In addition, the USAF continues to fund development work of the Aerojet (formerly Atlantic Research) Variable Flow Ducted Rocket ramjet system as a future propulsion option for an extended range AAM.

此外，美国空军继续投资于航空喷气研究所（大西研究所）变喷流管火箭发动机系统，将其作为增程空空导弹未推进选项。