includes prototype, pre-production, and operational types. Prototypes are normally prefixed with "X" and often unnamed (note that these are not the same as the experimental X-planes, which are never expected to go into production), while pre-production models are usually prefixed "Y".
Pursuit
Pursuit Aircraft of the US Army Air Service/Corps/Force, 1918-1948.
After formation of US Air Force (USAF), all "P" designations were changed to "F" while retaining number.
Initially, "PW" was used to indicate "Pursuit, Water-cooled engine".
List in numerical order of designations:
- PW-8 - Curtiss
- PW-9 - Boeing, FB in navy
- P-1 Hawk - Curtiss, derived from PW-8; US Navy designation was F6C
- P-2 Hawk - Curtiss
- P-3 Hawk - Curtiss
- P-4 - Boeing
- P-5 Superhawk - Curtiss
- P-6 Hawk - Curtiss, derived from P-1
- XP-7 - Boeing
- XP-8 - Boeing
- XP-9 - Boeing
- XP-10 - Curtiss
- P-11 Hawk - Curtiss
- P-12 - Boeing, F4B in Navy
- XP-13
- XP-14 - Curtiss
- XP-15 - Boeing
- P-16 - Berliner-Joyce, F2J to Navy
- XP-17 - Curtiss
- XP-18 - Curtiss
- XP-19 - Curtiss
- YP-20 - Curtiss, derived from P-6
- XP-21 - Curtiss
- XP-22 - derived from P-6
- XP-23 - Curtiss
- YP-24 - Lockheed
- Y1P-25 - Consolidated
- P-26 - Boeing "Peashooter" monoplane
- XP-27 - Consolidated
- XP-28 - Consolidated
- F7B - Boeing, modified F7B
- P-30 - Consolidated, aka PB-2A
- XP-31 - Curtiss
- XP-32 - Boeing
- XP-33 - Consolidated
- XP-34 - Wedell-Williams
- P-35 - Seversky
- P-36 - Curtiss Model 75A, radial engine
- YP-37 - Curtiss Model 75I, in-line engine
- P-38 Lightning - Lockheed, twin-engine twin-boom
- P-39 Airacobra - Bell, engine mounted behind pilot
- P-40 - Curtiss, Tomahawk (P-40A to P-40C), Kittyhawk (P-40D to P-40M), Warhawk (P-40N to P-40Q)
- XP-41 - Seversky, derived from Seversky P-35
- XP-42 - Curtiss P-36 with experimental engine cowlings
- P-43 Lancer - Republic, derived from XP-41
- P-44 Rocket - cancelled
- P-45 designation changed to P-39C
- XP-46 - Curtiss
- P-47 Thunderbolt - Republic
- XP-48 - Douglas
- XP-49 - Lockheed, derived from P-38
- XP-50 - Grumman, derived from US Navy XF5F
- P-51 Mustang - North American, originally for export to Britain
- XP-52 - Bell, twin-boom pusher configuration, never built
- XP-53 - Curtiss P-40 with laminar-flow wing, cancelled during construction
- XP-54 - Vultee, twin-boom pusher configuration
- XP-55 Ascender - Curtiss, flying-wing configuration with pusher engine
- XP-56 - Northrop, tail-less with pusher engine, magnesium construction
- XP-57 - Tucker, cancelled before construction
- XP-58 - Lockheed, another twin-engine, twin-boom
- P-59 Airacomet - Bell, 1st American aircraft powered by jet engine
- YP-60 - Curtiss
- P-61 Black Widow - Northrop
- XP-62 - Curtiss
- P-63 Kingcobra - Bell, engine again mounted behind pilot
- P-64 - North American, intended for export, but used by USAAF as fighter trainer
- XP-65 - Grumman, derived from XP-50
- P-66 Vanguard - Vultee, intended for export, but used by USAAF as fighter trainer
- XP-67 - McDonnell
- XP-68 - Vultee
- XP-69 - Republic
- P-70 Havoc - Douglas, "Havoc" night-fighter derived from A-20
- XP-71 - Curtiss
- XP-72 - Republic
- XP-73 - mysterious Hughes project
- P-74 skipped
- P-75 Eagle - Fisher division of General Motors
- XP-76 - Bell
- XP-77 - Bell, lightweight fighter of wooden construction
- XP-78 - North American, changed to XP-51B during construction
- XP-79, Northrop
- P-80/F-80 Shooting Star - Lockheed, turbo-jet engine
- XP-81 - Convair, turbo-prop + turbo-jet engines
- P-82/F-82 Twin Mustang - North American
- XP-83 - Bell, two jet engines