# Airco DH.4

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British bomber used during the First World War

"DH-4" redirects here. For the 1950s flying platform, see [de Lackner HZ-1 Aerocycle](/source/De_Lackner_HZ-1_Aerocycle).

Airco DH.4 A Canadian DH.4 registered G-CYDK parked. General information Type Light bomber / General purpose Manufacturer Airco Built by Boeing Airplane Corporation Dayton-Wright Company Fisher Body Standard Aircraft Corporation Status Retired 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.[1][2] History Introduction date March 1917 First flight August 1916 Retired 1932 (United States Army Air Service) Developed into Airco DH.9 Airco DH.9A Dayton-Wright Cabin Cruiser

The **Airco DH.4** is a British two-seat [biplane](/source/Biplane) [day bomber](/source/Day_bomber) of the [First World War](/source/World_War_I). It was designed by [Geoffrey de Havilland](/source/Geoffrey_de_Havilland) (hence "DH") for [Airco](/source/Airco), and was the first British two-seat light day-bomber capable of defending itself.

It was [designed and developed specifically as a bomber](/source/Bomber#The_first_bombers), as well as [aerial reconnaissance](/source/Aerial_reconnaissance) missions. The DH.4 was to have been powered by the new 160 hp (119 kW) [Beardmore Halford Pullinger](/source/Beardmore_Halford_Pullinger) (BHP) engine, but problems with that resulted in numerous other engines being used, perhaps the best of which was the 375 hp (280 kW) [Rolls-Royce Eagle](/source/Rolls-Royce_Eagle) engine. The DH.4 first flew in August 1916 and it entered operational service in France on 6 March 1917 less than a year later. The majority were manufactured as general purpose two-seaters in the [United States](/source/United_States) for the American expeditionary forces in France, becoming the only American made plane to see combat in World War I.

Following the [Armistice of 11 November 1918](/source/Armistice_of_11_November_1918), many DH.4s were sold to civil operators where it was found to be particularly useful as a [mailplane](/source/Mailplane). Early commercial passenger airplane service in Europe was initiated with modified variants of the DH-4. War-surplus DH-4s became key aircraft in newly emerging air forces throughout the world. The U.S. Army later had several companies re-manufacture its remaining DH.4s to DH.4B standard and they operated the type into the early 1930s.

## Development

### Origins

The DH.4 was designed by Geoffrey de Havilland as a light two-seat combat aircraft, and was intended to perform both [day bomber](/source/Bomber#The_first_bombers) and [aerial reconnaissance](/source/Aerial_reconnaissance) missions.[3] The intention was for it to be powered by the newly developed 160 hp (120 kW) [Beardmore Halford Pullinger](/source/Beardmore_Halford_Pullinger) (BHP) engine. The DH.4 was developed in parallel to the rival [Bristol Fighter](/source/Bristol_F.2_Fighter).[3] During August 1916, the prototype DH.4 made its first flight, powered by a prototype 230 hp (172 kW) BHP engine.[4]

Initial flight tests revealed it to have favourable handling and performance.[5] The [Central Flying School](/source/Central_Flying_School) (CFS) conducted early evaluation flights using the prototype, leading to it producing a favourable report on the aircraft, observing good 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 which were unmatched by any of its predecessors.[5] While flying trials with the prototype had been producing promising results, it soon became clear that the BHP engine would require a major redesign prior to entering production.[5]

Even by the time of flying trials with the first prototype, there had been no finalised plans for quantity production of the BHP engine.[5] Coincidentally, another suitable and promising aeroengine, the water-cooled [Rolls-Royce Eagle](/source/Rolls-Royce_Eagle) in-line engine, was approaching the end of its development process.[3] According to Bruce, the Eagle shared the same basic configuration as the BHP engine, which greatly aided in its adoption by de Havilland, as did the engine's endorsement by [William Beardmore](/source/William_Beardmore%2C_1st_Baron_Invernairn). During the summer of 1916, a second prototype, equipped with the Rolls-Royce engine, conducted its first flight.[5]

In response to its favourable performance, the [Royal Flying Corps](/source/Royal_Flying_Corps) (RFC) decided to place an initial order for the type during late 1916.[6] Separately to the RFC's interactions with the DH.4, it had received substantial interest from the [Royal Navy](/source/Royal_Navy) as well.[7] The [Admiralty](/source/British_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](/source/Royal_Naval_Air_Service).[7]

### Production

An early production DH.4

During late 1916, the first order for 50 DH.4s, powered by 250 hp (190 kW) Eagle III engines, was received from the RFC.[8] 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.[6] 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](/source/Vickers_machine_gun) for the pilot, while the observer was provided with a 0.303 in (7.7 mm) [Lewis gun](/source/Lewis_gun) mounted on a [Scarff ring](/source/Scarff_ring).[9]

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 Works](/source/Westland_Aircraft).[10] 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](/source/Royal_Flying_Corps) (RFC) and the [Royal Naval Air Service](/source/Royal_Naval_Air_Service) (RNAS).[11] Overseas, [SABCA](/source/SABCA) of [Belgium](/source/Belgium) produced a further 15 DH.4s during 1926.[12][10]

As production progressed, various changes and improvements to the design were introduced upon the DH.4.[7] As time went on, production DH.4s were fitted with Eagle engines of increasing power, ending with 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.[7]

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](/source/Royal_Aircraft_Establishment) [RAF3A](/source/RAF_3) (200 hp (150 kW)), the [Siddeley Puma](/source/Siddeley_Puma) (230 hp (170 kW)) and the 260 hp (190 kW) [Fiat](/source/Fiat), all of which were used to power production aircraft, with varying degrees of success.[8] 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.[13]

### American versions

American DH.4 planes being assembled in France during World War One

At the time of entry of the [United States](/source/United_States) into the First World War on 6 April 1917, the aviation section of the [U.S. Signal Corps](/source/Aviation_Section%2C_U.S._Signal_Corps) was unprepared, not being equipped with any aircraft suitable for combat.[14] 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.[14] As a result of the efforts of the Bolling Commission, the DH.4, along with the [Bristol F.2 Fighter](/source/Bristol_F.2_Fighter), the [Royal Aircraft Factory S.E.5](/source/Royal_Aircraft_Factory_S.E.5), and French [SPAD S.XIII](/source/SPAD_S.XIII) were selected.[14] 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.[15] Several different manufacturers, including the [Boeing Airplane Corporation](/source/Boeing), [Dayton-Wright Company](/source/Dayton-Wright_Company), the [Fisher Body Corporation](/source/Fisher_Body), and the [Standard Aircraft Corporation](/source/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.[16] 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](/source/Liberty_L-12), which had proved suitable as a DH.4 power plant, was adopted. The Liberty was also eventually adopted by the British to power the [DH.9A](/source/Airco_DH.9A) variant of the type.[1][17]

After the war, a number of firms, most significant of these being [Boeing](/source/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.[18][19]

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.[20] 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](/source/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](/source/Cross-country_flying).[21]

## Design

Strength tests on various DH-4 wing ribs during World War I

The Airco DH.4 was a conventional tractor [two bay](/source/Interplane_strut) biplane of all-wooden construction.[3] It was entirely built of traditional materials. The forward fuselage section and the underside of the tail area was covered by a 3mm [plywood](/source/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.[3] The nose of the aircraft was considerably longer than necessary, the cowling having been originally designed to accommodate the [Beardmore Halford Pullinger](/source/Beardmore_Halford_Pullinger) (BHP) engine, rather than the [Rolls-Royce Eagle](/source/Rolls-Royce_Eagle) that was adopted for production instead.[3]

The DH.4 was powered by a variety of engines, including the Eagle, the BHP, the American [Liberty](/source/Liberty_L-12), [Royal Aircraft Factory](/source/Royal_Aircraft_Establishment) [RAF3A](/source/RAF_3), the [Siddeley Puma](/source/Siddeley_Puma) and the [Fiat](/source/Fiat).[3] Regardless of the engine used, it drove a four-bladed [propeller](/source/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.[3] 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](/source/Supercharger) engine, which would otherwise unduly obstruct the pilot's forward field of view.[13]

The DH.4 was operated by a crew of two, who were accommodated in widely spaced cockpits, between which the fuel tank was positioned.[8] 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 situations, where the [speaking tube](/source/Speaking_tube) that linked the two cockpits was of only limited use.[22][6] 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.[23]

The DH.4 was armed with a single forward-firing synchronised [Vickers machine gun](/source/Vickers_machine_gun) along with either one or two .303 in (7.7 mm) [Lewis guns](/source/Lewis_gun) fitted on a [Scarff ring](/source/Scarff_ring) fired by the observer. It could carry 460 lb (210 kg) of bombs, which could be mounted upon external racks.[22] There were several alterations to the aircraft's armament throughout its production life, such as improvement in the [ergonomics](/source/Ergonomics) of the observer's Lewis gun and the installation of an additional Vickers gun.[13] A pair of DH.4s were outfitted with [COW 37 mm guns](/source/COW_37_mm_gun) for experimental purposes, but the war came to a close prior to firing trials being conducted.[10] All armaments would typically be removed from 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 adaptation of the type as a seaplane.[10] It was furnished with large [floats](/source/Float_(nautical)), which were allegedly based upon the design of those used upon the German [Hansa-Brandenburg W.29](/source/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](/source/Felixstowe) and were successfully flown.[10]

## Operational history

### British military service

The DH.4 entered service with the RFC in January 1917, first being used by [No. 55 Squadron](/source/No._55_Squadron_RAF).[8] 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.[8][24] 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](/source/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.[25]

As well as the RFC, the RNAS also used the DH.4. During the spring of 1917, [No. 2 Squadron](/source/No._2_Squadron_RAF) became the first unit of the service to receive examples of the type.[24] The RNAS flew their DH.4s over both [France](/source/France) and over [Italy](/source/Italy), specifically the [Aegean](/source/Aegean_Sea) front in the latter case.[8] The DH.4 was typically used to conduct coastal patrols by the RNAS. One such flight, crewed by the pilot [Major](/source/Major_(rank)) [Egbert Cadbury](/source/Egbert_Cadbury) and [Captain](/source/Captain_(land)) [Robert Leckie](/source/Robert_Leckie_(aviator)) (later Air Vice-Marshal) as gunner, shot down [Zeppelin](/source/Zeppelin) *L70* on 5 August 1918.[26] In another incident, a group of four RNAS DH.4s were jointly credited with the sinking of the German [U-boat](/source/U-boat) [*UB 12*](https://en.wikipedia.org/w/index.php?title=SM_UB_12&action=edit&redlink=1) on 19 August 1918.[26][27]

The DH.4 proved a huge success and was often considered the best single-engined bomber of World War I.[Note 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,[28] so that the DH.4 often did not require a fighter escort on missions, a concept furthered by [de Havilland](/source/De_Havilland) in the later [Mosquito](/source/De_Havilland_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.[29] There was also some controversy (especially in American service) that this placement of the fuel tank was inherently unsafe.[30][31] In fact, most contemporary aircraft were prone to catching fire in the air.[Note 2] The fire hazard was reduced, however, when the pressurised fuel system was replaced by one using wind-driven fuel pumps late in 1917,[29] although this was not initially adopted by American-built aircraft.[33] The otherwise inferior [DH.9](/source/Airco_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](/source/Airco_DH.9A), with the American Liberty engine, to satisfactorily replace the DH.4.

When the [Independent Air Force](/source/Independent_Air_Force) was set up in June 1918 to carry out [strategic bombing](/source/Strategic_bombing) of targets in [Germany](/source/Germany), the DH.4s of 55 Squadron formed part of it, being used for daylight attacks.[22] 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.[34] 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.[35]

After the [Armistice](/source/Armistice_with_Germany_(Compi%C3%A8gne)), the RAF formed [No. 2 Communication Squadron](https://en.wikipedia.org/w/index.php?title=No._2_Communication_Squadron_RAF&action=edit&redlink=1), equipped with DH.4s to carry important passengers to and from the [Paris Peace Conference](/source/Paris_Peace_Conference%2C_1919). Several of the DH.4s used for this purpose were modified with an enclosed cabin for two passengers at the request of [Bonar Law](/source/Bonar_Law).[36] One of these planes was extensively used by Prime Minister [David Lloyd George](/source/David_Lloyd_George) and was sometimes called *Lloyd George's airplane* - probably the first aeroplane widely used by a political leader.[37][38] Modified aircraft were designated DH.4A, with at least seven being converted for the RAF, and a further nine for civil use.[39]

### United States military service

At the time of its entry into the war, the [United States Army Air Service](/source/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.[40][41] The powerplant was a 400 hp (300 kW) [Liberty L-12](/source/Liberty_L-12) and it was fitted with two forward-firing .30 in (7.62 mm) [synchronized](/source/Synchronization_gear) [Marlin-Rockwell M1917](/source/M1895_Colt%E2%80%93Browning_machine_gun#Marlin_Rockwell_M1917/M1918_versions) (a development of the [Colt-Browning](/source/M1895_Colt%E2%80%93Browning_machine_gun)) machine guns in the nose and two .30 in (7.62 mm) [Lewis guns](/source/Lewis_gun) in the rear and could carry 322 lb (146 kg) of bombs. it could also be equipped with various radios like the [SCR-68](/source/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.

A formation of DH-4s in flight

Aircrew operating the DH-4 were awarded four of the six [Medals of Honor](/source/Medal_of_Honor) awarded to American aviators. [First Lieutenant](/source/First_Lieutenant#U.S._Army,_U.S._Marine_Corps_and_U.S._Air_Force) [Harold Ernest Goettler](/source/Harold_Ernest_Goettler) and [Second Lieutenant](/source/Second_Lieutenant) [Erwin R. Bleckley](/source/Erwin_R._Bleckley) received posthumous awards after being killed on 12 October 1918 attempting to drop supplies to the [Lost Battalion](/source/Lost_Battalion_(World_War_I)) of the [77th Division](/source/77th_Infantry_Division_(United_States)), cut off by German troops during the [Meuse-Argonne Offensive](/source/Meuse-Argonne_Offensive);[40] while Second Lieutenant [Ralph Talbot](/source/Ralph_Talbot) and [Gunnery Sergeant](/source/Gunnery_Sergeant) [Robert G. Robinson](/source/Robert_G._Robinson) of the [United States Marine Corps](/source/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.[42][43][*[better source needed](https://en.wikipedia.org/wiki/Wikipedia:Verifiability#Questionable_sources)*] The type flew with 13 U.S. squadrons by the end of 1918.[44]

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".[45][41] 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.[46] 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](/source/Aerial_refueling) on 27 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.[47] The DH-4 remained in service with the [United States Army Air Corps](/source/United_States_Army_Air_Corps), successor to the United States Army Air Service, until 1932.[48]

A large number of DH-4s were also used by the [United States Navy](/source/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.[49] They remained in service with the Marine Corps until 1929, being used against rebel factions in [Nicaragua](/source/United_States_occupation_of_Nicaragua) in 1927, carrying out the first dive-bombing attacks made by U.S. military forces.[49] 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.[50]

### Civil use

Robertson Aircraft Corp. operated DH-4 mailplane (CAM 2) 1926 at the [Historic Aircraft Restoration Museum](/source/Historic_Aircraft_Restoration_Museum)

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](/source/Aircraft_Transport_and_Travel), [Handley Page Transport](/source/Handley_Page_Transport) and the Belgium airline [SNETA](/source/SNETA). *G-EAJC* of Aircraft Transport and Travel flew the first British commercial passenger service from [Hounslow Heath Aerodrome](/source/Hounslow_Heath_Aerodrome) to [Paris Le Bourget](/source/Paris%E2%80%93Le_Bourget_Airport) on 25 August 1919, carrying a reporter from the *[Evening Standard](/source/London_Evening_Standard)* newspaper and a load of newspapers and other freight.[51][52] 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](/source/Instone_Air_Line) until its merger into [Imperial Airways](/source/Imperial_Airways) in 1924.[53]

In 1923 the U.S. Post Office released a stamp featuring the DeHavilland Biplane being used for airmail service[54]

On September 4, 1922, [Jimmy Doolittle](/source/Jimmy_Doolittle) made the first cross-country flight, flying a de Havilland DH-4 – which was equipped with early navigational instruments – from Pablo Beach (now [Jacksonville Beach](/source/Jacksonville_Beach)), Florida, to [Rockwell Field](/source/Rockwell_Field), San Diego, California, in 21 hours and 19 minutes, making only one refueling stop at [Kelly Field](/source/Kelly_Field).

The DH.4 were also used by the [Australian](/source/Australia) airline [QANTAS](/source/Qantas), flying its first [airmail](/source/Airmail) service in 1922.[55] Twelve DH.4s forming part of the [Imperial Gift](/source/Imperial_Gift) to [Canada](/source/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.[56][10]

The [U.S. Post Office](/source/United_States_Postal_Service) also adopted the DH-4 to carry air mail.[57][58] The Service acquired 100 of them from the army in 1918, and retrofitted them to make them safer, denominating them as the DH.4B.[57] 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](/source/Rudder).[59] 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.[60]

War-surplus DH-4s were available cheaply in sufficient quantities to stimulate the development of "utility aviation": surveying, commercial photography, law enforcement, agricultural applications and other practical applications.[61]

## Variants

DH-4 soaring above the clouds in France

Wright Radial Engine (R-1) fitted to a De Havilland DH-4B airframe

### UK variants

- **DH.4** : Two-seat day bomber biplane.

- **DH.4A** : Transport version. Built in the United Kingdom. Two passengers in glazed cabin behind pilot.

- **DH.4R** : Single seat racer – 450 hp (340 kW) [Napier Lion](/source/Napier_Lion) engine.

### Soviet variants

- copy of DH.4 manufactured by [Polikarpov](/source/Polikarpov) in the former [Dux Factory](/source/Dux_Factory) in the 1920s

### United States variants

[62]

- **DH-4** : Two-seat day bomber biplane, built in the United States.

- **DH-4A** : Civil version, built in the United States.

- **DH-4B** : Rebuilt version of Liberty powered DH-4 for [U.S. Air Service](/source/United_States_Army_Air_Service). Pilot's cockpit relocated to behind fuel tank, adjacent to observer's cockpit. - - **DH-4B-1** : Increased fuel capacity (110 US gal (420 L; 92 imp gal)). - **DH-4B-2** : Trainer version. - **DH-4B-3** : Fitted with 135 US gal (510 L; 112 imp gal) fuel tank - **DH-4B-4** : Civil version - **DH-4B-5** : Experimental civil conversion with enclosed cabin. - **DH-4BD** :Cropdusting version of DH-4B - **DH-4BG** : Fitted with smokescreen generators - **DH-4BK** : Night flying version - **DH-4BM**: Single seat version for communications - **DH-4BM-1** : Dual control version of BM - **DH-4BM-2** : Dual control version of BM - **DH-4-BP** : Experimental photo reconnaissance version - **DH-4-BP-1** : BP converted for survey work - **DH-4BS** : Testbed for supercharged Liberty - **DH-4BT** : Dual control trainer - **DH-4BW** : Testbed for Wright H engine

- **DH-4C** : 300 hp (220 kW) Packard engine

- **DH-4L** : Civil version

- **DH-4M** : Rebuilt version of DH-4 with steel tube fuselage.

- **DH-4Amb** : Ambulance.

- **DH-4M-1** – postwar version by Boeing (Model 16) with new fuselage, designated **O2B-1** by Navy - **DH-4M-1T** – Dual control trainer conversion of DH-4M - **DH-4M-1K** – target tug conversion - **O2B-2** – cross-country and night flying conversion for Navy

- **DH-4M-2** – postwar version by Atlantic

- **L.W.F. J-2** – Twin-engine long range development of DH-4 (also known as **Twin DH**), powered by two 200 hp (150 kW) [Hall-Scott](/source/Hall-Scott)-[Liberty L-6](/source/Liberty_L-6) engines and with wingspan of 52 ft 6 in (16.00 m); 20 built for U.S. Post Office, 10 for U.S. Army.[63][64]

**[XCO-7](/source/Boeing_Model_42)**
- (Boeing Model 42) Two-seat observation version with Boeing designed wings, enlarged tailplane and divided landing gear.

**XCO-8**
- Was a designation of one Atlantic DH.4M-2 fitted with Loening COA-1 wings and powered by a Liberty 12A engine.

## Operators

### Civil operators

**[Argentina](/source/Argentina)**

- [The River Plate Aviation Co. Ltd.](https://en.wikipedia.org/w/index.php?title=The_River_Plate_Aviation_Co._Ltd.&action=edit&redlink=1)

**[Australia](/source/Australia)**

- [QANTAS](/source/Qantas)

**[Belgium](/source/Belgium)**

- [SNETA](/source/SNETA)

**[United Kingdom](/source/United_Kingdom)**

- [Aircraft Transport and Travel Limited](/source/Aircraft_Transport_and_Travel)

- [Handley Page Transport](/source/Handley_Page_Transport)

- [Imperial Airways](/source/Imperial_Airways)

- [Instone Air Line](/source/Instone_Air_Line)

**[United States](/source/United_States)**

- [U.S. Post Office](/source/United_States_Postal_Service)

### Military operators

**[Belgium](/source/Belgium)**

- [Aviation Militaire Belge](/source/Belgian_Air_Force)

**[Canada](/source/Canada)**

- [Canadian Air Force (1918–1920)](/source/Canadian_Air_Force_(1918%E2%80%931920))

- [Royal Canadian Air Force](/source/Royal_Canadian_Air_Force)

**[Chile](/source/Chile)**

- [Chilean Air Force](/source/Chilean_Air_Force)

**[Cuba](/source/Cuba)**

- [Cuban Air Force](/source/Cuban_Air_Force) – American built DH-4s

**[Greece](/source/Greece)**

- [Hellenic Air Force](/source/Hellenic_Air_Force)

- [Hellenic Navy](/source/Hellenic_Navy)

**[Iran](/source/Iran)**

- [Imperial Iranian Air Force](/source/Imperial_Iranian_Air_Force)

**[Mexico](/source/Mexico)**

- [Fuerza Aérea Mexicana](/source/Mexican_Air_Force)

**[Nicaragua](/source/Nicaragua)**

- [Nicaraguan Air Force](/source/Nicaraguan_Air_Force) – The Nicaragua Air Force received seven DH-4Bs.[65]

**[New Zealand](/source/New_Zealand)**

- The [New Zealand Permanent Air Force](/source/New_Zealand_Permanent_Air_Force) operated two aircraft from 1919 to 1929. It was used by the NZPAF as an advanced training aircraft. The DH.4 has the distinction of being the first aircraft to fly over [Mount Cook](/source/Aoraki_%2F_Mount_Cook) on 8 September 1920. It also set a New Zealand altitude record of 21,000 ft (6,400 m) on 27 November 1919.

**[South Africa](/source/South_Africa)**

- [South African Air Force](/source/South_African_Air_Force)

**[Soviet Union](/source/Soviet_Union)**

- [Soviet Air Force](/source/Soviet_Air_Force)

**[Kingdom of Spain](/source/Kingdom_of_Spain)**

- [Spanish Air Force](/source/Spanish_Air_Force)

**[Turkey](/source/Turkey)**

- [Turkish Air Force](/source/Turkish_Air_Force)

**[United Kingdom](/source/United_Kingdom)**

- [Royal Flying Corps](/source/Royal_Flying_Corps)

- [Royal Air Force](/source/Royal_Air_Force)

- [Royal Naval Air Service](/source/Royal_Naval_Air_Service)

**[United States](/source/United_States)**

- [United States Army Air Service](/source/United_States_Army_Air_Service) - [8th Aero Squadron](/source/8th_Aero_Squadron) - [11th Aero Squadron](/source/11th_Aero_Squadron) - [20th Aero Squadron](/source/20th_Aero_Squadron) - [50th Aero Squadron](/source/50th_Aero_Squadron) - [85th Aero Squadron](/source/85th_Aero_Squadron) - [91st Aero Squadron](/source/91st_Aero_Squadron) - [104th Aero Squadron](/source/104th_Aero_Squadron) - [135th Aero Squadron](/source/135th_Aero_Squadron) - [163rd Aero Squadron](https://en.wikipedia.org/w/index.php?title=163rd_Aero_Squadron&action=edit&redlink=1) - [166th Aero Squadron](/source/166th_Aero_Squadron) - [168th Aero Squadron](/source/168th_Aero_Squadron) - [278th Aero Squadron](/source/278th_Aero_Squadron) - [354th Aero Squadron](/source/354th_Aero_Squadron)

- [United States Navy](/source/United_States_Navy)

- [United States Marine Corps](/source/United_States_Marine_Corps)

## Surviving aircraft

DH-4:

The DH-4B on display at the [National Museum of the United States Air Force](/source/National_Museum_of_the_United_States_Air_Force)

- 21959[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*] – The prototype American-built DH-4 is on display at the [National Air and Space Museum](/source/National_Air_and_Space_Museum) in [Washington D.C.](/source/Washington_D.C.)[66]

- Unknown ID – A DH-4 is on display at the [National Museum of the Marine Corps](/source/National_Museum_of_the_Marine_Corps) in [Triangle, Virginia](/source/Triangle%2C_Virginia).[67] It was restored by Century Aviation.[68]

- 32517 - A DH-4 is currently being reconstructed so it can be permanently displayed at a public venue in [Wichita, Kansas](/source/Wichita%2C_Kansas). It will commemorate [United States Army](/source/United_States_Army) [aviator](/source/Aviator) [Erwin R. Bleckley](/source/Erwin_R._Bleckley), who was [killed in action](/source/Killed_in_action) during [World War I](/source/World_War_I) while flying a DH-4 near the ["lost battalion"](/source/Lost_Battalion_(World_War_I)) in France.[69]

- Unknown ID – A DH-4 is on display at the Omaka Aviation Heritage Centre in [Blenheim, New Zealand](/source/Blenheim%2C_New_Zealand).[70] This aircraft was previously on display at the [Crawford Auto-Aviation Museum](/source/Crawford_Auto-Aviation_Museum) in [Cleveland, Ohio](/source/Cleveland%2C_Ohio) and was at one point loaned to the United States Air Force Museum.[71]

- Replica – A DH.4 is airworthy with The Vintage Aviator Limited in [Masterton, New Zealand](/source/Masterton%2C_New_Zealand). It was built by Century Aviation and is powered by a rebuilt Liberty V-12.[72]

- Replica – A DH-4 is on display at the [Museo del Aire](/source/Museo_del_Aire_(Madrid)) in [Madrid, Spain](/source/Madrid%2C_Spain).[73][74]

DH-4B:

Friends of Jenny DH.4, 2018

- Unknown ID – A DH-4B is on display in the main atrium of the [National Postal Museum](/source/National_Postal_Museum) in [Washington, D.C.](/source/Washington%2C_D.C.)[75]

- Unknown ID – A DH-4B at the [Pearson Air Museum](/source/Pearson_Air_Museum) in [Vancouver, Washington](/source/Vancouver%2C_Washington). It was restored by Century Aviation.[76][77][78]

- Unknown ID – A DH-4B is on display at the [National Museum of the United States Air Force](/source/National_Museum_of_the_United_States_Air_Force) in [Dayton, Ohio](/source/Dayton%2C_Ohio).[79] It was restored by Century Aviation.[80]

- Unknown ID – A DH-4B is on display at [Fantasy of Flight](/source/Fantasy_of_Flight) in [Polk City, Florida](/source/Polk_City%2C_Florida). It was restored by Century Aviation.[81]

- Unknown ID – A DH-4B is under restoration by Century Aviation for Fantasy of Flight in Polk City, Florida. It will be powered by a rebuilt Liberty V-12.[82]

DH-4M-1

- Unknown ID – A DH-4M-1 is on display at the [Evergreen Aviation and Space Museum](/source/Evergreen_Aviation_and_Space_Museum) in [McMinnville, Oregon](/source/McMinnville%2C_Oregon).[83] This aircraft was previously owned by [Paul Mantz](/source/Paul_Mantz).[84]

DH-4M-2A

- Unknown ID – A DH-4M-2A is airworthy at the [Historic Aircraft Restoration Museum](/source/Historic_Aircraft_Restoration_Museum) in [Maryland Heights, Missouri](/source/Maryland_Heights%2C_Missouri).[85][86][87][88]

## Specifications (DH.4 – Eagle VIII engine)

*Data from* *The British Bomber since 1914*,[8] *The de Havilland DH.4*[89]

**General characteristics**

- **Crew:** 2

- **Length:** 30 ft 8 in (9.35 m)

- **Wingspan:** 43 ft 4 in (13.21 m)

- **Height:** 11 ft 0 in (3.35 m)

- **Wing area:** 434 sq ft (40.3 m2)

- **Empty weight:** 2,387 lb (1,083 kg)

- **Gross weight:** 3,472 lb (1,575 kg)

- **Powerplant:** 1 × [Rolls-Royce Eagle VIII](/source/Rolls-Royce_Eagle_VIII) water-cooled [V12 engine](/source/V12_engine), 375 hp (280 kW) [Note 3]

**Performance**

- **Maximum speed:** 143 mph (230 km/h, 124 kn) at sea level [Note 4]

- **Endurance:** 3 hr 45 min

- **Service ceiling:** 22,000 ft (6,700 m)

- **Time to altitude:** 9 min to 10,000 ft (3,000 m)

**Armament**

- **Guns:** One fixed forward-firing .303 in (7.7 mm) [Vickers machine gun](/source/Vickers_machine_gun), 1 or 2 .303 in (7.7 mm) [Lewis guns](/source/Lewis_gun) on a [Scarff ring](/source/Scarff_ring)

- **Bombs:** 460 lb (210 kg) of bombs

## See also

- [1916 in aviation](/source/1916_in_aviation)

**Related development**

- [Airco DH.9](/source/Airco_DH.9)

- [Airco DH.9A](/source/Airco_DH.9A)

**Related lists**

- [List of bomber aircraft](/source/List_of_bomber_aircraft)

## References

### Notes

1. **[^](#cite_ref-28)** Quote: "Certainly the DH.4 was without peer among the day-bombing aeroplanes used by the aerial forces of any of the combatant nations."[22]

1. **[^](#cite_ref-34)** Sometimes derided as the "Flaming Coffin," *Gorrell's History of the Air Service of the AEF* refuted the misconception. Quote: "Of 33 DH-4s lost to enemy action by the US Air Service, eight fell in flames- no worse than the average at the time."[32]

1. **[^](#cite_ref-92)** 230 hp (170 kW) for [BHP Puma](/source/BHP_Puma)

1. **[^](#cite_ref-93)** 106 mph (171 km/h) for Puma engine variants

### Citations

1. ^ [***a***](#cite_ref-JacksonP58_1-0) [***b***](#cite_ref-JacksonP58_1-1) Jackson, 1987, p.58

1. **[^](#cite_ref-BruceP12_2-0)** Bruce, 1966, p.12

1. ^ [***a***](#cite_ref-BruceP3_3-0) [***b***](#cite_ref-BruceP3_3-1) [***c***](#cite_ref-BruceP3_3-2) [***d***](#cite_ref-BruceP3_3-3) [***e***](#cite_ref-BruceP3_3-4) [***f***](#cite_ref-BruceP3_3-5) [***g***](#cite_ref-BruceP3_3-6) [***h***](#cite_ref-BruceP3_3-7) Bruce, 1966, p.3

1. **[^](#cite_ref-JacksonP53_4-0)** Jackson, 1987, p.53

1. ^ [***a***](#cite_ref-BruceP4_5-0) [***b***](#cite_ref-BruceP4_5-1) [***c***](#cite_ref-BruceP4_5-2) [***d***](#cite_ref-BruceP4_5-3) [***e***](#cite_ref-BruceP4_5-4) Bruce, 1966, p.4

1. ^ [***a***](#cite_ref-BruceP3-4_6-0) [***b***](#cite_ref-BruceP3-4_6-1) [***c***](#cite_ref-BruceP3-4_6-2) Bruce, 1966, pp.3–4

1. ^ [***a***](#cite_ref-BruceP5_7-0) [***b***](#cite_ref-BruceP5_7-1) [***c***](#cite_ref-BruceP5_7-2) [***d***](#cite_ref-BruceP5_7-3) Bruce, 1966, p.5

1. ^ [***a***](#cite_ref-Mason_8-0) [***b***](#cite_ref-Mason_8-1) [***c***](#cite_ref-Mason_8-2) [***d***](#cite_ref-Mason_8-3) [***e***](#cite_ref-Mason_8-4) [***f***](#cite_ref-Mason_8-5) [***g***](#cite_ref-Mason_8-6) Mason, 1994, pp.66–69

1. **[^](#cite_ref-BruceP4-5_9-0)** Bruce, 1966, pp.4–5

1. ^ [***a***](#cite_ref-BruceP10_10-0) [***b***](#cite_ref-BruceP10_10-1) [***c***](#cite_ref-BruceP10_10-2) [***d***](#cite_ref-BruceP10_10-3) [***e***](#cite_ref-BruceP10_10-4) [***f***](#cite_ref-BruceP10_10-5) Bruce, 1966, p.10

1. **[^](#cite_ref-JacksonP54_11-0)** Jackson, 1987, p.54

1. **[^](#cite_ref-JacksonP60_12-0)** Jackson, 1987, p.60

1. ^ [***a***](#cite_ref-BruceP5-8_13-0) [***b***](#cite_ref-BruceP5-8_13-1) [***c***](#cite_ref-BruceP5-8_13-2) Bruce, 1966, pp.5–8

1. ^ [***a***](#cite_ref-BowersP3_14-0) [***b***](#cite_ref-BowersP3_14-1) [***c***](#cite_ref-BowersP3_14-2) Bowers, 1966, p.3

1. **[^](#cite_ref-BowersP3-10_15-0)** Bowers, 1966, pp.3, 10

1. **[^](#cite_ref-BowersP3-4_16-0)** Bowers, 1966, pp.3–4

1. **[^](#cite_ref-BowersP6-7_17-0)** Bowers, 1966, pp.6–7

1. **[^](#cite_ref-BowersP67_18-0)** Bowers, 1989, p.67

1. **[^](#cite_ref-BowersP7-8_19-0)** Bowers, 1966, pp.7–8

1. **[^](#cite_ref-BowersP9_20-0)** Bowers, 1966, p.9

1. **[^](#cite_ref-BowersP70_21-0)** Bowers, 1989, p.70

1. ^ [***a***](#cite_ref-BruceP507_22-0) [***b***](#cite_ref-BruceP507_22-1) [***c***](#cite_ref-BruceP507_22-2) [***d***](#cite_ref-BruceP507_22-3) Bruce, 1952, p.507

1. **[^](#cite_ref-BowersP7_23-0)** Bowers, 1966, p.7

1. ^ [***a***](#cite_ref-BruceP9_24-0) [***b***](#cite_ref-BruceP9_24-1) Bruce, 1966, p.9

1. **[^](#cite_ref-BruceP7-8_25-0)** Bruce, 1966, pp.7–8

1. ^ [***a***](#cite_ref-ThetNavyP86_26-0) [***b***](#cite_ref-ThetNavyP86_26-1) Thetford 1978, p.86

1. **[^](#cite_ref-BruceP9-10_27-0)** Bruce, 1966, pp.9–10

1. **[^](#cite_ref-JacksonP54-56_29-0)** Jackson, 1987, pp.54–56

1. ^ [***a***](#cite_ref-JacksonP56_30-0) [***b***](#cite_ref-JacksonP56_30-1) Jackson, 1987, p.56

1. **[^](#cite_ref-Maurer_31-0)** Maurer, 1979, pp.12, 87, 120, 132

1. **[^](#cite_ref-BowersP5-6_32-0)** Bowers, 1966, pp.5–6

1. **[^](#cite_ref-33)** Williams, 1999, p.83

1. **[^](#cite_ref-MaurerP551_35-0)** Maurer, 1979, p.551

1. **[^](#cite_ref-WilliamsP84_36-0)** Williams, 1999, p.84

1. **[^](#cite_ref-WilliamsP195_37-0)** Williams, 1999, p.195

1. **[^](#cite_ref-JacksonP77_38-0)** Jackson, 1987, p.77

1. **[^](#cite_ref-39)** ["Foreign Passenger-Carrying Aeroplanes Introduce a New Era of Transportation"](https://babel.hathitrust.org/cgi/pt?id=uc1.a0013490313&view=1up&seq=554). *Popular Mechanics Magazine*. **31**: 510–511. April 1919.

1. **[^](#cite_ref-40)** ["British Premier's Altered DH-4 Shows Unusual Speed"](https://babel.hathitrust.org/cgi/pt?id=uc1.a0013490321&view=1up&seq=131). *Popular Mechanics Magazine*. **32**: 65. July 1919.

1. **[^](#cite_ref-JacksonP81_41-0)** Jackson, 1987, p.81

1. ^ [***a***](#cite_ref-USAFFactsheet_42-0) [***b***](#cite_ref-USAFFactsheet_42-1) ["Fact Sheets: De Havilland DH-4."](http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?fsID=324) [Archived](https://web.archive.org/web/20090114034557/http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?fsID=324) 14 January 2009 at the [Wayback Machine](/source/Wayback_Machine) *National Museum of the USAF*. Retrieved: 19 April 2008.

1. ^ [***a***](#cite_ref-BowersP6_43-0) [***b***](#cite_ref-BowersP6_43-1) Bowers, 1966, p.6

1. **[^](#cite_ref-Workhorse_44-0)** ["The De Havilland DH-4, Workhorse of the Army Air Service."](http://www.airpower.au.af.mil/airchronicles/apj/apj02/win02/notam5.pdf) [Archived](https://web.archive.org/web/20080528183809/http://www.airpower.au.af.mil/airchronicles/apj/apj02/win02/notam5.pdf) 28 May 2008 at the [Wayback Machine](/source/Wayback_Machine) *Air & Space Power Journal*, Winter 2002. Retrieved: 9 May 2008.

1. **[^](#cite_ref-45)** ["Robert Guy Robinson, First Lieutenant, United States Marine Corps."](http://www.arlingtoncemetery.net/rrobin.htm) [Archived](https://web.archive.org/web/20080905202456/http://www.arlingtoncemetery.net/rrobin.htm) 5 September 2008 at the [Wayback Machine](/source/Wayback_Machine) at ArlingtonCemetery.net (Unofficial website).

1. **[^](#cite_ref-AngelucciP79_46-0)** Angelucci, 1981, p.79

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1. **[^](#cite_ref-49)** ["Fact Sheets: Air-to-Air Refueling."](http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=745) [Archived](https://web.archive.org/web/20130318015424/http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=745) 18 March 2013 at the [Wayback Machine](/source/Wayback_Machine) *National Museum of the United States Air Force*. Retrieved: 10 May 2008.

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1. ^ [***a***](#cite_ref-SwanNavyP156_51-0) [***b***](#cite_ref-SwanNavyP156_51-1) Swanborough and Bowers, 1976, p.156

1. **[^](#cite_ref-52)** Hearst Magazines (November 1929). ["Help From The Skies"](https://books.google.com/books?id=0N8DAAAAMBAJ&pg=PA765). *Popular Mechanics*. Hearst Magazines. p. 765.

1. **[^](#cite_ref-CivilSince1919P41_53-0)** Jackson, 1973, p.41

1. **[^](#cite_ref-DHsince1909P79_54-0)** Jackson, 1987, p.79

1. **[^](#cite_ref-CivilSince1919P43_55-0)** Jackson, 1973, p.43

1. **[^](#cite_ref-56)** "24-cent DeHavilland Biplane". Smithsonian National Postal Museum.

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1. **[^](#cite_ref-DHsince1909P70-71_58-0)** Jackson, 1973, pp.70–71

1. ^ [***a***](#cite_ref-Postal_59-0) [***b***](#cite_ref-Postal_59-1) Pope, Nancy A. ["deHavilland DH-4"](https://web.archive.org/web/20150706021849/http://postalmuseum.si.edu/exhibits/current/airmail-in-america/the-airplanes/dehavilland-dh-4.html). [National Postal Museum](/source/National_Postal_Museum), [Smithsonian Institution](/source/Smithsonian_Institution). Archived from [the original](http://postalmuseum.si.edu/exhibits/current/airmail-in-america/the-airplanes/dehavilland-dh-4.html) on 6 July 2015. Retrieved 21 July 2015.

1. **[^](#cite_ref-BowersP9-10_60-0)** Bowers, 1966, pp.9–10

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1. **[^](#cite_ref-74)** ["1917 Airco DH.4 (British Military)"](http://century-aviation.com/essential_grid/1917-airco-dh-4-british-military). *Century Aviation*. [Archived](https://web.archive.org/web/20161011192953/http://century-aviation.com/essential_grid/1917-airco-dh-4-british-military/) from the original on 11 October 2016. Retrieved 10 May 2016.

1. **[^](#cite_ref-75)** ["Fotografía De Havilland DH-4"](https://web.archive.org/web/20160318103450/http://www.ejercitodelaire.mde.es/ea/pag?idDoc=CC080F0B0240A9D7C125747A002415EA&idImg=DA4CA2CBC2AED670C125747A0024C05F). *Ejército del Aire*. Archived from [the original](http://www.ejercitodelaire.mde.es/ea/pag?idDoc=CC080F0B0240A9D7C125747A002415EA&idImg=DA4CA2CBC2AED670C125747A0024C05F) on 18 March 2016. Retrieved 10 May 2016.

1. **[^](#cite_ref-76)** ["Airframe Dossier – Airco DH-4"](http://aerialvisuals.ca/AirframeDossier.php?Serial=2981). *Aerial Visuals*. AerialVisuals.ca. [Archived](https://web.archive.org/web/20161012133859/http://aerialvisuals.ca/AirframeDossier.php?Serial=2981) from the original on 12 October 2016. Retrieved 10 May 2016.

1. **[^](#cite_ref-77)** ["deHavilland DH-4"](https://web.archive.org/web/20160417222726/http://postalmuseum.si.edu/exhibits/current/airmail-in-america/the-airplanes/dehavilland-dh-4.html). *Smithsonian National Postal Museum*. Archived from [the original](http://postalmuseum.si.edu/exhibits/current/airmail-in-america/the-airplanes/dehavilland-dh-4.html) on 17 April 2016. Retrieved 10 May 2016.

1. **[^](#cite_ref-78)** Cromwell, Bob (15 October 2014). ["National Park Service Announces the Purchase of a DeHavilland DH-4 Biplane for Exhibit at Pearson Air Museum"](https://www.nps.gov/fova/learn/news/dehavillandexhibit.htm). *National Park Service*. [Archived](https://web.archive.org/web/20160919014750/https://www.nps.gov/fova/learn/news/dehavillandexhibit.htm) from the original on 19 September 2016. Retrieved 10 May 2016.

1. **[^](#cite_ref-79)** ["1919 DeHavilland DH-4B"](http://century-aviation.com/essential_grid/1919-dehavilland-dh-4b). *Century Aviation*. [Archived](https://web.archive.org/web/20160423190911/http://century-aviation.com/essential_grid/1919-dehavilland-dh-4b/) from the original on 23 April 2016. Retrieved 13 August 2016.

1. **[^](#cite_ref-80)** ["The DH-4 Liberty Plane at War and in Peace"](https://www.nps.gov/articles/libertyplane.htm). *National Park Service*. Retrieved 13 December 2023.

1. **[^](#cite_ref-81)** ["De Havilland DH-4"](https://www.nationalmuseum.af.mil/Visit/Museum-Exhibits/Fact-Sheets/Display/Article/197397/de-havilland-dh-4/). *National Museum of the US Air Force*. 7 April 2015. [Archived](https://web.archive.org/web/20160605032142/http://www.nationalmuseum.af.mil/Visit/MuseumExhibits/FactSheets/Display/tabid/509/Article/197397/de-havilland-dh-4.aspx) from the original on 5 June 2016. Retrieved 10 May 2016.

1. **[^](#cite_ref-82)** ["DeHavilland DH-4B"](http://century-aviation.com/essential_grid/dehavilland-dh-4b). *Century Aviation*. [Archived](https://web.archive.org/web/20160423190206/http://century-aviation.com/essential_grid/dehavilland-dh-4b/) from the original on 23 April 2016. Retrieved 10 May 2016.

1. **[^](#cite_ref-83)** ["1918 DeHavilland DH-4 Mail Plane"](http://century-aviation.com/essential_grid/1918-dehavilland-dh-4-mail-plane). *Century Aviation*. [Archived](https://web.archive.org/web/20160428190047/http://century-aviation.com/essential_grid/1918-dehavilland-dh-4-mail-plane/) from the original on 28 April 2016. Retrieved 10 May 2016.

1. **[^](#cite_ref-84)** ["1918 De Havilland DH-4 (U.S. Army Air Corps)"](http://century-aviation.com/essential_grid/1918-de-havilland-dh-4-u-s-army-air-corps). *Century Aviation*. [Archived](https://web.archive.org/web/20160423002225/http://century-aviation.com/essential_grid/1918-de-havilland-dh-4-u-s-army-air-corps/) from the original on 23 April 2016. Retrieved 10 May 2016.

1. **[^](#cite_ref-85)** ["Airframe Dossier – Airco DH-4, c/r N3258"](http://aerialvisuals.ca/AirframeDossier.php?Serial=70390). *Aerial Visuals*. AerialVisuals.ca. [Archived](https://web.archive.org/web/20161012133848/http://aerialvisuals.ca/AirframeDossier.php?Serial=70390) from the original on 12 October 2016. Retrieved 10 May 2016.

1. **[^](#cite_ref-86)** Skaarup, Harold (1 February 2002). [*Washington Warbird Survivors 2002: A Handbook on Where to Find Them*](https://books.google.com/books?id=qHvpxhDOzJAC). iUniverse. [ISBN](/source/ISBN_(identifier)) [9780595216932](https://en.wikipedia.org/wiki/Special:BookSources/9780595216932).

1. **[^](#cite_ref-87)** ["Museum Hangar 4"](http://www.historicaircraftrestorationmuseum.org/museumhangar4.html). *Historic Aircraft Restoration Museum*. [Archived](https://web.archive.org/web/20160306220901/http://www.historicaircraftrestorationmuseum.org/museumhangar4.html) from the original on 6 March 2016. Retrieved 11 May 2016.

1. **[^](#cite_ref-88)** ["Airframe Dossier – Airco DH-4M-2A, c/r N3249H"](http://aerialvisuals.ca/AirframeDossier.php?Serial=141812). *Aerial Visuals*. AerialVisuals.ca. [Archived](https://web.archive.org/web/20161012133829/http://aerialvisuals.ca/AirframeDossier.php?Serial=141812) from the original on 12 October 2016. Retrieved 10 May 2016.

1. **[^](#cite_ref-89)** ["FAA Registry \[N3249H\]"](http://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=N3249H). *Federal Aviation Administration*. U.S. Department of Transportation. Retrieved 3 November 2021.

1. **[^](#cite_ref-90)** ["DH-4M2"](http://www.peckaeroplanerestoration.com/projects/dh-4-mail-plane). *Peck Aeroplane Restoration*. [Archived](https://web.archive.org/web/20160920091101/http://www.peckaeroplanerestoration.com/projects/dh-4-mail-plane/) from the original on 20 September 2016. Retrieved 3 June 2016.

1. **[^](#cite_ref-BruceP8-10_91-0)** Bruce, 1966, pp.8, 10

### Bibliography

- Angelucci, Enzo, ed. *World Encyclopedia of Military Aircraft*. London: Jane's, 1991. [ISBN](/source/ISBN_(identifier)) [0-7106-0148-4](https://en.wikipedia.org/wiki/Special:BookSources/0-7106-0148-4).

- Bruce, J.M. ["The De Havilland D.H.4."](https://web.archive.org/web/20110520132120/http://www.flightglobal.com/pdfarchive/view/1952/1952%20-%203038.html) [*Flight*](/source/Flight_International), 17 October 1952, pp. 506–510.

- Bruce, J.M. *The de Havilland D.H.4. (Aircraft in Profile number 26)*. London: Profile Publications, 1966. No ISBN.

- Bowers, Peter M. *Boeing Aircraft since 1916*. London: Putnam, Second edition, 1989. [ISBN](/source/ISBN_(identifier)) [0-85177-804-6](https://en.wikipedia.org/wiki/Special:BookSources/0-85177-804-6).

- Bowers, Peter M. *The American DH.4 (Aircraft in Profile number 97)*. London: Profile Publications, 1966. No ISBN.

- Jackson, A.J. *British Civil Aircraft since 1919: Volume 2*. London: Putnam, Second edition, 1973. [ISBN](/source/ISBN_(identifier)) [0-370-10010-7](https://en.wikipedia.org/wiki/Special:BookSources/0-370-10010-7).

- Jackson, A.J. *De Havilland Aircraft since 1909*. London: Putnam, Third edition, 1987. [ISBN](/source/ISBN_(identifier)) [0-85177-802-X](https://en.wikipedia.org/wiki/Special:BookSources/0-85177-802-X).

- Klaauw, Bart van der (March–April 1999). "Unexpected Windfalls: Accidentally or Deliberately, More than 100 Aircraft 'arrived' in Dutch Territory During the Great War". *Air Enthusiast* (80): 54–59. [ISSN](/source/ISSN_(identifier)) [0143-5450](https://search.worldcat.org/issn/0143-5450).

- Mason, Francis K. *The British Bomber since 1914*. London: Putnam Aeronautical Books, 1994. [ISBN](/source/ISBN_(identifier)) [0-85177-861-5](https://en.wikipedia.org/wiki/Special:BookSources/0-85177-861-5).

- Maurer, Maurer, ed. *The U.S. Air Service in World War I: Volume IV Postwar Review*. Washington, D.C.: The Office of Air Force History Headquarters USAF, 1979.

- Prins, François (Spring 1994). "Pioneering Spirit: The QANTAS Story". *[Air Enthusiast](/source/Air_Enthusiast)*. No. 53. pp. 24–32. [ISSN](/source/ISSN_(identifier)) [0143-5450](https://search.worldcat.org/issn/0143-5450).

- Sturtivant, Ray and Gordon Page. *The D.H.4/D.H.9 File*. Tonbridge, Kent, UK: Air-Britain (Historians) Ltd., 2000. [ISBN](/source/ISBN_(identifier)) [0-85130-274-2](https://en.wikipedia.org/wiki/Special:BookSources/0-85130-274-2).

- Swanborough, F.G. and Peter M. Bowers. *United States Military Aircraft since 1909*. London: Putnam, 1963.

- Swanborough Gordon and Peter M. Bowers. *United States Naval Aircraft since 1911*. London: Putnam, Second edition, 1976. [ISBN](/source/ISBN_(identifier)) [0-370-10054-9](https://en.wikipedia.org/wiki/Special:BookSources/0-370-10054-9).

- Thetford, Owen. *British Naval Aircraft since 1912*. London: Putnam, Fourth edition, 1978. [ISBN](/source/ISBN_(identifier)) [0-370-30021-1](https://en.wikipedia.org/wiki/Special:BookSources/0-370-30021-1).

- Thomas, Andrew. "In the Footsteps of Daedulus: Early Greek Naval Aviation". *Air Enthusiast*, No. 94, July–August 2001, pp. 8–9. [ISSN](/source/ISSN_(identifier)) [0143-5450](https://search.worldcat.org/issn/0143-5450)

- *United States Air Force Museum Guidebook*. Wright-Patterson AFB, Ohio: Air Force Museum Foundation, 1975.

- Wauthy, Jean-Luc & de Neve, Florian (June 1995). "Les aéronefs de la Force Aérienne Belge, deuxième partie 1919–1935" [Aircraft of the Belgian Air Force]. *Le Fana de l'Aviation* (in French) (305): 28–33. [ISSN](/source/ISSN_(identifier)) [0757-4169](https://search.worldcat.org/issn/0757-4169).

- Williams, George K. *Biplanes and Bombsights: British Bombing in World War I*. Maxwell Air Force Base, Alabama: Air University Press, 1999. [ISBN](/source/ISBN_(identifier)) [1-4102-0012-4](https://en.wikipedia.org/wiki/Special:BookSources/1-4102-0012-4).

## External links

Wikimedia Commons has media related to [Airco DH.4](https://commons.wikimedia.org/wiki/Category:Airco_DH.4).

- ["Pilot Report, The deHavilland DH4: A Trip Back In Time,"](http://www.opencockpit.net/dh4/dh4.html) by Addison Pemberton

- ["Chapter 3: The Airco/deHavilland DH-4,"](http://harris1.net/hold/av/avhist/a8/a8_dh4.htm) in *Eight Great Aircraft,* by Richard Harris.

v t e de Havilland and Airco aircraft de Havilland numerical sequence Biplane No.1 Biplane No.2 DH.1 DH.2 DH.3 DH.4 DH.5 DH.6 DH.9 / DH.9A / DH.9C DH.10 DH.11 DH.12 DH.14 DH.15 DH.16 DH.17 DH.18 DH.19 DH.20 DH.21 DH.22 DH.23 DH.24 DH.25 DH.26 DH.27 DH.28 DH.29 DH.30 DH.31 DH.32 DH.33 DH.34 DH.35 DH.36 DH.37 DH.38 DH.39 DH.40 DH.41 DH.42 DH.43 DH.44 DH.45 DH.46 DH.47 DH.48 DH.49 DH.50 DH.51 DH.52 DH.53 DH.54 DH.55 DH.56 DH.57 DH.58 DH.59 DH.60 DH.61 DH.62 DH.63 DH.64 DH.65 DH.66 DH.67 DH.68 DH.69 DH.70 DH.71 DH.72 DH.73 DH.74 DH.75 DH.76 DH.77 DH.78 DH.79 DH.80 DH.81 DH.82 DH.83 DH.84 DH.85 DH.86 DH.87 DH.88 DH.89 DH.90 DH.91 DH.92 DH.93 DH.94 DH.95 DH.96 DH.97 DH.98 DH.99 DH.100 DH.101 DH.102 DH.103 DH.104 DH.105 DH.106 DH.108 DH.110 DH.112 DH.113 DH.114 DH.115 DH.116 DH.118 DH.119 DH.120 DH.121 DH.122 DH.123 DH.125 DH.126 By name Albatross Amiens Canberra Cirrus Moth Comet (jet) Comet Derby Devon Dolphin Dominie Don Doncaster Dove Dragon Dragon Rapide Dragonfly Express Hercules Flamingo Fox Moth Gazelle Genet Moth Giant Moth (DH.50) Giant Moth (DH.61) Gipsy Moth Hawk Moth Hermes Moth Heron Highclere Hornet Hornet Moth Humming Bird Leopard Moth Mantis Menasco Moth Metal Moth Mosquito Moth Moth Major Moth Minor Moth Trainer M'pala Ninack Okapi Oxford Puss Moth Queen Bee Sea Vixen Sea Venom Tiger Moth (DH.71) Tiger Moth (DH.82) Trident Vampire Venom By role Fighters DH.1 DH.2 DH.5 DH.77 DH.98 Mosquito DH.100 Vampire DH.103 Hornet DH.110 Sea Vixen DH.112 Venom DH.112 Sea Venom DH.113 Vampire Night Fighter DH.116 Bombers DH.1 DH.3 DH.4 DH.9/M'pala/Mantis DH.9A Ninack DH.10 Amiens DH.11 Oxford DH.14 Okapi DH.27 Derby DH.72 Canberra DH.98 Mosquito Passenger DH.4A DH.9B DH.9C DH.16 DH.18 DH.29 Doncaster DH.32 DH.34 DH.50 Giant Moth DH.54 Highclere DH.61 Giant Moth DH.66 Hercules DH.83 Fox Moth DH.84 Dragon DH.86 Express DH.89 Dragon Rapide DH.89 Dominie DH.90 Dragonfly DH.91 Albatross DH.92 Dolphin DH.95 Flamingo DH.96 DH.104 Dove DH.104 Devon DH.106 Comet DH.114 Heron DH.121 Trident DH.125 Sports DH.51 DH.75 Hawk Moth DH.53 Humming Bird DH.60 Moth DH.60 Cirrus Moth DH.60 Hermes Moth DH.60 Genet Moth DH.60G Gipsy Moth DH.60M Metal Moth DH.60GIII Moth Major DH.80 Puss Moth DH.85 Leopard Moth DH.87 Hornet Moth Trainers DH.6 DH.60 Moth DH.60G Gipsy Moth DH.60T Moth Trainer DH.82 Tiger Moth DH.82C-2/C-4 Menasco Moth DH.93 Don DH.94 Moth Minor DH.115 Vampire Trainer Racers DH.4R DH.9R DH.71 Tiger Moth DH.88 Comet Experimental DH.15 Gazelle Drones DH.82 Queen Bee Technical school T.K.1 T.K.2 T.K.3 T.K.4 T.K.5

v t e Boeing aircraft model numbers Aircraft 1 2 3 4 5 6 6D/E 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 220 221 222 223 224 225 226 227 228 229 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 276 277 278 279 280 281 282 283 284 285 286 287 288 290 291 292 293 294 295 296 297 298 299 300 302 303 304 305 306 307 308 309 311 312 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 345-2/4/31 346 348 349 350 351 352 353 354 355 356 357 358 359 361 362 363 364 365 366 367 -76 367-80 368 369 370 371 372 373 374 375 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 431 432 433 434 435 436 437 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 479 480 481 482 483 484 485 486 490 493 495 497 498 701 707 -020 717 (I) -100/146/148/166 717 (II) 720 727 733 737 -253 Classic Next Generation -700W -800A MAX 739 747 SP -2G4B -400 -4G4F -8 757 -2G4 767 777 X 787 814 815 818 820 831 844 853-21 953 1041 1044 1046 1074 1080 2000 2020 2707 Turbine engines 8C 500 502 520 550 Missiles 600 601 602 621 624 631 641 Vessels 929 Other Boeing customer codes

v t e Lowe, Willard & Fowler (L-W-F) aircraft LWF designs V V-1 V-2 V-3 VH-1 Seagull F F-7 Reconnaissance Mailplane G H Owl J-2 Twin DH L Butterfly MO-1 XT-3 XNBS-2 Built under licence Curtiss HS-2L Douglas DT-2 Martin/LWF NBS-1

v t e Robertson and Wren aircraft Robertson B1-RD CG-4L DH-4R JNR OrioleR S.VIIR Skylark SRX-1 Standard JR Wren Wren 460 O-4 L Built under license R Re-manufactured Curtiss-Robertson aircraft are listed here.

v t e USAAS observation aircraft Night observation NO-1 NO-2 Artillery observation AO-1 Corps observation CO-1 CO-2 CO-3 CO-4 CO-5 CO-6 CO-7 CO-8

v t e USN observation aircraft designations, pre-1962 Observation Boeing OB O2B Curtiss OC O2C O3C Douglas OD O2D Elias EO Cessna OE Grumman OF Huff-Daland HO Berliner-Joyce OJ Keystone OK Loening OL O2L Martin MO M2O O3M Naval Aircraft Factory NO O2N Viking OO Pitcairn OP-1 OP-2 Vought UO O2U O3U O4U O5U Stinson OY Pennsylvania Aircraft OZ Observation Scout Edo OSE Naval Aircraft Factory OSN OS2N Stearman OSS Vought OSU OS2U

Authority control databases: National United States Israel

---
Adapted from the Wikipedia article [Airco DH.4](https://en.wikipedia.org/wiki/Airco_DH.4) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Airco_DH.4?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.