Although promising in concept and successful in trials, the Rotodyne program was eventually cancelled when a combination of politics and lack of commercial orders arising from concerns over high levels of rotor tip-jet noise doomed the project.
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The one great criticism of the Rotodyne was the noise the tip jets made; however, the jets were only run at full power for a matter of minutes during departure and landing and, indeed, the test pilot Ron Gellatly made two flights over central London and several landings and departures at Battersea Heliport with no complaints being registered,[6] though John Farley, chief test pilot of the Hawker Siddeley Harrier later commented:
<blockquote> From two miles away it would stop a conversation. I mean, the noise of those little jets on the tips of the rotor was just indescribable. So what have we got? The noisiest hovering vehicle the world has yet come up with and you're going to stick it in the middle of a city</blockquote>
There was a noise-reduction programme in process which had managed to reduce the noise level from 113dB to the desired level of 96 dB from 600 ft (180 m) away, less than the noise made by a London Underground train, and at the time of cancellation, silencers were under development, which would have reduced the noise even further — with 95 dB at 200 ft "foreseen",[18] the limitation being the noise created by the rotor itself.[19] This effort, however, was insufficient for BEA who, as expressed by Chairman Sholto Douglas, "would not purchase an aircraft that could not be operated due to noise", and the airline refused to order the Rotodyne, which in turn led to the collapse of the project.
