Dave Reid, so true.
It was during a DC9 training session with a few F/O's doing touch and goes, we had a massive bird strike (a duck) on the RH windscreen on short final. Just red all over, blocking the instructor's view nearly completely. Stopped and turned off the active, and the instructor, armed with a load of toilet paper, opened the RH window to lean outside and started to clean up the mess.
Did not take long before he made a scream and came back inside, bleeding like h&ll from his RH wrist.
He had hit the safety wire of the wiper's axle.
Called it quits, we saw enough blood for that day
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