On the afternoon of 7 June 1942, one of its Rolls-Royce Merlin engines caught fire and led to the aircraft crashing near the England-Wales border, killing all eleven crew-members.Immediately thereafter, Philip Dee, B J O'Kane and Geoffrey Hensby visited the Aeroplane and Armament Experimental Establishment at Boscombe Down to examine the available aircraft and concluded that the Halifax had the best possibilities for mounting the scanner in different locations for testing.The TRE team replied that it would be better to place a few bombs on the target than a huge load in a field, but could not explain much beyond that as they were under orders not to give away any details of the system.It is not recorded what arguments may have occurred within the company, but the direction from Prime Minister Churchill giving H2S the highest national priority overrode any complaints.[6] On the weekend of 6 and 7 June, Lovell and the team met with Alan Blumlein and two of his associates from EMI to examine the system with an eye to beginning production.Shortly after, the left wing broke off and the aircraft rolled over and crashed in a field on the Courtfield estate in Lydbrook near Welsh Bicknor on the north side of the River Wye.[7] Due to the secret nature of the aircraft, for many years the only information available on the crash was a single index card at the Ministry of Defence that stated the accident occurred when the crew attempted to restart a failed engine which then set on fire.[8] The lack of detail led Blumlein's wife and Isaac Shoenberg, head of EMI's research division, to suspect sabotage.There were several design flaws with the early Halifax that also contributed to the crash; the fuel valves to the engines were on the wrong side of a fireproof bulkhead, as were the extinguisher bottles.