A relic from one of the most daring and astonishing acts of heroism in the skies during World War One is to be offered for sale in Ely.
In 1917, pilot Eric Waters was flying over Belgium when he was shot and killed - leaving his gunner-observer sitting in front of him with no parachute, heading for the ground.
Sergeant Fred Slingsby, however, wasn't going to submit to gravity.
He climbed from his seat then scrambled over the fuselage to where Waters was slumped at the controls.
He then climbed in, sat on his dead colleague's knee and safely took the plane back to British lines where he managed to land it.
For his act of aeronautical derring-do he was awarded the Military Medal.
The item for sale is the pocket watch that pilot Lieutenant Eric Gordon Waters had with him on the doomed mission.
It was taken from his body after the landing and along with his RFC cap and lapel badges was returned to his family.
Relatives engraved the watch as a permanent reminder of the action in which he died aged 30.
It is for sale at Rowley's auction house in Ely on December 7 with an estimate of £400-600.
Roddy Lloyd from the saleroom said: "Waters was part of No. 6 Squadron, Royal Flying Corps, and on January 24 2017 was flying over Poperinge, West Flanders, Belgium.
"Waters was flying his BE2g 7175 whilst escorting a photographic patrol.
"His plane was attacked and during the dog fight he was shot in the back and head and killed.
"Fred Slingsby was sitting in front of him and did not have a parachute because at that time the high command considered it would be an easy option for airmen to jump to safety rather than stay and fight.
"So he climbed from his cockpit over the plane to where Waters was and proceeded to fly the plane back to safety, sitting on the dead pilot's lap.
"It was an extraordinary bit of flying skill and clearly winning the Military Medal meant his commanding officers were impressed."
After the war Fred Slingsby founded Slingsby Sailplanes and then Slingsby Aviation - and is famous for the Slingsby gliders.
He died in 1973 aged 78.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here