@boneyardsafari: Checking outing the Harrier Fort Worth Aviation Museum! #av8b #boneyardsafari #aviationsafari

Obama :

without looking it up probably a Vulcan

Adam Holliday65 :

Aden 30 mm cannon for the UK Harrier - not sure if the US uses a Vulcan

𝑬𝑪𝑯𝑶_𝑨𝑳𝑷𝑯𝑨 :

StupidMetalWiddler :

GAU-12 25mm Cannon. Fun fact, it uses the engine air to power the gun. 😁 That Cannon is also known as The Equalizer...😁😁