Initially flew a tour on Whitley bombers with 10 Squadron and then joined the Wireless Development Unit (later 109 Squadron) gathering information about a radio beam from a transmitter near Cherbourg which was used by the Luftwaffe to guide German bombers to targets in England. These missions provided information for the scientists at the Telecommunications Research Establishment (TRE) who developed a similar aid. This led to the development of Oboe – so called because the radio tone, heard by the aircrew using the aid, was similar in note to the musical instrument. The system was based on the transmission of a radio beam from ground emitters located on the East coast and aimed at the target. A dot or dash in the pilot’s earphone would indicate whether the aircraft was to the right or left of the beam – a steady note indicated that the aircraft was flying on the beam. The navigator would be listening for the radio signal which determined the moment to release the bomb. Keith Somerville (KS) was one of five pilots who flew over Germany perfecting oboe. Flying a Mosquito KS and his navigator took part in the first oboe raid on December 20th 1942 - the attack achieved moderate success. Refinements were made and on the 5th March 1943 KS flew one of five Mosquitos used to mark the Krupps factory at Essen – some of the markers fell within 75 yards of the factory. Arthur Harris remarked ‘this was the precise moment that Bomber Command’s main offensive began.’ After two years with 109 Squadron KS was posted on a ‘rest tour’ to Pathfinder HQ. Some Lancasters were fitted with Oboe and through still on a ‘rest tour’ KS was the pilot of the first oboe equipped Lancaster operation which took place on the 11th July 1944. Four days before this operational flight KS had flown a Mosquito to France to collect the top secret oboe equipment salvaged from a Mosquito that had crashed in an area of fierce fighting near Caen. In October 1944 KS returned to operational status as squadron leader of 105 Squadron the second oboe equipped Mosquito squadron. In March 1945 he was promoted to group captain having flown 117 operational flights over enemy territory. In April 1945 the Mosquitos of 105 Squadron used their oboe equipment to pinpoint precise locations in western Holland to allow the main bomber force to drop food supplies to the starving Dutch people – Operation Manna.