• Source: Keystone B-3

The 3/info/keystone" target="_blank">Keystone 3/info/b" target="_blank">B-3A was a bomber aircraft developed for the United States Army Air Corps by 3/info/keystone" target="_blank">Keystone Aircraft in the late 1920s.




Design and development


The 3/info/b" target="_blank">B-3 was originally ordered as the LB-10A (a single-tail modification of the 3/info/keystone" target="_blank">Keystone LB-6), but the Army dropped the LB- 'light bomber' designation in 1930.
Although the performance of the 3/info/b" target="_blank">B-3A was hardly better than that of the bombers flown at the end of World War I, it had come a long way in terms of flight safety.




Operational history


The 3/info/b" target="_blank">B-3A was a member of the last family of biplanes operated by the US Army; it remained in service until 1940. A few years after it was first produced, the introduction of all-metal monoplanes rendered it almost completely obsolete.




Variants


LB-10
The last of the 17 LB-6s ordered (S/N 29-27) was converted with a re-designed single fin and rudder and two 525 hp Wright R-1750E engines. Delivered to Wright Field on 7 July 1929, it was wrecked on 12 November 1929.
LB-10A
This version used Pratt and Whitney R-1690-3 Hornet engines and was slightly smaller, in both wingspan and length. A total of 63 were ordered (S/N 30-281/343). All were re-designated as the 3/info/b" target="_blank">B-3A before any deliveries were made, with the final 27 built as 3/info/b" target="_blank">B-5A with Wright engines.
3/info/b" target="_blank">B-3A
Ordered as LB-10A, 36 delivered as 3/info/b" target="_blank">B-3A (S/N 30-281/316). The first aircraft was delivered in October 1930.
3/info/b" target="_blank">B-5A
Ordered as 3/info/b" target="_blank">B-3A, re-engined with Wright R-1750-3 Cyclone engines, 27 built (S/N 30-317/343).




Operators


United States
United States Army Air Corps
2d Bombardment Group, Langley Field, Virginia
20th Bomb Squadron – operated 3/info/b" target="_blank">B-3A and 3/info/b" target="_blank">B-5A 1931–1932
49th Bomb Squadron – operated 3/info/b" target="_blank">B-3A and 3/info/b" target="_blank">B-5A 1931–1932
96th Bomb Squadron – operated 3/info/b" target="_blank">B-3A and 3/info/b" target="_blank">B-5A 1931–1932
4th Composite Group, Nichols Field, Luzon, Philippines
28th Bomb Squadron – operated 3/info/b" target="_blank">B-3A 1932–1937
2nd Observation Squadron- operated 3/info/b" target="_blank">B-3A 1938–1940
5th Composite Group, Luke Field, Territory of Hawaii
23d Bomb Squadron – operated 3/info/b" target="_blank">B-5A 1932–1937
72d Bomb Squadron – operated 3/info/b" target="_blank">B-5A 1932–1936
6th Composite Group, France Field, Panama Canal Zone
25th Bomb Squadron – operated 3/info/b" target="_blank">B-3A 1932–1936
7th Bombardment Group, March Field, California
9th Bomb Squadron – operated 3/info/b" target="_blank">B-3A 1931–1934
11th Bomb Squadron – operated 3/info/b" target="_blank">B-3A 1931–1934
31st Bomb Squadron – operated 3/info/b" target="_blank">B-3A 1931–1934
19th Bombardment Group, Rockwell Field, California
30th Bomb Squadron – operated 3/info/b" target="_blank">B-3A 1932–1936
32d Bomb Squadron – operated 3/info/b" target="_blank">B-3A 1932–1935
Air Corps Advanced Flying School, Kelly Field, Texas
42d Bomb Squadron – operated 3/info/b" target="_blank">B-3A and 3/info/b" target="_blank">B-5A 1935–1936
Philippines
Philippine Army Air Corps
10th Bombardment Squadron




Specifications (3/info/b" target="_blank">B-3A)


General characteristics

Crew: 5
Length: 48 ft 10 in (14.9 m)
Wingspan: 74 ft 8 in (22.8 m)
Height: 15 ft 9 in (4.8 m)
Wing area: 1,145 sq ft (106.4 m2)
Empty weight: 7,705 lb (3,495 kg)
Gross weight: 12,952 lb (5,875 kg)
Powerplant: 2 × Pratt & Whitney R-1690-3 radial engines, 525 hp (392 kW) each
Performance

Maximum speed: 114 mph (183 km/h, 98 kn)
Cruise speed: 98 mph (158 km/h, 85 kn)
Range: 860 mi (1,400 km, 760 nmi)
Service ceiling: 12,700 ft (3,870 m)
Rate of climb: 530 ft/min (2.7 m/s)
Wing loading: 11.31 lb/sq ft (55.42 kg/m2)
Power/mass: 0.0811 hp/lb (133 W/kg)
Armament

Guns: 3 × .30 in (7.62 mm) machine guns
Bombs: 2,500 lb (1,100 kg); 4,000 lb (1,800 kg) on short runs




See also



Related development

3/info/keystone" target="_blank">Keystone LB-6
3/info/keystone" target="_blank">Keystone 3/info/b" target="_blank">B-4
3/info/keystone" target="_blank">Keystone 3/info/b" target="_blank">B-5
3/info/keystone" target="_blank">Keystone 3/info/b" target="_blank">B-6

Related lists

List of bomber aircraft
List of military aircraft of the United States




References


Notes

Bibliography




External links



Encyclopedia of American Aircraft
Photograph of 3/info/b" target="_blank">B-3 on the ground
Photograph of 3/info/b" target="_blank">B-3 landing
USAF Museum article on LB-10
USAF Museum article on 3/info/b" target="_blank">B-3

Kata Kunci Pencarian:

• Pennsylvania
• Permetrin
• Elon Musk
• Spesies kunci
• USS Suwannee (CVE-27)
• Philadelphia Union
• EMD AEM-7
• Bisoro
• Simon Louvish
• Penambangan batu bara
• Keystone B-3
• Keystone B-4
• Keystone B-5
• Keystone B-6
• Keystone Aircraft
• B3
• Keystone Pipeline
• List of United States bomber aircraft
• Douglas Y1B-7
• Keystone LB-6