Crammed together in their unwieldy aircraft and utterly dependent on one another, the bomber crews of the Second World War forged friendships that often only death could break.
Which is why Pilot Officer Reg Wilson never forgot the night more than 60 years ago when he lost two friends in the night skies over Germany.
As he entered his old age - the memories of his youth perhaps more powerful than ever - Mr Wilson began a quest to find their remains.
Yesterday he told how at last he had succeeded in finding one of those friends, flight engineer Sergeant John Bremner, and finally laying him to rest.
Sergeant Bremner will be buried with full honours at the Heerstrasse War Cemetery in Berlin next Thursday.
'It's only right that John is honoured,' said Mr Wilson, of Chigwell, Essex.
'Thousands of good men, like John, lost their lives. It must not be forgotten. It will be an emotional, but happy, day.'
Sergeant Bremner died aged 21 on the night of January 20, 1944, when 800 aircraft raided the German capital.
Among the 27 aircraft lost was Halifax LW337 from 102 Squadron based at RAF Pocklington near York.
The aircraft - nicknamed Old Flo by her eight-man crew - was heading for home when she was hit by anti-aircraft fire.
Long search: Pilot Officer Wilson and Sergeant John Bremner
Woodland hunt: Reg with wife Barbara in the woods in Koepenick, Germany, where the plane was discovered 60 years after it went down
Another survivor from Old Flo, rear-gunner Sergeant John Bushell, 84, said: 'It burst into flames from wing tip to wing tip.
'I was thrown out after hitting my head on a gun. I came to in free-fall and managed to pull the chute.'
Both he and pilot Mr Wilson, along with bomber aimer Flying Officer Laurie Underwood, now 86, and pilot Flying Officer George Griffiths survived and became prisoners of war.
A Halifax bomber like the one shot down as it approached Berlin 60 years ago
The bodies of second pilot Sergeant Kenneth Stanbridge and wireless operator Pilot Officer Eric Church were buried after the war.
But Sergeant Bremner and gunner Warrant Officer Charles Dupueis were never found.
Mr Wilson, 85, a former management consultant, began his search for answers in 2005 when he travelled to Berlin with his daughter, Janet Hughes, 46, who speaks fluent German.
They met local historians and witnesses and the next year, he returned and found the wreckage with the help of a team of volunteers using metal detectors.
War heroes: George 'Gag' Griffiths and Sergeant Kenneth Stanbridge
Reg shows off some of the debris from the crashed Halifax bomber
Final confirmation that the remains belonged to Sergeant Bremner, of Elswich, Northumberland, arrived after a DNA sample was taken from his sister Marjorie, 89, who will also attend his burial.
Mr Underwood, of Wetherby, West Yorkshire, is too ill to go and Mr Griffiths died in 1998.
A Royal British Legion spokesman said Mr Wilson's quest 'spoke of the searing and life-long impact of service in the armed services. People don't put away their war memories easily.'
Survivors: Sergeant John Bushell and Flying Officer Laurie Underwood
Some 55,500 young men of Bomber Command died during the war.
Last night Mr Bushell, of Oakley, Bedfordshire, added: 'My abiding memory of John is singing our hearts out together at a piano bar in York. He was a war hero who gave his life for his country.'
Former RAF Rear Gunner John Bushell holding his Prisoner Of War ID Card which he took from the prison office when he was freed