Gibson's aircraft crashed at Steenbergen in the Netherlands at around 22:30 and lit up in flames. Witnesses heard an aircraft flying low, saw that its cockpit was illuminated and then it crashed.
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One theory advanced is that the accident was due to Gibson's lack of experience flying Mosquitoes. His log book, which he had last updated on 16 September, detailed 9 hours and 35 minutes flying Mosquitoes.
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Lack of fuel is the explanation most favoured by members of No. 627 Squadron at the time. In December 1985 the site was excavated and wreckage from the plane recovered. No enemy damage was noticeable. It has therefore been suggested that Gibson and Warwick had failed to switch fuel tanks at the correct time.[163] It has also been suggested there was a fault with the fuel tank selector.[164] Further, it is possible that a lack of familiarity with the Mosquito resulted in neither Gibson nor Warwick being able to find the switches to swap the fuel supply. This would also be a reason to explain why the cockpit was illuminated: they were attempting to locate the switches. In either case, the result would be that the aircraft simply ran out of fuel.