AAIB report: Ageing fuel switch gasket blamed for crash landing of historic Spitfire
October 9, 2025
The Air Accidents Investigation Branch (AAIB) has concluded that the engine failure, which led to the forced landing of a historic Spitfire near Hythe, Kent, in May 2025, was caused by the failure of a 70-year-old fuel system component.
The investigation highlights the hidden risks posed by ageing parts within heritage aircraft and has prompted new safety guidance from the Civil Aviation Authority (CAA).
Spitfire engine failure and crash landing near Hythe, Kent
The incident occurred on 3 May 2025, when Spitfire IXT G-BMSB, operated on a Safety Standards Acknowledgement and Consent (SSAC) passenger flight, suffered an abrupt power loss while flying in formation with another Spitfire.
The pilot, an experienced airline transport pilot with more than 7,000 flying hours, was cruising two miles south of Lympne Castle when he detected a slight engine vibration. Within seconds, the aircraft’s Rolls-Royce Merlin 266 engine surged, backfired, and lost power completely.
Noticing a strong smell of fuel in the cockpit, the pilot suspected a fuel-related fault and prepared for a forced landing. He chose an open field, kept the landing gear retracted to maintain speed, and executed a controlled wheels-up landing.
✈️ Historic Spitfire Crash-Lands in Kent Field. Yesterday evening, a remarkable piece of aviation history made an unexpected landing. A 1943 Spitfire, once part of the Royal Canadian Air Force’s 441 Squadron, crash-landed in a crop field near West Hythe, Kent.
— Wesley Baker (@WesleyJBaker) May 4, 2025
Thankfully, both… pic.twitter.com/XeMV1Prfvd
The Spitfire came to rest upright, sustaining damage to the propeller, radiator and wing skin. The pilot escaped unhurt; the passenger received minor bruising.
AAIB identifies failed fuel pressure switch gasket as cause of power loss
AAIB investigators found that the engine failure was caused by a failed gasket within the fuel low-pressure warning light switch, which is attached to the carburettor. Over decades, the gasket had hardened and shrunk, allowing the switch housing screws to loosen.
When the gasket failed, pressurised fuel sprayed into the lower rear of the engine bay and was drawn into the induction system through the air filter. This created an over-rich fuel-air mixture, causing engine vibration, backfiring, and ultimately power loss.
The AAIB noted that the fuel pressure switch was at least 70 years old, and its maintenance history was unknown. The component, designed to alert pilots to low fuel pressure, had instead become the source of the malfunction.
CAA warns historic aircraft operators about ageing fuel system components
The investigation prompted the CAA to issue Safety Notice SN-2025-009, warning operators of vintage and historic aircraft about the airworthiness risks of ageing fuel and hydraulic components.
The notice advises that switches, gaskets, and other tertiary system components—some dating back to the 1940s—can degrade with time and should be subject to regular inspection, functional testing, and calendar life limits. Many of these parts, the CAA said, are still fitted to piston and early turbine aircraft operating in the UK today.
The regulator also urged maintenance organisations to keep accurate overhaul records and to identify components at risk of age-related deterioration such as shrinking, cracking or loss of torque in fasteners.
Pilot skill and emergency training credited for successful Spitfire landing
The AAIB praised the pilot’s judgement and energy management during the emergency. By keeping the landing gear up and maintaining a controlled glide, he avoided excessive drag and preserved sufficient airspeed to reach a safe landing site.
He also delegated radio communications to the pilot of the accompanying Spitfire, allowing him to focus fully on flying the aircraft. The AAIB noted that both occupants were professional pilots and remained calm throughout.
Spitfire pilot walks away from crash landing in Kent – without serious injuries. pic.twitter.com/MpRMEUBpwm
— Global's Newsroom (@GlobalsNewsroom) September 7, 2015
In his post-flight reflections, the pilot credited regular practice, forced landings, and his operator’s “What if?” safety discussions as key factors in achieving a successful outcome.
AAIB report highlights maintenance lessons for vintage and warbird aircraft
The AAIB concluded that the engine power loss was directly caused by a failed gasket, which led to an overly rich fuel mixture and subsequent loss of power. The event, it said, demonstrates how ageing minor components can trigger serious incidents, even when airframes and engines appear well-maintained.
The findings are likely to resonate across the UK’s vibrant warbird and heritage aviation sector, where many aircraft rely on original or period-correct parts. The CAA’s new guidance urges owners and engineers to treat ageing components with the same scrutiny as engines and airframes.
With the AAIB’s report now published, operators of historic piston and turbine aircraft are being urged to take note: the smallest part, if overlooked, can make all the difference between flight and forced landing.
