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Consolidated P-30

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P-30 (PB-2)
Consolidated P-30
General information
TypeFighter aircraft
National originUnited States
ManufacturerConsolidated Aircraft
StatusRetired
Primary userUnited States Army Air Corps
Number built60
History
First flightJanuary 1934

The Consolidated P-30 (PB-2) was a 1930s United States two-seat fighter aircraft. An attack version called the A-11 was also built, along with 2 Y1P-25 prototypes and YP-27, Y1P-28, and XP-33 proposals. The P-30 is significant for being the first fighter in United States Army Air Corps service to have retractable landing gear, an enclosed and heated cockpit for the pilot, and an exhaust-driven turbo-supercharger for altitude operation.[citation needed]

Design and development

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In 1931, the Detroit Aircraft Corporation, parent company of the Lockheed Aircraft Company, built a two-seat single-engined fighter aircraft based on the Lockheed Altair high-speed transport as a private venture. The prototype, the Detroit-Lockheed XP-900, flew in September 1931 and was purchased by the United States Army Air Corps as the Lockheed YP-24. It had impressive performance, being faster than any fighter then in service with the Air Corps, and an order for five Y1P-24 fighters and four Y1A-9 attack aircraft was placed for the new aircraft, despite the loss of the prototype on 19 October 1931.[1][2] The Detroit Aircraft Corporation went into bankruptcy eight days later, however, leading to the cancellation of the contract.[1][3]

When the Detroit Aircraft Corporation failed, the chief designer of the YP-24, Robert J. Woods was hired by Consolidated Aircraft.[3] Woods continued to develop the YP-24, the design becoming the Consolidated Model 25, with all-metal wings replacing the wooden wings of the YP-24 and with a larger tail. The Army Air Corps ordered two prototypes as the Y1P-25 in March 1932, to be powered by a Curtiss V-1570-27, fitted with a turbo-supercharger on the port side of the forward fuselage. The order for the second prototype was quickly changed to a Y1A-11 attack aircraft, omitting the supercharger.[4][5]

First to fly was the Y1P-25, which was delivered to the Air Corps on 9 December 1932. It demonstrated promising performance, reaching a speed of 247 miles per hour (398 km/h) at 15,000 feet (4,600 m), but was destroyed in a crash on 13 January 1933, killing its pilot, Capt. Hugh M. Elmendorf (whose name was later given to Elmendorf Air Base in Alaska).[4][6]

The Y1A-11, armed with four forward-firing machine guns instead of the two of the Y1P-25 and racks for 400 lb (180 kg) of bombs, was delivered to Wright Field on 5 January 1933. On 20 January 1933, the Y1A-11 disintegrated in midair, killing pilot Lt. Irvin A. Woodring.[7] Despite the loss of both prototypes in a week, on 1 March 1933, the Air Corps placed an order for four P-30 fighters and four A-11 attack aircraft. These production variants differed from the prototypes in having stronger fuselages, simplified undercarriages and more powerful engines.[3][8]

Operational history

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The first P-30 was delivered in January 1934.[8] Testing showed that the gunner's cockpit was uncomfortable and cold at the high altitudes where the P-30 was intended to fight, while the rearward-facing gunners were liable to black out when the aircraft was maneuvered.[9] Despite these concerns, on 6 December 1934, the U.S. Air Corps placed an order for a further 50 P-30As, with more powerful V-1570-61 engines driving a three-bladed variable-pitch propeller and with oxygen supplies for the crew.[10][11]

Three of the four P-30s were delivered to the 94th Pursuit Squadron at Selfridge Field in 1934. The first P-30A, by this time redesignated PB-2A (pursuit, biplace), made its maiden flight on 17 December 1935, with deliveries to service units starting on 28 April 1936. The last of the 50 PB-2As were completed by August that year.[11]

While intended as a high altitude fighter, the PB-2 flew relatively few high-altitude flights, partly because of the discomfort for the crew. One exception took place in March 1937, when a PB-2A was flown to 39,300 feet (12,000 m) before being forced to return to lower altitudes when the aircraft's controls froze.[12] On 17 October 1936, a PB-2A flown by Lt. John M. Sterling won the Mitchell Trophy air race with a speed of 217.5 miles per hour (350.0 km/h).[13] Since the PB-2A was one of the few aircraft at the time to have retractable landing gear, they were frequently damaged in "wheels-up" landings when the pilots forgot to extend the landing gear.[14]

One PB-2A was modified to a single-seat configuration as the PB-2A Special, to compete in a 1936 Air Corps competition for a new fighter to replace the Boeing P-26 Peashooter. It was larger and heavier than the other competitors and was much more expensive.[citation needed] It crashed during testing, with the Seversky P-35 being ordered into production.[15][16] One A-11 was converted to the XA-11A testbed with the new 1,000 hp (750 kW) Allison XV-1710-7 engine.[13]

While the PB-2 was sturdy,[14] the two-seat fighter concept was obsolete by the time the aircraft entered service,[13] and by 1939, all had been replaced in front-line service by Seversky P-35 and Curtiss P-36 Hawk aircraft. The survivors remained in use as training aircraft until after the start of World War II, with the last being withdrawn from use on 2 June 1942.[17]

Variants

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Y1P-25
Further development of Lockheed YP-24 with all-metal wing, 600 hp (450 kW) Curtiss V-1570-27 Conqueror turbo-supercharged engine. Two fixed forward firing .30 in machine guns and one flexibly mounted gun in rear cockpit. One built.[6]
Y1A-11
Ground-attack version of Y1P-25. Powered by unsupercharged engine and armament of 4 forward-firing .30 in guns in nose, one in rear cockpit and up to 400 lb (180 kg) of bombs. One built.[3][7]
YP-27
Proposed variant of Y1P-25 with a 550 hp (410 kW) Pratt & Whitney R-1340-21G Wasp radial engine. Unbuilt.[18]
Y1P-28
Proposed variant of Y1P-25 with a 600 hp (450 kW) R-1340-19 Wasp; unbuilt.[18]
P-30
Initial production batch for Army Air Corps. 675 hp (503 kW) Curtiss V-1570-57 turbo-supercharged engine. Four built, later redesignated PB-2.[3][15]
The last of the four Consolidated A-11s
A-11
Initial production ground-attack aircraft, with unsupercharged V-1570-59 engine. Four built.[3]
P-30A
Main production fighter powered by a 700 hp (520 kW) turbo-supercharged Curtiss V-1570-61 engine; 50 built, redesignated PB-2A.[15]
The PB-2A Special
PB-2A Special
Seventh PB-2A modified to single-seat configuration. Crashed during flight testing.
XP-33
Proposed version with a 800 hp (600 kW) Pratt & Whitney R-1830-1 Twin Wasp engine; unbuilt.[15]
XA-11A
Conversion of A-11 as testbed for 1,000 hp (750 kW) Allison XV-1710-7. One converted by Bell Aircraft, who referred to it as their Model 2.[13]

Specifications (PB-2A)

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Data from Singular Two-Seater[11]

General characteristics

  • Crew: two
  • Length: 30 ft 0 in (9.14 m)
  • Wingspan: 43 ft 11 in (13.38 m)
  • Height: 8 ft 3 in (2.51 m)
  • Wing area: 297 sq ft (27.6 m2)
  • Empty weight: 4,306 lb (1,950 kg)
  • Gross weight: 5,623 lb (2,556 kg)
  • Powerplant: 1 × Curtiss V-1570-61 Conqueror liquid-cooled V12 engine, 700 hp (520 kW)

Performance

  • Maximum speed: 275 mph (443 km/h, 239 kn) at 25,000 ft (7,600 m)[15]
  • Cruise speed: 215 mph (346 km/h, 187 kn) at 15,000 ft (4,600 m)
  • Range: 508 mi (818 km, 442 nmi)
  • Service ceiling: 28,000 ft (8,530 m)
  • Climb to 15,000 ft (4,600 m): 7 min 48 s

Armament

  • Guns:
    • 2 × 0.30 in (7.62 mm) machine guns firing through the propeller
    • 1 × 0.30 in (7.62 mm) machine gun in the rear cockpit
  • Bombs: 170 lb (77 kg) bombs

See also

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Related development

Aircraft of comparable role, configuration, and era

Related lists

Notes

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  1. ^ a b Francillon 1982, pp. 114–115.
  2. ^ Angelucci and Bowers 1987, p. 262.
  3. ^ a b c d e f Wegg 1990, p. 68.
  4. ^ a b Pelletier 2000, p. 2.
  5. ^ Angelucci and Bowers 1987, pp. 95–96.
  6. ^ a b Dorr and Donald 1990, p. 51.
  7. ^ a b Pelletier 2002, pp. 2–3.
  8. ^ a b Pelletier 2002, p. 3.
  9. ^ Dorr and Donald 1990, p. 57.
  10. ^ Wegg 1990, pp. 68–69.
  11. ^ a b c Pelletier 2000, p. 5
  12. ^ Pelletier 2002, p. 10.
  13. ^ a b c d Wegg 1990, p. 69.
  14. ^ a b Pelletier 2002, p. 9.
  15. ^ a b c d e Angelucci and Bowers 1987, p. 97.
  16. ^ Green and Swanborough 1979, p. 11.
  17. ^ Pelletier 2002, p. 11.
  18. ^ a b Angelucci and Bowers 1987, p. 96.

Bibliography

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  • Angelucci, Enzo. and Peter M. Bowers. The American Fighter. New York: Orion Books, 1987. ISBN 0-517-56588-9.
  • Dorr, Robert F. and David Donald. Fighters of the United States Air Force. London: Temple Press/Aerospace, 1990. ISBN 0-600-55094-X
  • Francillon, René J. Lockheed Aircraft since 1913. London: Putnam, 1982. ISBN 0-370-30329-6.
  • Green, William and Gordon Swanborough. "The end of the beginning ... The Seversky P-35". Air Enthusiast Ten, July–September 1979, pp. 8–21.
  • Pelletier, Alain J. "Singular Two-Seater: Consolidated's PB-2A – The USAAC's Only Two-Seat Fighter". Air Enthusiast No. 85, January/February 2000, pp. 2–11. ISSN 0143-5450.
  • Swanborough, Gordon and Peter M. Bowers. United States Military Aircraft Since 1909. Washington, D.C.: Smithsonian, 1989. ISBN 0-87474-880-1.
  • Wegg, John. General Dynamics Aircraft and their Predecessors. London: Putnam, 1990. ISBN 0-85177-833-X.
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