This is a list of representative R-2800 variants, describing some of the mechanical changes made during development of the Double Wasp. Power ratings quoted are usually maximum "military" power that the engine could generate on takeoff and at altitude; 100 Octane fuel was used, unless otherwise noted. The R-2800 was developed and modified into a basic sequence of subtypes, "A" through "E" series, each of which indicated major internal and external modifications and improvements, such that the "E" series engines had very few parts in common with the "A".. Pratt & Whitney's internal variant identification incorporated the series letter as part of the designation, for example Double Wasp S1A4-G ("A" series) and Double Wasp CB17 ("C" series). ;Note:Suffixes such as
-S14A-G denote engines developed for export to other countries.
Data from White (Airlife) unless otherwise noted: Military The dash number for each military type (e.g.:
-21) was allocated to identify the complete engine model in accordance with the specification under which the engine was manufactured. Thus dash numbers did not necessarily indicate the sequence in which the engines were manufactured. For example: the -18W was a "C" series engine, built from 1945, whereas the -21 was a "B" series engine, built from 1943. Until 1940 the armed forces adhered strictly to the convention that engines built for the Army Air Forces used engine model numbers with odd numeric suffixes (e.g.: -5), while those built for the US Navy used even (e.g.: -8). After 1940, however, in the interests of standardization, engines were sometimes built to a joint Army-Navy contract, in which case the engines used a common numeric suffix (e.g. the -10 was used by both Army and Navy aircraft.) The suffix
W e.g.:
-10W denotes a sub-series modified to use
water injection. The "Anti-Detonant Injection" (ADI) system injected a mixture of water and
methanol into the carburetor to increase power for short periods. Several models of the R-2800s were fitted with ADI as standard equipment and were not given the
W suffix. Few commercial aircraft used water injection.
"A" Series: •
R-2800-1 : at 2,400 rpm at . Production prototype of "A" series engines with the first flight test July 29, 1939. Single-speed two-stage supercharger. Production = 2 (P&W). Tested in
Vultee YA-19B. •
R-2800-5 : at 2,600 rpm at . Main production "A" series engine used in
Martin B-26A, early B series and XB-26D and
Curtiss C-55/XC-46. Production = 1,429 (P&W 475, Ford 954.) •
R-2800-39 - •
Double Wasp S1A4-G -
"B" Series: fitted to some R-2800 subtypes. •
R-2800-8 : at 2,700 rpm at ; at 2,700 rpm at . First series production "B" Series engine using a two-stage, two-speed supercharger and with internal engineering changes resulting in increased power and reliability. Updraft
Bendix-Stromberg PT-13D-4 pressure carburetor. First production engines delivered to
USN November 11, 1941. Used in
Brewster F3A-1, Goodyear FG-1, Vought F4U-1 and F4U-2. Production = 3,903 (P&W 2,194; Nash 1,709.) •
R-2800-8W :
WEP with water injection. First production engine using ADI equipment, major production version of -8 and used in some versions of F4U Corsair. Production = 8,668 (P&W 5,574; Nash 3,094.) •
R-2800-10 and
R-2800-10W : at 2,700 rpm at ; at 2,700 rpm at ; up to WEP with water injection. Similar to -8 series apart from downdraft PT-13G2-10 and PT-13G6-10 (-10W) carburetor. Used in
Curtiss XP-60E,
Grumman F6F-3 (-10; late production -10W) and F6F-5 (-10W) series and
Northrop XP-61, YP-61, and P-61A-1. Production = 4,621 -10 (P&W 2,931; Nash 1,690) and 12,940 -10W (P&W 3,040; Nash 9,900); Total = 17,561. •
R-2800-21 : at 2,700 rpm at ; at 2,700 rpm at . First production variant fed by a
General Electric C-1
turbosupercharger. Designed for use in the
Republic P-47B, C, D, G and XP-47F and K. Production = 5,720 (P&W 1,049; Ford 4,671.) •
R-2800-25 - — for
Northrop P-61 Black Widow •
R-2800-27 - •
R-2800-31 - •
R-2800-41 - •
R-2800-43 - •
R-2800-51 - •
R-2800-59 : at 2,700 rpm at ; at 2,500 rpm at ; WEP with water injection. Main production variant used in P-47 series, fed by an improved C-23 turbosupercharger. Differed from -21 in being fitted with ADI and a General Electric ignition system with a simplified tubular ignition harness developed by the Scintilla company in partnership with Bendix. Used in P-47C and D, XP-47L. Production = 11,391 (P&W 592; Ford 10,799). •
R-2800-59W - •
R-2800-65 - •
R-2800-65W - •
R-2800-71 - •
R-2800-75 - •
R-2800-79 - •
Double Wasp 2SB-G -
"C" Series •
R-2800-18W : at 2,800 rpm at ; at 2,800 rpm at . First series production variant of the "C" Series, which was a complete redesign of the R-2800. Some of the main changes were:
forged rather than
cast cylinders, allowing an increased compression ratio (from 6.65:1 to 6.75:1); a redesigned crankshaft; a single piece (rather than split) crankcase center section; a two section nose casing, incorporating hydraulically operated
torque-monitoring equipment and an automatic vacuum-operated
spark-advance unit. The supercharger used
fluid coupling for the second stage. Updraft Bendix-Stromberg PT-13G2-10 carburetor. Used in
Vought F4U-4 and variants of the -4. Production = 3,257 (P&W). •
R-2800-22W - •
R-2800-34 - •
R-2800-34W - , with water-methanol injection •
R-2800-44 - •
R-2800-44W - •
R-2800-48 - •
R-2800-48W - •
R-2800-52W - •
R-2800-54 - •
R-2800-57 - •
R-2800-57C - •
R-2800-73 - — with General Electric CH-5-A3 turbocharger for P-61C Black Widow •
R-2800-77 - •
R-2800-83 - •
R-2800-83AM - •
R-2800-99W - •
R-2800-103W - •
Double Wasp CB16 - , •
Double Wasp CB17 - •
Double Wasp S1C3-G -
"D" Series: •
R-2800-23 - •
R-2800-29 -
"E" Series: •
R-2800-30W - , with water-methanol injection — with variable speed single-stage supercharger for
Grumman F8F-2 Bearcat •
R-2800-32W - , with water-methanol injection — with variable speed two-stage supercharger for
Vought F4U-5 Corsair ==Applications==