[3] The design of these complete missile systems was undertaken by the Royal Aircraft Establishment at its facilities in Farnborough and Bedford.[5] Businesses include a division of Norwegian company Nammo, which continues design and manufacture of the LEROS rocket engines, developed by Royal Ordnance; Airborne Engineering Ltd whose capabilities include rocket system design and testing;[6] and Reaction Engines Ltd, who began construction on a rocket test facility to develop their SABRE rocket engine concept in 2017.[8] [9] [10] [11] [1] [12] In 2016, the UK Government announced plans to develop a National Propulsion Test Facility at the site,[13] which opened in 2021.Reaction Engines Ltd contributed their heat exchange technology, allowing the exhaust gasses to be quickly cooled from 2000°C to 50°C.[14][15] Example British rocket and missile programmes with RPE involvement follow, many of which were eventually abandoned: