British Airways is facing a safety investigation after three of their jets were on the ground for three days due to insect infestation just seconds before take-off from Heathrow.
Two of the planes sped across the runway when pilots successfully aborted takeoff after discovering that key speed sensors were malfunctioning.
A third jet is believed to be moving towards the runway when the pilots noticed a similar error and returned the aircraft to its standing position.
Later research found that insects had crept into the aircraft’s air speed sensors, called pitot tubes, causing blockages that gave incorrect speed readings.
Similar incidents are known to have resulted in aircraft crashes in the past because pilots and automated fly-by-wire systems can be confused by inaccurate airspeed data.
It is believed that all three BA jets were on the ground between three and seven days when the insect contamination occurred.
Normally, aircraft in the warehouse must have special covers over their pitot tubes to prevent insects or dust from entering.
British Airways faces a safety investigation after three of their jets were on the ground for three days due to insect infestation just seconds before departure from Heathrow [Stock image]
The coronavirus pandemic is said to have exposed more aircraft to the problem as flights were canceled and more aircraft were stored on the ground for extended periods of time.
The Heathrow incidents occurred between June 9th and 11th of this year, when temperatures at the airport rose to 26 ° C, creating ideal conditions for the swarm of insects.
Most serious of all was a BA Boeing 777-200 that took off for Accra, Ghana on June 11th.
The jet was rolling down the runway at nearly 100 mph when the pilots noticed that all three of their pitot tube systems had “unreliable airspeed readings”.
It is believed that the crew used their brakes and reverse thrust to bring the jet to a safe stop.
Passengers were delayed more than five hours before a second jet was deployed to fly them to Accra.
Airbus A320 jets on short-haul flights are said to have been involved in the earlier incidents.
One was denied take-off due to a “flight speed deviation” found in two of its three pitot tubes, while the other was found to have failed due to a single blocked tube.
The Department of Aircraft Accident Investigation of the Department of Transportation has opened an official investigation into the infestation and labeled them as “serious” incidents.
Immediately after the cases became known, the civil aviation authority issued a safety bulletin to the aircraft operator, warning of the dangers of an infestation.
The bulletin states, “Initial feedback suggests that some form of insect infestation may have contributed to these events.”
It warned operators to be aware of the risks of aircraft resumption of service after “extended parking” during the pandemic.
The bulletin added: “Crews should be made aware of this potential issue and be reminded of the importance of speed controls during take-off taxiing and the actions to be taken in the event of a deviation, as well as the unreliable speed indications associated with them.” For their type of aircraft, they should Discover problem in the air. ‘
A separate AAIB investigation was conducted after a Wizz Air plane canceled its take-off when its speed sensor suddenly failed as it sped down the runway at Doncaster Sheffield Airport at 140 mph.
The incident occurred in June last year when the Airbus A321 was brought to Stansted Airport with no passengers on board after being parked for 12 weeks during the initial coronavirus lockdown.
It was later discovered that one of its pitot tubes contained three tiny insect larvae.
The report found that even with sensor covers in place, the insects could have entered the pipe as they did not seal completely due to possible problems in generating air pressure changes.
The crash of a Boeing 757 with the loss of 189 people in 1996 was attributed to the pilot who was confused by a faulty speedometer shortly after taking off from the Dominican Republic for Frankfurt.
The most likely cause, the investigators saw, that a mud wasp had nested in one of the pitot tubes while the aircraft operated on behalf of Birgenair was on the ground for 20 days.
The Heathrow incidents occurred between June 9th and 11th of this year, when temperatures at the airport rose to 26 ° C, creating ideal conditions for the swarm of insects [Stock image]
A British Airways spokesman said: “Safety is always a top priority and we, like other operators, carry out additional controls as recommended by the CAA.
“With the AAIB investigation ongoing, it would not be appropriate to make any further comments.”
Aviation consultant Paul Beaver told MailOnline: “The most important thing is that the BA flight crews were absolutely on the ball to address this issue. It shows how well trained they are and they should be congratulated on their vigilance.
“There are always pre-start checks and then the pilots do further checks when they go down a runway, which happened here so that there was no danger.
“If they had taken off, the risk would have been minimal, as a pilot has a number of sensors at his disposal.
“Pilots are taught to constantly reference their instruments and they can work around these problems, and they are trained on simulators when situations like this arise.”
“But pitot tube insects are a fundamental problem for everything from gliders to large airliners, and these incidents show that something was wrong with the procedures. It shows the importance of continuous vigilance. ‘