[5] Conceived as a fighter station, this location would have suited interception of any aircraft attacking the northwest of the UK, and also defence against an enemy invasion from Ireland.The following year, three of its Whitleys were deployed to RAF Driffield to participate in the first "Thousand Bomber" raid on Cologne, Germany on the night of 30/31 May 1942, although one aircraft failed to return.The airfield was reactivated for private aircraft in 1969 in preparation for the Investiture of the Prince of Wales at nearby Caernarfon Castle and it was occasionally used from then on.[9] One notable tragic incident occurred at RAF Llandwrog on the 10 October 1943, when two Armstrong Whitworth Whitley medium bomber aircraft, (K7252 and K9041), collided.[5] Almost 71,000 bombs containing the nerve agent Tabun had been seized in Germany at the end of the war, and these were stored in the open at RAF Llandwrog, until 1954 when, in Operation Sandcastle, they were transported to Cairnryan for disposal aboard scuttled ships at sea, 120 miles (190 km) north-west of Ireland.The helicopters are leased and are operated on behalf of the charity by Babcock Mission Critical Services Onshore.This was an old gun turret fixed on the ground and the trainees fired from it at a large, wooden model aircraft, which was attached to a motorised truck, that ran on a narrow-gauge railway.Some disused airfields were considered for the task and RAF Llandwrog was finally chosen because of its remote location.[19] To enable the work to be done safely, twenty one Bellman hangars were erected on the three runways at RAF Llandwrog.In 1954 a plan to dispose of the Tabun was created, simply putting it aboard ships and sinking them in the Atlantic Ocean.[18] The 31 MU had used Glynrhonwy quarries near Llanberis, to hold the Tabun nerve gas before it was transferred to RAF Llandwrog.[22] The initiative came from the medical officer at RAF Llandwrog, Flight Lieutenant George Desmond Graham.The Royal Air Force Mountain Rescue Service started operations in May 1943, but due to the administrative lag of wartime, it was not officially promulgated until January 1944.357 Squadron RAF and was awarded a DSO for a daring rescue behind Japanese lines in Burma (Myanmar).Other parts of the site have been repurposed as workshops and small businesses, whilst many buildings remain largely untouched since the end of the war.