The quinjet is atop the Avengers Headquarters at DCA's Avengers Campus.
"The Quinjet is a jet used frequently used by S.H.I.E.L.D. and the Avengers. As the successor to the Quadjet, Quinjets possess unique flight capabilities thanks to their unique wings which contain turbine fans. While most Quinjets are lightly armed, Project Insight introduced a series of Quinjets with a wider range of weapons." (
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