I remember reading somewhere (possibly one of Winkle Brown's books) that the Luftwaffe's WW2 tandem-engined Dornier 335 Pfiel was fitted with a compressed air-operated ejector seat. One of the design features required the pilot to manually jettison the canopy before ejecting. Unfortunately the two levers were attached to the canopy itself rather than the airframe and in a couple of cases dead pilots were found in the subsequent wreckage minus their arms, which had been wrenched off by the departing canopy.
Not a great morale-builder for the crews, especially considering that the ejection sequence required explosive charges to blow off the fin and aft propellor to prevent the seat from hitting them. Assuming they managed to keep their arms, a manual bail-out would probably have resulted in a very messy ending anyway.
Edit:
It was mentioned in Winkle Brown's
Wings of the Luftwaffe. I had a sniff around the Internet and some sources quote the arm losses during ejection as a tall story told to him in 1945 by a Luftwaffe pilot. Who knows!!!
Whatever, from a Hong Kong models thread on the Pfiel:
Post-war French tests of the ejection mechanism with the Do 335 M17 also showed it to be unsatisfactory. Apart from the issue with the canopy potentially hitting the pilot on release, the ejection procedure was also very complicated: the pilot first had to push three buttons in sequence to activate the explosive charges for top fin, prop, and lower fin; then pull both canopy handles to unlock and release the canopy; disconnect the microphone; arm the seat; assume the ejection posture with feet placed on the seat supports; and pull the ejection handle.