Royal Air Force and replacement by the F-35, the RAF Lossiemouth-based 15 (Reserve) Squadron (the Tornado Operational Conversion Unit) was disbanded in March 2017. Lightning: On 23 November 2015 it was announced that a total of 138 F-35Bs will be ordered. 617 (The Dambusters) Squadron officially reformed on 18 April 2018 as an RAF Lightning Squadron. The first four aircraft arrived at RAF Marham on 7 June 2018. The Sentry AEW1, based at RAF Waddington, provides airborne early warning to detect incoming enemy aircraft and to co-ordinate the aerial battlefield. The Sentinel R1 (formally known as ASTOR – Airborne STand-Off Radar) provides a
RAF-977 assembly capacity (only 3000 units a year) at the RAF plant (which still used trolleys, rather than a modern assembly line), its production started at the ErAZ factory in Yerevan, Armenia, 1 May 1966 as ErAZ-762. This was nicknamed "Yeraz" (Armenian for "dream"). By 1973, ErAZ's production reached 6,500 per year; with the innovation of overhead carriage, capacity almost doubled, to 12,000 a year. The 977 was also produced under licence by "Lugansk Avto Remontnyi Zavod" (LARZ). In 1969, an improved ErAZ-762A also appeared. Production of the RAF-977 ceased in 1975, when it was replaced by RAF-2203 Latvia. The 977