No. 76 Operational Training Unit RAF (76 OTU) was a Royal Air Force operational training unit during the Second World War. The unit was formed at RAF Aqir on 1 October 1943. Throughout its existence it was equipped with Vickers Wellington bombers - Mk. III and Mk. Xs (by October 1944 all the aircraft were Mk. Xs) and trained crews for night bombing operations with RAF squadrons in the Middle East. The Mk. X was the last of the bomber variants and the most numerous. It was generally similar to the Mk. III, but had the more powerful Hercules VI or XVI engine with downdraught carburettor. It can be distinguished externally from the earlier marks by the carburettor intake placed on top of the engine cowling – as in the photo from the IWM collection.