EWR VJ 101 the VJ 101C did not proceed to production status, various other projects of the era to develop supersonic-capable VTOL fighter aircraft, including the Mirage IIIV and the Hawker Siddeley P.1154 (a supersonic parallel to what would become the Hawker Siddeley Harrier, a subsonic VTOL combat aircraft that reached operational service), ultimately met similar fates. The Harrier jump jet and, substantially later, the Lockheed Martin F-35 Lightning II, has since demonstrated the potential of VTOL fighters. EWR VJ 101 The EWR VJ 101 was an experimental German jet fighter vertical takeoff/landing (VTOL) tiltjet aircraft. VJ stood for "Versuchsjäger", (German for "Experimental
Hawker Siddeley Harrier funding that was available. Following the Harrier's entry to service the focus switched to improving reliability and extending engine life; a formal joint US–UK Pegasus Support Program operated for many years and spent a £3-million annual budget to develop engine improvements. Several variants have been released; the latest is the Pegasus 11–61 (Mk 107), which provides 23,800 lbf (106 kN) thrust, more than any previous engine. The Harrier has been described by pilots as "unforgiving". The aircraft is capable of both forward flight (where it behaves in the manner of a typical fixed-wing aircraft above its stall speed), as well