The McDonnell design was therefore reworked into an all-weather fighter-bomber with 11 external hardpoints for weapons and on 18 October 1954, the company received a letter of intent for two YAH-1 prototypes.
O deseño de McDonnell foi polo tanto revisado para convertelo nun cazabombardeiro todo-tempo con 11 soportes externos, e o 18 de outubro de 1954 a compañía recibiu unha carta pedindo dous prototipos do YAH-1.