Harold Bleksley joined the RAF as far back as 1934 and initially trained as a wireless operator/navigator at the Electrical and Wireless School at Cranwell but later trained as a pilot. He served for a time in Singapore in the late 1930's before a posting back to the and to 220 Squadron in October 1939.
On the night of Sunday, 11th February 1940, three Hudson's took off from Thornaby for Ops to Heligoland, an area of sea off the German coastline. This was a cold night and snow was already covering the hills in the area. The lead Hudson, N7294, failed to gain enough height on take off, probably due to the effects of icing conditions on the aircraft's wings. It flew very low over Great Ayton and crashed into the first piece of high ground it came to on the North Yorkshire Moors. Having flown into the moor, just below a stone wall, it travelled up through the wall and then onto the hill top near to Captain Cooks Monument, above Great Ayton. It was thought the pilot pulled the nose of the aircraft up just before impact which avoided a complete nose-on impact with the side of the hill. The crash ripped the underside of the aircraft off and it ploughed it's way across the snow covered moor for a short before coming to rest in a small wood on its side. One witness, contacted in 2002, recalled one wing being broken off and the remaining wing being attached to the main fuselage, this wing was left sticking up in the air. Of the four crew on board, sadly three were killed but the gunner survived and was not seriously injured.