacks from 12 German fighters during a bombing raid over Belgium on 8 October 1918. The type flew with 13 U.S. squadrons by the end of 1918.
Following the end of the First World War, America had a large surplus of DH-4s, with the improved DH-4B becoming available, although none had been shipped to France. It was therefore decided that there was no point in returning aircraft across the Atlantic, so those remaining in France, together with other obsolete observation and trainer aircraft, were burned in what became known as the "Billion Dollar Bonfire". With limited funds available to develop and purchase replacements, the remaining DH-4s formed a major part of American air strength for several years, used for many roles, with as many as 60 variants produced. DH-4s were also widely used for experimental flying, being used as engine testbeds and fitted with new wings. They were used for the first trials of air-to-air refueling on 25 June 1923, and one carried out an endurance flight of 37 hours, 15 minutes on 27–28 August, being refueled 16 times and setting 16 new world records for distance, speed and duration. The DH-4 remained in service with the United States Army Air Corps, successor to the United States Army Air Service, until 1932.
A large number of DH-4s were also used by the United States Navy and United States Marine Corps, both during the First World War and postwar. The Navy and Marine Corps received a total of 51 DH-4s during wartime, followed by 172 DH-4B and DH-4B-1 aircraft postwar and 30 DH-4M-1s with welded steel-tube fuselages (redesignated O2B) in 1925. They remained in service with the Marine Corps until 1929, being used against rebel factions in Nicaragua in 1927, carrying out the first dive-bombing attacks made by U.S. military forces. The U.S. Navy converted some DH-4M-1s into primitive air ambulances that could carry one stretcher casualty in an enclosed area behind the pilot.
Following the end of the First World War, large numbers of DH.4s and DH.4As were used to operate scheduled passenger services in Europe by such airlines as Aircraft Transport and Travel, Handley Page Transport and the Belgium airline SNETA, G-EAJC of Aircraft Transport and Travel flying the first British commercial passenger service from Hounslow Heath Aerodrome to Paris Le Bourget on 25 August 1919, carrying a reporter from the Evening Standard newspaper and a load of newspapers and other freight. They were used by Aircraft Transport and Travel until it shut down in 1920, while Handley Page Transport and SNETA continued operating the DH.4 until 1921. One aircraft was used by Instone Air Lines until its merger into Imperial Airways in 1924.
The DH.4 were also used by the Australian airline QANTAS, flying its first airmail service in 1922. Twelve DH.4s forming part of the Imperial Gift to Canada were used for forestry patrol and survey work, spotting hundreds of forest fires and helping to save millions of dollars worth of timber, with the last example finally being withdrawn in 1927.
The U.S. Post Office also adopted the DH-4 to carry air mail. The Service acquired 100 of them from the army in 1918, and retrofitted them to make them safer, denominating them as the DH.4B. In 1919, the DH-4B was standardised by the US Post Office, being modified to be flown from the rear cockpit with a 400 lb (180 kg) watertight mail compartment replacing the forward cockpit. The airmail DH-4B were later modified with revised landing gear and an enlarged rudder. DH-4s were used to establish a coast-to-coast, transcontinental airmail service, between San Francisco and New York, a distance of 2,680 mi (4,310 km), involving night flight, the first services starting on 21 August 1924. The DH-4 continued in Post Office service until 1927, when the last airmail routes were passed to private contractors.
Media related to Airco DH.4 at Wikimedia Commons4M
4M or 4-M may refer to:
4m, or 4 metres
4-meter band in amateur radio
4M, a model of Toyota M engine
4M, a model of Mitsubishi 4M4 engine
4M, a model of HP LaserJet 4
DC-4M, a designation of Canadair North Star
A-4M, a model of Douglas A-4 Skyhawk
Fokker DH-4M, see Airco DH.4
VF-4M, see VMA-211
VB-4M, see VMFA-232
PB-4M, see Osa (handgun)
Sun-4m, a model of Sun-4 workstation
Mayall 4m telescope, see Nicholas U. Mayall Telescope
Meade 4M Community, an astronomy awareness community sponsored by Meade Instruments
LAN Argentina, an airline based in Buenos Aires, Argentina
J-4M, see Barnett J4B
4M of manufacture industries are Man, Money, Material and Machine. Also see resource management and Ishikawa diagram.
4M Software applications for Engineers, see IDEA Architectural and FINE MEP
4M, Manfred Memorial Moon Mission, first commercial moon mission
4M, the production code for the 1976 Doctor Who serial The Masque of MandragoraArthur Thomas Drinkwater
Captain Arthur Thomas Drinkwater (3 February 1894 – 1972), was an Australian-born First World War flying ace. He was credited with nine aerial victories; six of these were scored when Drinkwater was a bomber pilot, making him one of the rare bomber pilot aces.Beardmore Halford Pullinger
Beardmore-Halford-Pullinger (BHP) were aircraft engines used in production between 1916 and 1918. The engines were used on many notable First World War aircraft, such as the Airco DH.4, DH.9, DH.10, de Havilland DH.15 and Avro 529 aircraft.
The engines were used as the basis for later designs such as the Siddeley Puma and A.D.C Nimbus (1926).Boeing Model 42
The Boeing Model 42 (also Boeing XCO-7 for Experimental Corps Observation Model 7) was an American biplane aircraft developed from the Airco DH.4, taking advantage of the large number of aircraft left over after the end of World War I.Bréguet 11 Corsaire
The Bréguet XI was a prototype French biplane bomber of the First World War.Charles Bartlett (RAF officer)
Major Charles Philip Oldfield Bartlett (3 January 1889 – 1987) was an English First World War flying ace credited with eight aerial victories in the course of flying bombing sorties against the Germans.
He remained in service after the war, even though he struggled with health issues that threatened his forced resignation. He would serve until 1932, rising to the rank of Squadron Leader.Claud Stokes
Captain Claud Harry Stokes (16 March 1884 – 7 November 1918) was a British First World War flying ace credited with five aerial victories, all while flying the Airco DH.4.DH4
DH4 may refer to:
Airco DH.4, British World War I two-seat biplane
de Lackner HZ-1 Aerocycle, also known as the YHO-2 and DH-4 Heli-Vector (1950s)
Bombardier Dash 8 Q400, turboprop passenger airliner (since 1996, called DH4 by various airlines)De Havilland DH.14 Okapi
The de Havilland DH.14 Okapi was a British two-seat day bomber of the 1910s built by de Havilland. The aircraft was designed as an Airco DH.4 and DH.9 replacement, but it never entered production.E. Grahame Joy
Major Ernst Grahame Joy (2 November 1888 – 21 June 1993) was an American-born Canadian who became a flying ace during the First World War, credited with eight aerial victories. He had set aside his law studies and family obligations to join the Canadian Expeditionary Force, then transferred to the Royal Flying Corps. While he left military service after World War I to practice law, he would return to the colours for World War II.Eric Betts
Air Vice Marshal Eric Bourne Coulter Betts, (24 January 1897 – 30 October 1971) was an Irish air officer of the British Royal Air Force. He began his career in the Royal Naval Air Service during the First World War. He became a flying ace credited with six aerial victories, although acedom was incidental to his more important mission of long range photographic reconnaissance, for which he was decorated.He remained in military service post-war, rising through the ranks of the Royal Air Force to group captain just before the Second World War began. As that war started, he was an influential participant in the United Kingdom's effort to gear up for the conflict; his sixteen early forecasts of needed personnel and logistic requirements for the Royal Air Force were accurate within a five percent margin.Later in the war, having been promoted to air vice marshal, he was in charge of administration for Middle East Command. He retired in that rank post-war, on 10 March 1946.George Darvill
Captain George William Francis Darvill (26 October 1898 – September 1950) was an English World War I flying ace credited with nine aerial victories.George Kenney
George Churchill Kenney (6 August 1889 – 9 August 1977) was a United States Army Air Forces general during World War II. He is best known as the commander of the Allied Air Forces in the Southwest Pacific Area (SWPA), a position he held between August 1942 and 1945.
Kenney enlisted as a flying cadet in the Aviation Section, U.S. Signal Corps in 1917, and served on the Western Front with the 91st Aero Squadron. He was awarded a Silver Star and the Distinguished Service Cross for actions in which he fought off German fighters and shot two down. After hostilities ended he participated in the Occupation of the Rhineland. Returning to the United States, he flew reconnaissance missions along the border between the US and Mexico during the Mexican Revolution. Commissioned into the Regular Army in 1920, he attended the Air Corps Tactical School, and later became an instructor there. He was responsible for the acceptance of Martin NBS-1 bombers built by Curtis, and test flew them. He also developed techniques for mounting .30 caliber machine guns on the wings of an Airco DH.4 aircraft.
In early 1940, Kenney became Assistant Military Attaché for Air in France. As a result of his observations of German and Allied air operations during the early stages of World War II, he recommended significant changes to Air Corps equipment and tactics. In July 1942, he assumed command of the Allied Air Forces and Fifth Air Force in General Douglas MacArthur's Southwest Pacific Area. Under Kenney's command, the Allied Air Forces developed innovative command structures, weapons, and tactics that reflected Kenney's orientation towards attack aviation. The new weapons and tactics won perhaps his greatest victory, the Battle of the Bismarck Sea, in March 1943. In June 1944 he was appointed commander of the Far East Air Forces (FEAF), which came to include the Fifth, Thirteenth, and Seventh Air Forces.
In April 1946, Kenney became the first commander of the newly formed Strategic Air Command (SAC), but his performance in the role was criticized, and he was shifted to become commander of the Air University, a position he held from October 1948 until his retirement from the Air Force in September 1951.Liberty L-12
The Liberty L-12 was an American 27-litre (1,649 cubic inch) water-cooled 45° V-12 aircraft engine of 400 hp (300 kW) designed for a high power-to-weight ratio and ease of mass production. It was succeeded by the Packard 1A-2500.List of victories of Rudolf Berthold
Rudolf Berthold had a reputation as a ruthless, fearless and—above all—very patriotic combatant. His perseverance, bravery, and willingness to return to combat while still wounded made him one of the most famous German pilots of World War I. Between 1916 and 1918, he shot down 44 enemy planes—16 of them while flying one-handed. His feats would earn him both the Blue Max and a sordid end.No. 125 Squadron RAF
Number 125 (Newfoundland) Squadron was a Royal Air Force squadron active during World War II and briefly in the mid-1950s. Throughout its service the squadron primarily operated night fighters.No. 223 Squadron RAF
No. 223 Squadron RAF was a squadron of the Royal Air Force. Originally formed as part of the Royal Naval Air Service (RNAS), the Squadron flew in both World Wars.Walter Naylor
Air Mechanic First Class (originally, Gunlayer) Walter Naylor was the leading observer ace of the Royal Naval Air Service, with 14 accredited victories. He flew as an enlisted observer/gunner in Airco DH.4 bombers in 5 Naval Squadron along the English Channel.William Edward Green
Lieutenant Colonel William Edward Green (20 October 1898–23 May 1940) began his military career as a World War I flying ace. He was credited with nine aerial victories while flying the Airco DH.4, making him one of the few World War I aces who were bomber pilots.
After World War I, he transferred from the Royal Air Force to the Territorial Army, serving until his death in action on 23 May 1940.
Boeing aircraft model numbers
USAAS observation aircraft
USN observation aircraft designations, pre-1962