Douglas XA-2

XA-2
Douglas XA-2 with removed cowling on the lower nose to enhance engine cooling
Role	Attack
National origin	United States
Manufacturer	Douglas
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 (209 km/h; 113 kn)
• Cruise speed: 100 mph (87 kn; 161 km/h)
• Range: 400 mi (348 nmi; 644 km)
• Service ceiling: 15,000 ft (4,572 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

Wikimedia Commons has media related to Douglas XA-2.

Related development

• Douglas O-2

Aircraft of comparable role, configuration and era

• A-3 Falcon

Related lists

• List of military aircraft of the United States