Engineering:Douglas XA-2
| XA-2 | |
|---|---|
| |
| Douglas XA-2 with removed cowling on the lower nose to enhance engine cooling | |
| Role | Attack aircraft |
| National origin | United States |
| Manufacturer | Douglas Aircraft Company |
| Status | Prototype |
| Primary user | United States Army Air Corps |
| Number built | 1 |
| Developed from | Douglas O-2 |
The Douglas XA-2 was an American prototype attack aircraft converted from a Douglas O-2 observation aircraft in the spring of 1926 by Douglas Aircraft. Only one prototype aircraft was built and the type was not ordered into production.
Design and development
One Douglas O-2, serial number 25-380, was modified for the new role as an attack aircraft. While the basic structure of the aircraft remained, there were several modifications made. The water-cooled Liberty engine (V-1650) of the O-2 was replaced by an inverted air-cooled Allison VG-1410 engine. The reason for this was that a water cooling system was seen as too vulnerable to enemy attack. The lower engine cowlings were omitted to allow for more cooling air flow over the engine. Second, the A-2 was more heavily armed than the O-2. The A-2 had six forward-firing .30-caliber Browning machine guns - two in the nose forward of the cockpit, and two each in the mid-upper and lower wings. Two .30-caliber Lewis guns were put on a flexible mount for use by the observer-gunner in rear defense of the aircraft. The aircraft also had the capacity for a small bomb load of 100 lb (45 kg).
The Douglas XA-2 was evaluated against the Curtiss XA-3 (a conversion of the Curtiss O-1B observation plane). The Douglas Aircraft won the initial competition, but the Army realized that the Liberty engine was both underpowered and in dwindling supply. It ordered a second competition with both models upgraded with Packard 1A-1500 engines. The Curtiss aircraft won this time and became the U.S. Army Air Corps' frontline attack aircraft (Curtiss A-3 Attack Falcon) from 1928 to 1935.
Operators
United States
- United States Army Air Corps
Specifications (XA-2)
General characteristics
- Crew: Two (pilot & observer / gunner)
- Length: 29 ft 7 in (9.02 m)
- Wingspan: 39 ft 8 in (12.09 m)
- Height: 11 ft (3.4 m)
- Max takeoff weight: 4,985 lb (2,261 kg)
- Powerplant: 1 × Allison VG-1410 inverted air-cooled V-12 piston engine, 433 hp (323 kW)
Performance
- Maximum speed: 130 mph (210 km/h, 110 kn)
- Cruise speed: 100 mph (160 km/h, 87 kn)
- Range: 400 mi (640 km, 350 nmi)
- Service ceiling: 15,000 ft (4,600 m)
Armament
- Guns:
- 6 × forward firing .30-cal. (7.62 mm) Browning machine guns, two in the fuselage + one in each wing
- 2 × flexible .30-cal. Lewis machine guns
- Bombs: Provision for 100 lb (45 kg) of bombs mounted on lower wing racks
See also
Related development
Aircraft of comparable role, configuration and era
- A-3 Falcon
Related lists
- List of military aircraft of the United States
References
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