During the early development of the Panavia MRCA ( i.e. the Tornado ) it became apparent that the development of the variable geometry aspect of the design was running into problems, and the resulting budget overrun could see the project halted. Panavia therefore proposed a simplified design, with a fixed delta wing. The deletion of the VG wing created additional space within the fuselage, which no longer needed to house the wing box and associated actuators, substantially increasing the amount of fuel which could be carried internally, which the fuel tanks in the new wing also added to. The aircraft therefore rarely needs to carry external tanks, unless on a long range ferry flight, leaving all the wing hardpoints available for weapons.
Matchbox F.3 fuselage, Hasegawa F-106 wings