Interesting note in the MD 500 POH they specifically prohibit the use of Simple Green due to it's corrosive nature. try a soaping mix of Dove and water.

On Saturday, July 25, 2015 at 11:43:03 AM UTC-7, Walt Connelly wrote:
Any recommendations for washing the fabric on a Pawnee? I find myself
sitting around the time of year twiddling my fingers waiting to fly a
tow but rain, overcast.....you know the drill. I could be using my time
to make our tow planes shine........your recommendations please?

I know about Simple Green for Aircraft but I understand that is for
aircraft aluminum........

Walt Connelly




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Walt Connelly