Curtiss XP-31 Swift

American fighter prototype

XP-31 Swift

Curtiss XP-31 with Vee engine
Role	Experimental monoplane fighter Type of aircraft
Manufacturer	Curtiss
First flight	July 1932^[1]
Introduction	1933
Primary user	United States Army Air Corps
Number built	1

The Curtiss XP-31 Swift (Wright Field Project Number XP-934) was a 1930s American experimental monoplane fighter built by Curtiss for the United States Army Air Corps.

The XP-31 featured the first enclosed cockpit on a U.S. pursuit aircraft and was also the last pursuit aircraft to have fixed landing gear and externally braced wings. Despite its innovations, the XP-31 did not offer any advantages compared to its rival the Boeing P-26 Peashooter and was not ordered into series production.

Design and development

Curtiss offered the XP-31 (given the Wright Field Project Number XP-934) in a 1932 competition with the P-26. It was a low-wing monoplane with fixed landing gear, first flown in July. It was the AAC's first single-seat closed-cockpit fighter, and the last with fixed gear and wing struts. Despite its small size, it was badly overweight, and carried 125 gallons (104 imp gal, 474 L) of fuel. Although Curtiss considered the design significant in that it introduced various new technologies, compared to its contemporaries the XP-31 was already outmoded, and, more importantly, testing showed that it fell below performance expectations.^[2]

Testing and evaluation

Powered by a 700 hp (520 kW) R-1750 Cyclone radial, its performance was dismal, despite retractable leading edge slots and large trailing-edge flaps, so a 600 hp (450 kW) Curtiss V-1570 Conqueror was substituted. In this form, the Curtiss XP-31 Swift (s/n 33-178) was delivered on 1 March 1933, having already lost to the P-26. The sole example was scrapped in 1935.^[2]

Operators

United States

United States Army Air Corps

Specifications

Data from U.S. Fighters: Army-Air Force 1925 to 1980s^[3] and Fighters of the United States Air Force^[2]

General characteristics

Crew: one pilot
Length: 26 ft 3 in (8.0 m)
Wingspan: 36 ft 0 in (11 m)
Height: 7 ft 9 in (2.4 m)
Wing area: 203 sq ft (18.86 m²)
Empty weight: 3,334 lb (1,512 kg)
Gross weight: 4,143 lb (1,879 kg)
Powerplant: 1 × Curtiss V-1570 Conqueror water-cooled 12-cylinder vee engine , 600 hp (450 kW)

Performance

Maximum speed: 208 mph (335 km/h, 181 kn)
Range: 370 mi (595 km, 320 nmi)
Service ceiling: 24,400 ft (7,437 m)

Armament

2 × fixed, forward-firing .30 in (7.62 mm) M1919 Browning machine guns in cowl
2 × fixed, forward-firing .30 in (7.62 mm) M1919 Browning machine guns in cheeks

Aircraft of comparable role, configuration, and era

Boeing P-26 Peashooter

Related lists

List of military aircraft of the United States

References

Notes

^ Green and Swanborough 1994, p. 131.
^ ^a ^b ^c Dorr and Donald 1990, p. 60.
^ Jones 1975, p. 81.

Bibliography

Bowers, Peter M. Curtiss Aircraft 1907-1947. London: Putnam & Company Ltd., 1979. ISBN 0-370-10029-8.
Donald, David, ed. Encyclopedia of World Aircraft. Etobicoke, Ontario, Canada: Prospero Books, 1997. ISBN 1-85605-375-X.
Dorr, Robert F. and David Donald. Fighters of the United States Air Force. London: Aerospace Publishing, 1990. ISBN 0-600-55094-X.
Green, William and Gordon Swanborough. The Complete Book of Fighters. New York: Smithmark, 1994. ISBN 0-8317-3939-8.
Jones, Lloyd S. U.S. Fighters: Army-Air Force 1925 to 1980s. Fallbrook, California: Aero Publishers, 1975. ISBN 0-8168-9200-8.
Pedigree of Champions: Boeing Since 1916, Third Edition. Seattle, Washington: The Boeing Company, 1969.

External links

Media related to Curtiss XP-31 at Wikimedia Commons

Curtiss and Curtiss-Wright aircraft

Manufacturer
designations

Early types	Golden Flier Reims Racer Beachey Special
Model letters	C D E F FL GS H HA HS J JN -5 -6H K L MF N NC O R S T
Model numbers	1 B F 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 K/P 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 A B 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 I P S 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100
"L" series	L-17 L-18 L-19 L-22 L-41 L-44 L-72 L-79 L-85 L-115 L-117 L-710
"CA" series	CA-1
"CR" series	CR-1 CR-2
"CW" series	CW-1 CW-2 CW-3 CW-4 CW-5 CW-6 CW-8 CW-9 CW-10 CW-11 CW-12 CW-14 CW-15 CW-16 CW-17 CW-18² CW-19 CW-20 CW-21 CW-22 CW-23 CW-24 CW-25 CW-26 CW-27 CW-28 CW-29 CW-32 CW-33 CW-40
"P" series	P-200 P-202 P-212 P-218 P-219 P-222 P-223 P-224 P-225 P-227 P-228 P-229 P-232 P-235 P-238 P-239 P-240 P-241 P-243 P-244 P-245 P-247 P-248 P-249 P-250 P-251 P-252 P-253 P-254 P-255 P-256 P-257 P-259 P-261 P-264 P-268 P-269 P-272 P-273 P-274 P-275 P-276 P-277 P-278 P-279 P-280 P-282 P-283 P-291 P-292 P-293 P-295 P-296 P-297 P-298 P-299 P-302 P-303 P-304 P-305 P-306 P-307 P-509 P-517 P-518 P-538 P-539 P-541 P-545 P-551 P-558 P-565 P-586 P-588 P-592
"X" series	X-100 X-200 X-300 X-410 X-425

Operator and role

Civil

Experimental	No. 1 Model C SX-5-1 Tanager
Racers and record	No. 2 Cox Racer CW-B-14R
Airliners	Eagle Condor 18 Condor II Kingbird Thrush Commando
Utility	Model D Model E Model F Carrier Pigeon Falcon Robin Lark 6B CW-12 CW-14 Sportsman CW-15 Sedan CW-16 CW-19W

Army

Ground attack	A-3 A-4 A-5 A-6 A-8 YA-10 A-12 YA-14 A-18 A-25 A-40 XA-43
Bombers	NBS-1 B-2 XNBS-4
Transports	XC-10 C-30 Condor C-46 Commando C-55 Commando C-76 C-113 Commando
Fighters	S 18 PN-1 PW-8 P-1 to P-5 P-6 XP-10 P-11 P-14² P-17 XP-18² XP-19² YP-20 XP-21 XP-22 XP-23 XP-31 P-36 YP-37 P-40 XP-42 XP-46 XP-53 XP-55 YP-60 XP-62 XP-71 XP-87
Observation	O-1 O-11 O-12 O-13 O-16 O-18 O-24² O-26 XO-30² O-39 O-40 O-52
Racers	R-6 R-8
Trainers	J L JN Fledgling AT-4 Hawk AT-5 Hawk BT-4 AT-9 Jeep
Experimental	X-19
Licensed	USAO-1 NBS-1/Model 30

Navy

Bombers	CT BFC BF2C SBC SB2C XSB3C² XBTC XBT2C
Fighters	HA GS TS-1 FC F2C F3C F4C F5C¹ F6C F7C F8C F9C F10C F11C XF12C F13C XF14C XF15C
Observation/scout	CS/SC S2C XS3C S4C SC OC O2C O3C SOC SO2C SO3C
Trainers	N-9 N2C SNC
Transports	RC R4C R5C
Maritime patrol	H-16 F5L HS-1L & HS-2L
Racers and record	NC CR R2C R3C

Export

Bombers	Canada CW-14 Osprey
Maritime patrol	H-2, H-4, H-8 and H-16 F5L HS-2L
Fighters	CW-17 Pursuit Osprey² CW-21 Demon
Trainers	Canuck CW-14 Osprey CW-16 CW-18² CW-22

¹ Designation skipped ² Not built

USAAS/USAAC/USAAF/USAF fighter designations 1924–1962, and Tri-Service post-1962 systems

1924 sequences
(1924–1962)

Pursuit (1924–1948)	P-1 P-2 P-3 P-4³ Curtiss P-4 Boeing P-4 P-5 P-6 P-7 P-8 P-9 P-10 P-11 P-12 P-13 P-14 P-15 P-16 P-17 P-18 P-19 P-20 P-21 P-22 P-23 P-24 P-25 P-26 P-27 P-28 P-29 P-30 P-31 P-32 P-33 P-34 P-35 P-36 P-37 P-38 P-39 P-39E P-40 P-41 P-42 P-43 P-44 P-45 P-46 P-47 P-48 P-49 P-50 P-51 P-52 P-53 P-54 P-55 P-56 P-57 P-58 P-59³ XP-59 P-59 P-60 P-61 P-62 P-63 P-64 P-65 P-66 P-67 P-68 P-69 P-70 P-71 P-72 P-73² P-74¹ P-75 P-76 P-77 P-78 P-79 P-80 P-81 P-82 P-83 P-84 P-85 P-86 P-87 P-88 P-89 P-90 P-91 P-92
Fighter (1948–1962)	F-38 F-39 F-40 F-47 F-51 F-59 F-61 RF-61C F-63 F-80 F-81 F-82 F-83 F-84 F-84F/J F-84H F-85 F-86 F-86C F-86D/G/K/L F-87 F-88 F-89 F-90 F-91 F-92 F-93 F-94 F-95 F-96 F-97 F-98 F-99 F-100 F-100B F-101 F-102 F-102B F-103 F-104 XF-104 F-104S NF-104A F-105 F-106³ XF-106 F-106 F-107 F-108 F-109² F-110 F-111 F-111B F-111C F-111K AFTI/F-111A EF-111A
Pursuit, Biplace	PB-1 PB-2 PB-3
Fighter, Multiplace	FM-1 FM-2
Non-sequential	F-24 P-322 P-400

Tri-service sequence
(1962–present)

Main sequence	F-1 F-1C/D F-1E/F F-2 F-3 F-4 F-4K/M F-5 G F-6 F-7 F-8 F-9 F-9F–J F-10 F-11 F-12 F-12C² F-13¹ F-14 F-15 F-15E F-15EX F-15J F-15 STOL/MTD F-16 F-16XL NF-16D F-17 F/A-18 F/A-18E/F EA-18G F-19¹ F-20 F-21 F-22 YF-22 FB-22 F-23
Non-sequential	F-35 F-35I X-35 F-117

Covert designations

Related designations

FV-12

¹ Not assigned • ² Unofficial • ³ Assigned to multiple types
See also: "F-19" • 1919-1924 sequence

v t e Wright Field project numbers (1930–1934)
XP-900 XB-901 XP-902 XP-903 XP-904 905¹ XB-906 XB-907 XB-908 XC-909 XC-910 XO-911 XPT-912 XPT-913 XPT-914 XPT-915 916¹ XB-917 XC-918 919¹ XC-920 XB-921 922¹ XP-923 XO-924 XP-925 XO-926 XP-927 XC-928 XP-929 XPT-930 XPT-931 XO-932 XPT-933 XP-934 XBT-935 XP-936 XBT-937 XP-938 XO-939 XP-940 XC-941 XC-942 XPT-943 XP-944 XPT-945 946¹ 947¹ XP-948 949¹ XB-950
¹ Not assigned

Wright Field project numbers (1930–1934)