"Mitchell Holman" wrote in message
. ..

I have heard the additional motor made the plane unbearably loud.

https://www.youtube.com/watch?v=Jku2AE91LHU

Until the DC-3 came along, frequent fliers risked developing hearing loss.
In the case of the British, only the upper classes could afford to fly and
if they went deaf, the working class couldn't give a ****...