There was a joint US Army and UK Army exercise on Salisbury Plain in the mid sixties. I was there with my trusty Whirlwind Mk10 and the US Army were there with Hueys and CH37s.
We all went for a ride in each other aircraft and whilst I was poling this Mojave around it started to rain, quite heavily. Looking around I noticed the crewman with a big squeegee pushing rainwater down a hole in the middle of the floor. At ceiling level there was a continuous spray coming off the drive shafts going into the gearbox.
The front reminded me of a Bristol Frightener and it was just a draughty.