It had been originally planned for all 25 planes of the add-on order for P-26s to be completed as P-26Bs. Unfortunately, there were delays in the production of the Pratt and Whitney fuel-injected Wasp engines. Consequently, twenty-three of the 25 aircraft added to the original order for 111 P-26As were built as P-26Cs with the carbureted R-1340-27 engine. These engines differed from those in the P-26A only in slight differences in the fuel and carburetion systems. The differences from the P-26A were so slight that the factory model number (Model 266) was not changed. Serials were 33-181, 33-183/203. The first P-26C was delivered on February 10, 1936, and the last on March 7, 1937.
After about a year in service, all but six of the 23 P-26Cs were converted to P26B standards (Boeing 266A) by the installation of fuel injection engines and revision of the fuel system and its controls. These planes were then redesignated P-26B, a rare occasion of an aircraft reverting to an earlier designation.
Serials of P-26C: 33-181, 33-183/203
Specification of Boeing P-26C:
One Pratt and Whitney SR-1340-33 Wasp nine-cylinder supercharged air-cooled radial engine with fuel injection rated at 600 hp at 7500 feet. Performance: Maximum speed 235 mph. Range 635 miles. initial climb rate 2360 ft/min. Service ceiling 27,000 feet, absolute ceiling 28,300 feet. Weights: 2332 lbs empty, 3075 lb gross. Dimensions: Wingspan 27 feet 11.6 inches, length 23 feet 9 inches, height 10 feet 0.38 inches, wing area 149.5 square feet. Armament: One 0.50-in, one 0.30-in machine guns, or two 0.30-in machine guns mounted in the fuselage sides firing through the engine cylinder banks. Racks were provided under the fuselage for five 30-lb bombs or two 100-lb bombs.
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