First flight of the -100 occurred on 3 September 1981, with deliveries commencing in 1983. The launch customer in March 1983 was Dan-Air, soon followed by the RAF's Royal Flight. The -100 was the last of the 146 series designs to be developed into the Avro RJ standard with first deliveries of the Avro RJ70 in late 1993. The RJ70 differed from the 146-100 in having FADEC LF 507 engines and digital avionics. The RJ70 seats 70 passengers five abreast, 82 six abreast or 94 in high-density configuration. The Queen's Flight acquired a total of three 146s, all were fitted out with a luxurious bespoke interior. The aircraft are operated in a VIP configuration with a capacity of 19 passengers and 6 crew. The BAe 146-100QC is the convertible passenger/freight version and the BAe 146-100QT (Quiet Trader) is the freighter version. The BAe 146 is powered by four Avco Lycoming ALF 502 turbofan engines, which are fixed on pylons underneath the aircraft's high wing. The ALF 502 was derived from the Lycoming T55 turboshaft powerplant that powers the Chinook heavy transport helicopter. Notably, the ALF 502 had a very low level of operational noise, much lower than most other competing aircraft, this was achieved partly by the engine's high bypass ratio along with additional sound dampening layers built into the engine.