 In 1953 , McDonnell Aircraft began work on revising its F3H Demon naval fighter , seeking expanded capabilities and better performance . The company developed several projects including a variant powered by a Wright J67 engine , and variants powered by two Wright J65 engines , or two General Electric J79 engines . The J79 @-@ powered version promised a top speed of Mach 1 @.@ 97 . On 19 September 1953 , McDonnell approached the United States Navy with a proposal for the " Super Demon " . Uniquely , the aircraft was to be modular — it could be fitted with one- or two @-@ seat noses for different missions , with different nose cones to accommodate radar , photo cameras , four 20 mm ( .79 in ) cannon , or 56 FFAR unguided rockets in addition to the nine hardpoints under the wings and the fuselage . The Navy was sufficiently interested to order a full @-@ scale mock @-@ up of the F3H @-@ G / H , but felt that the upcoming Grumman XF9F @-@ 9 and Vought XF8U @-@ 1 already satisfied the need for a supersonic fighter . 
