Fokker D.VII
The Fokker D.VII was a type of fighter aircraft used in the mirror universe on Earth during an otherwise unspecified conflict. ( opening credits)

Appendices

Background information
Although not mentioned by name, the Fokker D.VII appeared in the opening credits, indicating the craft was manufactured and used in that universe.

This is not actual historical footage, as filming technology was simply not advanced enough – not to mention its equipment being then far too cumbersome to put plane and pilot at unwarranted risk in combat situations – in the World War I-era to capture this kind of live action imagery, but rather a clipping from the 1927 Paramount Pictures silent war movie Wings.  Pictured is an American  standing in for a German  fighter aircraft, after having been dressed in German livery with the type designation painted on the tail.

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Earth vehicles
Mirror universe