No 109 Squadron was first formed in 1918 as a bomber training unit and disbanded in 1919. In December 1940 the squadron was re-born from the Wireless Intelligence Development Unit (WIDU). Using Anson and Wellington aircraft it was engaged during the next two years in development of radio counter-measures and also new radar aids, notably the blind bombing system known as Oboe. In August 1942, No 109 moved to Wyton to become one of the original units of the Pathfinder Force. In December it converted to Oboe Mosquitoes and made history by flying the first Oboe sortie over enemy territory on a calibration raid against a power station at Lutterade in Holland.
On the night of 31 December 1943, it made history again when it pioneered Oboe target marking for a following force of heavy bombers. One of No 109's most outstanding successes was on 5/6 March 1943, when its Mosquitoes led Bomber Command's devastating assault on Essen which laid waste more than 160 acres of that city and heralded the Battle of the Ruhr. Included among the squadron's many other wartime claims to fame is the claim that the last bombs to be dropped on Berlin were dropped by one of its Mosquitos at 2.14am on 21 April 1945.
The cover is cancelled with BFPS postmark for the 60th Anniversary of the Battle of the Ruhr which No 109 Squadron took part in.
Hand signed by Group Captain R.C.E. Law DSO DFC AE MA Cantab
150 Signed, Numbered and Certified
Robert Law was the Commanding Officer No 109 Squadron PFF from December 1944 through to September 1945. A member of the Cambridge University Air Squadron during 1938 to 1939, before being called up for war service in September 1939 as a flying instructor. He joined No 109 Squadron in February 1943 as a pilot and later became 'A' Flight Commander, and then the Commanding Officer from December 1944 through to August 1945. He later commanded RAF Little Staughton until its closure.