The designation P-40R was assigned to P-40F and P-40L airframes that had their Packard Merlin engines replaced in service
with Allison V-1710-81 engines. Converted P-40Fs were redesignated P-40R-1, converted P-40Ls as P-40R-2. These planes were
used exclusively for training duties. US Army documents claim that over 600 such conversions were made, but only
70 P-40F and 53 P-40L conversions can be confirmed:
41-13600/13695 Curtiss P-40F Warhawk 13600,13615,13640,13641,13651,13659,13662,13663,13666, 13682,13691 converted to P-40R-1 41-13697/14299 Curtiss P-40F Warhawk 13715,13722,13747,13794,13818,13822,13825,13830,13834, 13842,13853,13916,13976,13977,13982,13992,14046, 14051,14071,14078,14124,14129,14132,14150,14167, 14168,14189,14190,14256,14268,14293 converted to P-40R-1 41-14300/14422 Curtiss P-40F-5-CU Warhawk 14304,14332/14335,14382,14383,14387,14420 converted to P-40R-1 41-14423/14599 Curtiss P-40F-10-CU Warhawk 14497,14499,14500,14561 converted to P-40R-1. 42-10480/10699 Curtiss P-40L-5-CU Warhawk 10513, 10616, 10642, 10648, 10669, 10676 converted to P-40R-2 42-10700/10847 Curtiss P-40L-10-CU Warhawk 10712 converted to P-40R-2. 42-10848/10959 Curtiss P-40L-15-CU Warhawk 10864, 10873, 10874, 10883, 10903, 10913, 10924, 10944, 10953, 10954 converted to P-40R-2 42-10960/11129 Curtiss P-40L-20-CU Warhawk 10964, 10974, 10983, 10991, 10992, 11010, 11026, 11037, 11039, 11053, 11055, 11058, 11069, 11064, 11065, 11068/11070, 11075, 11076, 11078, 11080, 11083, 11085, 11090/11092, 11105, 11109, 11110, 11112/11116, 11120 converted to P-40R-2
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