A potential disaster was narrowly averted when a packed passenger plane took off just seconds before it was about to leave the runway due to a software glitch.
The Boeing plane, operated by TUI, was taking off from Bristol Airport to Las Palmas, Gran Canaria on March 9 with 163 passengers on board when it struggled to take off.
The 737-800 aircraft cleared runway nine with only 800 feet of asphalt remaining at an altitude of 35 feet.
The aircraft then flew over the nearby A38 road at an altitude of just 30 meters (100 feet), at a speed of approximately 150 knots (approximately 173 mph).
The A38 is a major busy A-class road connecting South West England with the Midlands and the North.
The Air Accidents Investigation Branch (AAIB), part of the Ministry of Transport, said the incident was the result of insufficient thrust during takeoff.
Pilots manually set the thrust level after a software glitch that Beoing was aware of before takeoff.
“A Boeing 737-800 completed a take-off from runway 09 at Bristol Airport with insufficient thrust to meet regulated performance,” the AAIB report said.
“The autothrottle (A/T) was disengaged when the takeoff mode was selected, at the beginning of the takeoff roll, and subsequently the thrust manually set by the crew (84.5% N1) was less than the required takeoff thrust (92.8% N1). .
“Neither pilot noticed at the time that the thrust was incorrectly set and was not picked up via standard operating procedures (SOPs).”
The plane’s acceleration was significantly slower than that of 99.7 percent of other planes of the same model leaving the same airport, according to performance data collected by the AAIB.
The autothrottle system on a Boeing 737-800 can control thrust from takeoff to landing, the AAIB added.
Boeing told investigators investigating the incident that they were aware of a “long history of nuisance interruptions during takeoff.”
It added that the aircraft was equipped with an FDR recording device, known as a ‘black box’, which records flight data, and a CVR, which records recent sounds in the cockpit.
The AAIB said: “G-FDZS was equipped with both an FDR and a CVR. The CVR mounted on the G-FDZS was not removed from the aircraft as it continually overwrites itself and only retains the last two hours of audio.
“As such, the recording of the take-off during the flight to Las Palmas would have been overwritten. However, the FDR has been deleted and downloaded.”
The incident is the latest in a series of problems with Boeing jets in recent years.
The aerospace giant’s safety standards are increasingly coming under scrutiny after various investigations recent incidentsincluding one where a disused door fell off a brand new 737 Max shortly after takeoff. There were no injuries.
In April, a FedEx Airlines Boeing cargo plane landed at Istanbul airport without its front landing gear deployed but managed to stay on the runway.
Five years ago, Boeing agreed to pay $2.5 billion and then improve safety two new 737 Max jets crashed within a span of five months – one in Indonesia in 2018 and one in Ethiopia in 2019, killing a total of 346 people.
In May, US officials warned Boeing that it could face criminal charges following claims, the airline failed to improve aircraft safety and adhere to a settlement following the deadly 737 crashes.
A spokesperson for TUI UK&I said: “We have been working closely with the authorities to provide all available information.
“The AAIB recommendations and lessons learned from this launch will support the entire aviation sector and other airlines. The safety of our passengers and crew is always our top priority.”
Boeing was contacted for comment.