The Siemens-Schuckert DDr.I was a World War I German twin engine, push-pull configuration triplane fighter aircraft. Only one was built, crashing on its first flight.
The Sopwith 2FR.2 Bulldog was a prototype British two-seat fighter of the First World War. A single-engined biplane, the Bulldog was a fighter/reconnaissance aircraft intended to replace the Bristol F.2 Fighter, but was unsuccessful, with no replacement for the Bristol Fighter being purchased.
