Plane crash and fatalities narrowly avoided in Belfast International Airport incident - report
A plane could have crashed with multiple fatalities after it hit a runway light at Belfast International Airport, a report has found.
That was the conclusion of a report by the Air Accidents Investigation Branch (AAIB) into an incident on July 21 this year involving a flight to Corfu in the afternoon.
There were 185 people on board including six crew.
The AAIB has put out a special bulletin on the incident to inform others so that the same mistake is not made.
An investigation found that outside air temperature data was incorrectly entered into the plane's flight management systems which meant it was slow to accelerate off the runway.
Witnesses said they noticed the Boeing 737 take a "significant time to lift off before climbing at a very shallow angle".
A wheel of the plane subsequently hit and damaged a light almost 30 metres off the end of the runway.
Such was the seriousness of the incident, the AAIB determined it required "in-depth investigation".
It said that in "slightly different circumstances, this event could have resulted in the loss of the aircraft with multiple fatalities".
"Examples of such circumstances considered were: the same event taking place on a slightly shorter runway than was actually the case with the aircraft unable to lift off before the end of the runway; obstacles or terrain in the takeoff path; or engine failure ... with a decision by the commander to continue the takeoff."
The report did not give details of the plane operator. There is nothing in the report to suggest wrongdoing on the part of Belfast International Airport or Boeing.
The incident was not reported by aircraft commander, aircraft operator or the tour operator to the AAIB but was reported to the Transportation Safety Board in Canada by the aircraft operator, the report found.
Air traffic controllers at Belfast International Airport also reported the incident.
However, because the AAIB only became aware of the incident 58 hours after the event it meant crucial recording material was lost.
"This has been detrimental to the investigation and may hinder the identification of all the safety issues," the report said.
The AAIB concluded that the only way for the thrust setting to be wrong was for an incorrect figure for the outside air temperature to be input to the take-off systems. The report said there was no indicator to alert pilots to the error and there had been examples in the past of pilots not noticing slow acceleration for take-off.
Investigators said that the software was not up-to-date and a later version would reject temperature data if it did not correlate with sensor readings.
"The updates to the software are offered by Boeing as upgrade service bulletins at nominal cost," the report said.
The report recommended operators update the flight management software on all Boeing 737 planes. It also advised Boeing to inform operators who use the 737 of the incident in order to highlight the importance of the matter.
"Given the serious potential consequences of this type of data entry error, it was considered important to inform Boeing 737 operators of this event," the report said.