Operation CHASTISE & Benson’s part in it The 80th Anniversary of the raid

Mick Prendergast

On May 17th 1943, 617 Squadron dropped their rotating mines to bounce along the water until they hit a dam wall and sank before exploding at the predetermined depth.

After the raid they needed to know if the mines designed by Barnes Wallis were successful or not.

A photographic sortie was required in order to get the answer, so RAF Benson was called upon to send someone to find out. Flying Officer

Frank Jerry Fray of 542 Squadron was the man of the moment, his name was at the top of the list so he was given the task D/578 to fly along the Ruhr valley and locate the Ader, Mohne and Sorpe dams.

Frank or Jerry as he was nicknamed started his military career in the Army. His parents thought that flying was too dangerous and persuaded Jerry to join the Army instead.

So Jerry became 1915377 Driver in the Royal Engineers. He was soon mobilised and sent off to France. There he was attached to no 4 Squadron RAF who flew Westland Lysander aircraft in Belgium.

During his time there he witnessed the loss of eleven aircraft before the squadron was told to leave and make for the Dunkirk beach. Thankfully Jerry managed to avoid the enemy bombardment without injury and got back to the UK. Back safe and sound he decided that the Army was the dangerous service and promptly applied to join the RAF as 656657 Pilot Officer.

He was accepted and after collecting his wings he volunteered for Special Duties. His ‘duties’ found him eventually posted in 1942 to RAF Benson as a Photographic Reconnaissance pilot.

On the 15 May 1943 his 36th operational sortie, he flew over Soest area to the Ader, Mohne and Sorpe dams along the Ruhr valley to verify that the water behind the dams was at its highest so if the dams were breached then the water would have maximum effect and give greatest devastation.

On the night of the 16 / 17th May, number 617 Squadron attacked the three dams by dropping spinning mines around midnight onto the Mohne dam.

Early morning on 17th May Jerry’s name became at the top of the operation list so he prepared himself to fly once again along the Soest area of the Ruhr valley.

Flying in Vickers Supermarine Spitfire EN343 he left Benson at 0725. His Spitfire was originally on the Mark V production line but removed and refitted with a larger Rolls Royce M61 engine. This made the aircraft an early make of the Mark XI Spitfire.

At 11am Jerry returned to Benson where the photographic section staff removed the cameras and sent the film to the development section in Ewelme village.

In the photo section was 2006768 Margaret Irwin and it was she that took out the film and put it through the process of development. Waiting outside was an officer who was eager to see the results and telephone those concerned with the operation.

What is not known about this operation is that at 0910

Flying Officer Eric George Searle aged 23 left Benson in EN346 to fly task D/581 on the same route as Jerry just in case he did not return. Eric Searle landed back at 1240 but by then what was needed to be known was officially known.

Jerry was awarded an immediate Distinguished Flying Cross while his Squadron companion Eric was only given eggs and bacon.