The Air Accident Investigation Branch (AAIB) described a fire that broke out on a Ryanair plane at Manchester Airport as a ‘serious incident’.
The report, published in January 2023, detailed how the Boeing 737-8AS landed at 12.45am on March 12, 2022, without any issues, only for a fire to break out on the plane’s wheel due to a ‘fatigue crack’.
After landing on the runway, the crew were cleared to taxi to the airport’s Terminal 3. Once on the taxiway, they found that to maintain normal taxi speed a ‘higher-than-normal’ thrust was required.
The crew presumed this was due to a flat tyre, so continued as usual and experienced no problems in keeping straight despite the increased thrust.
According to the AAIB’s report, as the aircraft approached the stand, the crew heard calls over the radio for the fire service to attend a plane with ‘brakes on fire.’
The fire on the left main landing gear wheels was extinguished and the crew decided an emergency evacuation was not necessary.
Describing the cause of the fire, the AAIB report said: ‘Whilst taxiing to the gate after landing, the outboard wheel on the left main gear failed because of a fatigue crack in the wheel hub.
‘The wheel failure caused a hydraulic leak from the brake piston and the heat generated by the misaligned wheel caused the hydraulic fluid to combust, resulting in a fire.’
The report added that the ‘left main wheel inner hub had fractured’ and the resulting misalignment of the wheel had ‘damaged the brake piston, causing a hydraulic fluid leak.’
It concluded that the ‘heat generated by the misaligned wheel… was sufficient to ignite the hydraulic fluid.’
Following the incident, the wheel manufacturer developed an ultrasonic inspection technique to look at the internal bore of the wheel hub and identify the presence of cracks. Ryanair has now introduced the checks on its fleet of Boeing 737-8AS aircraft.
A Ryanair spokesperson said: “Ryanair fully participated in this AAIB investigation and we welcome the report in which there are no safety recommendations for Ryanair.”