The new aircraft would also get more powerful engines with longer afterburners. The new aircraft was designated the F-101B by the Air Force though the manufacturer suggest the F-109. Some major modifications were need to the front of the aircraft to accept a twin cockpit, the large radar and a means to carry air-to-air weapons. Delays to the USAF WS-201 interceptor programme lead to calls for an interim aircraft to be brought into service, a design programme which was eventually won by McDonnell using the original F-101 Voodoo as the basis for the new aircraft.
