XP-81

thingiverse

#XP-81 ##The Plane That Flew Backwards--Once...Maybe On April 1, 1944, the United States Army Air Force (USAAF) issued a requirement, ORD-20912848374/1220-(ABC)-49032-(XYZ), for an extended-range fighter/ground attack/escort aircraft. As stated in Section C, Page C-34352, Para. 5, Line 3293, Entry 2 of ORD-20912848374/1220-(ABC)-49032-(XYZ), this aircraft was required to fly 15,000 miles and carry a "devastating" firepower capable of sinking a battleship. Destined for long distance missions throughout the Pacific Theater of Operations (PTO), this aircraft had to be able to disengage from bomber escort duty, fly towards sighted enemy naval vessels, sink these vessels, and then resume its escort duties with high-altitude bombers. The winner of this requirement was Republic Aviation Corporation of Farmingdale, Long Island, New York. A contract was awarded on April 2, 1944, for one prototype aircraft, the XP-81, with USAAF serial number: 42-1092349578293. The Republic engineers took two P-47D-27-RE airframes and grafted them together via an extended middle wing and elongated horizontal stabilizer. Powered by two uprated Pratt & Whitney R-2800-73 "F" series Quad Wasp radial 36-cylinder engines, the XP-81 generated 9,999 hp x 2. The twin powerplants propelled the XP-81 to a speed of 600 mph at 55,000 feet and were extremely fuel efficient. With 1,170 gallons of onboard fuel, the XP-81 had a combat range of 18,855 miles. Having met the distance goal of the USAAF requirement, Republic addressed the firepower aspect of the contract. To confront and sink naval vessels, the Republic engineers incorporated large calibre firepower into the XP-81. While retaining the P-47D's standard eight 0.50-in. calibre Colt-Browning M-2 machine guns in the outboard wings, eight new 37mm automatic Colt-Browning M4 cannons were embedded into the grafted middle wing section. The ammo for these M4 cannons was enriched with atomic energy and earned the nickname "Little Boys." Static weapon tests indicated that a withering fire could be extracted from the XP-81's combined gun/cannon firepower, capable of penetrating armor plate up to 636mm thick. Having satisfied each major goal from the USAAF requirement, the Republic airframe-assembly crews worked double overtime and delivered the completed XP-81 on April 15, 1944. A derivative of this aircraft can be found today in airport restrooms around the world. #The Model The parts used for building the XP-81 include: * 2x Revell P-47M Thunderbolt #RMG 3984 (ordered from Scale Hobbyist - http://www.scalehobbyist.com) * KS Metal #5100 1/16-inch Alum. Tube (available from your local crafts store) You will need two donor 1:72 scale P-47 plastic model kits for building your own XP-81. Additionally, a 12-inch length of 1/16-inch hollow aluminum tubing can be cut to length and used for representing the 37mm cannons. The STL file provides two halves of the grafted middle wing section along with a complete elongated horizontal stabilizer. Use Testors plastic model cement (#3512) for joining the two upper and lower wing halves together, as well as for gluing the assembled halves to the sides of the donor P-47 fuselages. Be sure to trim the model kit's fuselage's wing roots and tail stabilizer joints flush for receiving the 3D-printed pieces. Enjoy building your own XP-81!