A pilot who crashed his light aircraft into a tree on a golf course underestimated the fuel needed for his flight, investigators have said.
Vince Hagedorn made a forced landing on Caird Park Golf Course, Dundee, in August 2009 after his engines stopped.
The pilot, from Essex, attributed his lucky escape to his love of Biggles adventure stories.
The 64-year-old said he copied his landing from a story about the fictional WWI flying ace.
The Air Accidents Investigation Branch (AAIB) said the average fuel consumption assumed by the pilot was "insufficient to account for operational realities".
Mr Hagedorn set off alone from Walney Island Airfield in Cumbria, to Kinloss, Moray, on 13 August 2009, considering Dundee airport as an alternative.
Cloud patterns on the flight path forced the pilot to use more power climbing and dropping in altitude.
After crossing the Firth of Tay in his three-year-old CTSW aircraft, he saw his right-wing fuel tank was empty and only 10 litres remained in the left tank.
Turning south to Dundee, he said only five litres remained before reporting his aircraft had run out of fuel.
The AAIB bulletin continued: "He reported that initially the most favourable landing area appeared to be nearby playing fields but, noticing that these were occupied by children, he turned towards an adjacent golf course.
"However, the fairways also appeared congested, so the pilot decided to land in a tree."
Management consultant Mr Hagedorn was helped out of the plane by emergency services and treated for minor head injuries at the Dundee's Ninewells Hospital.
A study of the P&M Aviation craft found no fault with the fuel lines and no evidence of pre-impact engine component failure.
But tests on the fuel system showed the aircraft design was "not conducive to accurate gauging".
The AAIB said the pilot was convinced from the indication of fuel tank contents that he was not about to run out.
Investigators recommended the manufacturer revises its assessment of usable fuel in the CTSW aircraft.
P&M Aviation intends to publish a letter explaining the effects of aircraft attitude and turbulence on fuel feed at low fuel levels.
Speaking from his hospital bed after the incident, Mr Hagedorn said he had recalled one of Captain WE Johns' adventures about James Bigglesworth, when he realised he was about to crash.
"There's a story where Biggles has his engine shot up over enemy lines," he said.
"He tries to get back to the airfield and doesn't quite make it and ends up with no height over a wood.
"What he does is he flies into the wood, and, as he flies into the wood, he pulls the stick back to pancake onto trees - and I just did that. I just stalled into the tree."