I think its audio sourced as its just as noisy on one and performance doesn't change much
Megle2,
Haven't you heard of the acoustic lift theory for the Islanders.
When it goes quiet, the 'orrible thing quits flying.
<https://www.facebook.com/paravionft/posts/313631895413897>
Undaunted by technical realities, the design team at
Britten -
Norman has announced. ... An outstanding feature of
Islander technology has always been the ...
lift increases as the square of the noise, and as the
principle of
acoustic lift is ...
Tootle pip!!