Pilot exclamations on the cockpit voice recorder of the crashed TAM Brazilian Fokker 100 (Flight International, 6-12 November) have led investigators to suspect that the No 2 engine thrust-reverser may have operated in flight, say sources close to the investigation. This is supposed to be impossible, because the thrust-reverser actuators are isolated from the regional-jet's flight-deck controls by touchdown-switches. Northrop Grumman manufactures the thrust reversers on the aircraft's Rolls-Royce Tay engines.
A Lauda Air Boeing 767 crashed in Thailand in May 1991 following uncommanded asymmetric thrust-reverser deployment. The cause was never proven, but the design has since been changed.