Hawker Siddeley P.1127 Hawker Siddeley P.1127 The Hawker P.1127 and the Hawker Siddeley Kestrel FGA.1 are the experimental and development aircraft that led to the Hawker Siddeley Harrier, the first "vertical and/or short take-off and landing" (V/STOL) jet fighter-bomber. P.1127 development began in 1957, taking advantage of the Bristol Engine Company's choice to invest in the creation of the Pegasus vectored-thrust engine. Testing began in July 1960 and by the end of the year the aircraft had achieved both vertical take-off and horizontal flight. The test program also explored the possibility of use upon aircraft carriers, landing on in 1963. The first three
Take-off warning system indicates the nature of the configuration error. A number of aircraft disasters due to improper configuration have happened in spite of the presence of a functional take-off warning system: Take-off warning system A take-off warning system or TOWS is a set of warning signals required on most commercial aircraft, designed to alert the pilots of potentially-dangerous errors in an aircraft's take-off configuration. There are numerous systems on board an aircraft that must be set in the proper configuration to allow it to take off safely. Prior to every flight, the flight officers use checklists to verify that each of the