Accidents
LOT Flight 282
Summary:
Incorrect data input to the Flight Management System, ‘E’ rather than ‘W’, meant loss of instruments. Aircraft had to return to Heathrow.
Details:
On 4 June 2007, just after take-off from Runway 09R at London Heathrow Airport (LHR), the pilots noticed that most of the information on both of the Electronic Attitude Director Indicators and Electronic Horizontal Situation Indicators had disappeared. The aircraft entered Instrument Meteorological Conditions (IMC) at about 1,500 feet Above Aerodrome Level (AAL), and the co-pilot had no option but to fly using the standby attitude indicator and standby compass. He experienced difficulty in following radar headings. The aircraft returned to land at LHR after a flight of 27 minutes.
A single error made by the co-pilot during the pre-flight preparation caused the subsequent problems. This was the use of ‘E’ instead of ‘W’ when the longitude co-ordinates were entered into the Flight Management System (FMS).
The airports around London, because of their proximity to the Prime Meridian, can lead flight crews to make co-ordinate entry errors of this nature. It is of note that the operator’s route network is such that there are few destinations to the west of the Prime Meridian and hence the majority of longitude co-ordinates that need to be entered would be eastings. Inertial Reference System (IRS) alignment warnings should have alerted the crew but may have been dismissed.
This incident highlights the importance of the integrity and fidelity / representation Data Properties, specifically with respect to co-ordinates.
Links
- https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/384859/Bulletin_6-2008.pdf
(accessed 29 November 2017).