▁ 1 9 4 1 ; ▁modified ▁to ▁XP - 6 0 D . ▁XP - 6 0 A ▁Curt iss ▁Model ▁ 9 5 A ; ▁All ison ▁V - 1 7 1 0 - 7 5 ▁engine ▁with ▁B - 1 4 ▁tur bos uper char ger ; ▁arm ament : ▁six ▁. 5 0 - cal ▁M G . ▁One ▁built . ▁P - 6 0 A ▁Pl anned ▁production ▁version ▁of ▁XP - 6 0 ; ▁ 1 9 0 0 ▁ordered , ▁all ▁cancel led . ▁Y P - 6 0 A - 1 ▁Pre - production ▁version ▁of ▁P - 6 0 A - 1 ▁with ▁single ▁prop . ▁Tw enty - six ▁ordered ; ▁two ▁built ; ▁one ▁re built ▁as ▁Y P - 6 0 E . ▁P - 6 0 A - 1 ▁Pl anned ▁production ▁version ▁of ▁XP - 6 0 C ▁with ▁Pr att ▁& ▁Whit ney ▁R - 2 8 0 0 - 1 8 ▁engine ▁and ▁contra prop ; ▁arm ament : ▁four ▁. 5 0 - cal ▁M G . ▁ 5 0 0 ▁ordered ; ▁cancel led ▁before ▁any ▁built . ▁XP - 6 0 B ▁Curt iss ▁Model ▁ 9 5 B ; ▁V - 1 7 1 0 - 7 5 ▁engine ▁with ▁SU - 5 0 4 - 2 ▁tur bos uper char ger ; ▁arm ament : ▁six ▁. 5 0 - cal ▁M G . ▁One ▁built , ▁modified ▁to ▁XP - 6