In 2002, the Bedford Unified control concept was selected for the JSF STOVL variant. JSF BF-01 is illustrated opposite under the flight control of the Bedford Unified control method. XW175 was also part of the Empire Test Pilots School’s training syllabus for a few years at this time.
The JPO continued to support further STOVL developments with several ship trials with XW175 and HMS Illustrious, HMS Invincible and the French carrier, Charles de Gaulle. These trials introduced guidance techniques for automatic recovery along side a ship with an automatic vertical landing capability, some 30 years after the original HMS Hermes trials with XW175 in 1977 and some 35 years after the certification of Civil automatic landing systems back in the BLEU days. Technology advancements had bridged this time period and the gradual acceptance of the new control concepts.
With the established STOVL flight control standard, XW175 in its new livery continued to support JSF recovery requirements to ships with a 60 knot airspeed approach and landing method referred to as ‘Ship Rolling Vertical Landing’ (SRVL). This approach speed provided JSF with ship recovery flexibility as a percentage of wing lift at this airspeed would offset engine direct lift and enhance safety margins.
In conjunction with this programme ship deck lighting was developed for poor visibility and night recovery to ships. This programme produced the new ‘Bedford Array’ of deck lights to provide an unambiguous touch down point irrespective of the ship deck motion. The ‘Bedford Array’ with SRVL provided an effective and alternative solution to ship recovery at night in poor visibility and hence operational flexibility.