This talk should perhaps begin with a brief reference to the initial development and research made by the Company into the helicopter as a crop spraying machine Many will remember the early experiments made by Dr W E RIPPER, using one of the original Sikorsky R4 helicopters These trials were made at Henley and Cambridge m the early part of 1945 The results were sufficiently encouraging to consider helicopter possibilities in this industry However, the flying limitations of the R4 helicopter did not allow a full investigation into operational and economical findings