Several Visiontrons at Nellis Air Force Base are mentioned by the Boomers to be running flight simulators, and that they are using the simulations to train themselves to fly. Pete mentions these simulations include combat flights against Xian-85's, and that he has personally shot down over 500 of them during his VR sessions.
The Xian-85 fighter is mentioned only in Fallout: New Vegas.
Behind the scenes
"Xian" may be a reference of the real-life XAC, Xi'an Aircraft Industrial Corporation, a major Chinese military and civilian aircraft manufacturer.
- The Courier: "How has Nellis taught your people to fly?"
Pete: "Once we restored power, we learned that some elaborate chairs we'd been sleeping in were actually virtual reality simulators. Before you ask, I'm afraid there's no way you can be allowed to use the simulators. They are for our use only. Sorry."