The General Dynamics F-111 was the first variable-geometry combat aircraft which to enter into operational service. It also pioneered technical novelties such as afterburning turbofan engines, terrain-following radar and an advanced-attack radar system. Although its development was marred by delays, technical issues, political controversies, budget-overruns and troublesome operational service debut, the Aardvark overcame many hurdles and eventually matured into a very capable and versatile combat jet, which soldiered on for over four decades.