 Word that Lewis was developing his own solutions to the minimum range problem reached the AI team at St Athan some time in early 1940 . Bowen was extremely upset . He had become used to the way the researchers had been put into an ill @-@ advised attempt at production but now Rowe was directly removing them from the research effort as well . Tizard heard of the complaints and visited Dundee in an attempt to smooth them over , which evidently failed . On 29 March 1940 a memo from Watt 's DCD office announced a reorganization of the Airborne Group . Gerald Touch would move to the RAE to help develop production , installation and maintenance procedures for the Mk . IV , several other members would disperse to RAF airfields to help train the ground and air crews directly on the units , while the rest of the team , including Lovell and Hodgkin , would re @-@ join the main radar research teams in Dundee . Bowen was notably left out of the reorganization ; his involvement in AI ended . In late July , Bowen was invited to join the Tizard Mission , which left for the US in August 1940 . 
