Dambusters' release button for 'bouncing bombs' to sell

This bomb release button from a Lancaster Bomber of 617 Squadron is expected to fetch up to £40,000, auctioneers said

The button from a plane used to release a "bouncing bomb" that destroyed a key dam during World War Two is to be auctioned.

The mission involving the Lancaster Bomber from 617 Squadron was later immortalised in The Dambusters film.

Its bombs destroyed the Möhne Dam in Germany on 17 May 1943.

Northamptonshire auctioneers said it was expecting the Bakelite button to fetch between £25,000 and £40,000 when it goes on sale at the weekend.

The bombs caused catastrophic flooding of the Ruhr Valley, playing a role in "almost certainly shortening the war," according to Jonathan Humbert, of J P Humbert Auctioneers.

Pupil acquired items

According to Mr Humbert, the button was pressed by Pilot Officer John Fort on board Lancaster bomber ED 906 AJ-J, which was piloted David Maltby and was the fifth aircraft to attack the Mohne Dam.

Squadron Leader David Maltby, gave the button and other items from the plane to the Hydneye House school museum where his father was headmaster.

When the school closed a former pupil acquired the historic items.

They included four large marbles used by bouncing bomb inventor Barnes Wallis in the development of his weapon.

Marbles used by the bouncing bomb inventor Barnes Wallis

An altimeter is also on sale

The marbles and an altimeter especially fitted at eye level to bomber ED932 AJ-G piloted by Guy Gibson to aid in low-level flying on approach to the doomed Möhne Dam will also be auctioned, together with a cockpit blackout blind from Gibson's plane.

Mr Humbert said: "These are incredibly rare and very historic items of a simply unrepeatable nature. I anticipate global interest in these evocative and iconic pieces of 20th century British history."

Cockpit blackout blind from a Lancaster bomber