Description

On 15 April 1996 a significant loss of separation occurred in daylight when a BOEING 747-400 (international, winglets) being operated by British Airways and having just taken off from runway 27R at London Heathrow came into conflict to the west of the Airport with an AIRBUS A-300-600 being operated by Emirates which had just, upon ATC instruction, commenced a missed approach from the parallel runway 27L.

Investigation

An Investigation was carried out by the UK AAIB which established by reference to the ATC Separation Monitoring Function(SMF) equipment which monitors aircraft separation but is not contemporaneously displayed to controllers, that "at their closest proximity the two aircraft were between 600 and 700 feet apart vertically and between 0·71 and 0·82 nm horizontally.

The event happened shortly after a third aircraft had burst a tyre during a landing on runway 27L some 3 minutes earlier. The response to this circumstance led to an expected temporary increase in controller workload in circumstances where the two runways were under the control of separate TWR ATCOs and with one runway designated for landings and one for take offs.