With greater speed comes canopy bulge. Over-complicated mechanical systems using many parts to stop the bulge are completely unnecessary. The chief design problem is how to get an anti-bulge pin on the canopy to seat into the fuselage since the path of motion of a descending canopy is curved. Pins don't slide into a curved slot...but an egg can! Affix half an egg to the bottom of the canopy. Drill out a round hole in the fuselage sill where the egg nests as the canopy closes. The nested egg prohibits the canopy from bulging. An anti-bulge system with NO moving parts! It's easy to design complicated Rube Goldberg contraptions but hard to get a design titrated down to only the necessary and sufficient elements to get the job done. You know you've succeeded in the design when it meets some standards: Does it work? Is it robust? Does it have a long service life? Is it least expensive in price and time to build? Is it simple? Is it beautiful. The egg anti-bulge system works efficiently, simply, reliably and well. It is robust to damage, doesn't hardly cost and builds quickly. Use a wooden "Easter Egg" which can be bought at almost any cutsie store. Ask your wife where to get one. Aircraft Spruce doesn't carry wooden eggs! Here's a solution: NO moving parts in this anti-bulge system. See my "Egg" album.