Dormoy 1919 biplane

Designed by Etienne Dormoy in 1919 as a single place open cockpit biplane experiment in ultralights. A basic framework with wings and a pilot’s seat behind the 18hp Henderson motor. The idea was carried over into Dormoy Bathtub.

Flown successfully at Selfridge Field, Detroit, only the one was built, sometimes listed as a Packard Motor Co product but actually spare-time project by Dormoy and his co-workers while employed there.

Dorand Biplan-Laboratoire

A design specially built for the testing of several components, like wings and propellers. The machine was loaded with all sorts of measurement instruments. As this was far before the time of automatic registration, these instruments were photographed in flight. At that time glass plate negatives were used for photographing. Interpretation was made on the ground.

The machine dates from 1910 (although first described in L’Aérophile 1912) and was continuously modified if needed for the tests. Dorand was an old hand in aeronautics as he was already assigned commander of the Établissement Aérostatique at Chalais-Meudon in 1894.

Dorand AR.1 / AR.2 / ARL.2

The Dorand AR.1 was a World War I French two-seat observation biplane aircraft used by the French Air Force, the American Expeditionary Force and, in small numbers, by Serbian Aviation.

Designed by Captain Georges Lepère of the STAé to replace the obsolescent Farman F.40 pusher aircraft, Dorand AR-series were two-seater reconnaissance biplanes that were named after the STAé director, Lt. Col. Dorand. They were characterized by backward-staggered two-bay wings and angular all-moving tail surfaces. The pilot sat beneath the leading edge of the upper wing, with the observer’s cockpit being under the trailing edge, and there were cut-outs in both wings to improve the latter’s field of view. Rather unusually for a single-engine tractor biplane of the era, the lower wing was not directly attached to the fuselage, instead being somewhat below it, supported by struts.

Dorand AR.1

Production of these aircraft began in a state-owned French Army Aircraft Establishment (or S.T.Aé.) factory at Chalais-Meudon, near Paris, after flight testing had been completed in the autumn 1916.

The first of the thirteen squadrons which flew Dorands on the Western Front received their aircraft in the spring 1917. Five other French squadrons used the type on the Italian Front. These aircraft were withdrawn from the combat units in early 1918.

In 1917 the American Expeditionary Force ordered the Renault-engined varieties of the Dorand, the first of 22 AR.1s being delivered in December 1917 and the first of 120 AR.2s in following February. The Americans operated these types on the Western Front for the first half 1918, until replacing them with the Salmson 2. After being retired from fighting duties, the surviving examples were used as trainers.

A small number of Dorand AR.1s were also supplied to Kingdom of Serbia, which operated these aircraft in four squadrons from April 1918 onwards.

Dorand AR.2’s of the first Serbian squadron

While the Dorand AR-types didn’t have a particularly distinguished career in either French or American service, having a rather mediocre performance for a late-war daytime reconnaissance aircraft and suffering from having low priority for engine supplies, it is a testimony to the general soundness of the design that after the war, many AR.1s and AR.2s appeared in the French civil register, being used as 2/3-passenger transports by companies like Compagnie Aérienne Française and Réseau Aérien Transafricain. Private users found the aircraft useful for training and joy-flights as well.

All these types had “A.2” added to their names in French service, indicating that they were two-seater reconnaissance aircraft.

1917

Variants:

AR.1 A2 160
Early production version, frontal radiators
Engine: 120 kW (160 hp) Renault 8Gd
Wing span: 13.27 m (43.5 ft)

AR.1 A2 200
Mid production version, frontal radiators
Engine: 150 kW (200 hp) Renault 8Gdy
Propeller: 2-bladed wooden fixed pitch
Wing span: 13.27 m (43.5 ft)
Wing area: 50.36 m2 (542.1 sq ft)
Length: 8.225 m (27 ft 0 in)
Empty weight: 890 kg (1,962 lb)
Gross weight: 1,330 kg (2,932 lb)
Wing loading: 26.4 kg/m2 (5.4 lb/sq ft)
Power/mass: 0.143 kW/kg (0.087 hp/lb)
Fuel capacity: 170 L (37 imp gal)
Maximum speed: 148 km/h (92 mph, 80 kn) at 2,000 m (6,600 ft)
Endurance: 3 hours
Service ceiling: 5,500 m (18,000 ft)
Crew: 2 (pilot and observer)
Armament: 1 × fixed forward-firing 7.7 mm (.303 in) Vickers mg / 1 or 2 × 7.7 mm (.303 in) Lewis gun(s) for observer

AR.1 A2 190
Late production version, frontal radiators
Engine: 140 kW (190 hp) Renault 8Gd
Wing span: 13.27 m (43.5 ft)

ARL.1 A2
AR.1s modified, frontal radiators
Engine: 180 kW (240 hp) Lorraine-Dietrich
Wing span: 13.27 m (43.5 ft)

AR.1 D2
Trainers, frontal radiators
Engine: Renault 12d
Wing span: 13.27 m (43.5 ft)

AR.2 A2
2nd production version, wing mounted radiators
Engine: 148 kW (199 hp) Renault 8Ge
Wingspan: 12.0 m (39.4 ft)
Wing area: 45 sq.m

ARL.2 A2
AR.2s modified, wing mounted radiators
Engine: 180 kW (240 hp) Lorraine-Dietrich
Wingspan: 12.0 m (39.4 ft)
Wing area: 45 sq.m

Doppelraab IV

Designed by Fritz Raab. A 1950 glider trainer that was well used after the war because its compactness and low cost. The instructor seat was elevated and had no controls. The instructor having to reach over the students shoulders to take the controls.

Wing span: 12.76m
Wing area: 18sq.m
Length: 29.692 ft / 9.05 m
Empty Weight: 185kg
Gross Weight: 350kg
Wing Load: 19.4kg/sq.m
Aspect ratio: 9.05
Airfoil: Go 550
MinSink: 0.85 m/s 50 kph
L/DMax: 20 @ 55 kph
No. of Seats: 2
No. Built: 220

Donohoe Shuttle

Dave Donohoe, a colleague of Tom Cadet, developed the Boorabee’s airfoil. This wing was mated to a new fuselage mould to use a 4 x 3 inch rectangular boom and Dave called the result the Shuttle. Similar in overall appearance, the Shuttle has a single wing strut and a different tail and undercarriage and control system. After the undercarriage of the Shuttle proved weak, some Shuttles adopted that of the Boorabee.

The Shuttle design was abandoned after Dave’s second aircraft, powered by a 1600cc Jabiru, developed aileron flutter. The wings were damaged extensively, but Dave was able to land the aircraft. Vibration from the Jabiru, coupled with a control system that was too slack, caused the flutter.