Canopy Release Mechanism - Alternate Design

Noah · #1 09-04-2008, 10:22 PM

View Video of Mechanism Operating

I roughed in this canopy release design tonite with a vertical actuation handle (removed one part of the Tee handle making it an "L". Note the extension spring to keep the pins engaged. I'm aware of the debate about using the canopy release in flight (not looking to rehash that again). I'd like to keep some form of release for maintenance and, more importantly, for emergency ground egress when parts might be crumpled.

I know some other guys (Davepar, Chad Jensen?) may have done something similar? Not sure these made the cut when avionics started going in though.

Do most radios extend past the subpanel? How about most EFIS'? Any other thoughts?

Mel · #2 09-05-2008, 06:34 AM

We've done quite a few like this. Works fine. Many radios go through the sub-panel, but they are to the right of the mechanism. Most EFIS are not that long.

Sam Buchanan · #3 09-05-2008, 07:21 AM

Quote:

Originally Posted by Noah

View Video of Mechanism Operating

I roughed in this canopy release design tonite with a vertical actuation handle (removed one part of the Tee handle making it an "L". Note the extension spring to keep the pins engaged. I'm aware of the debate about using the canopy release in flight (not looking to rehash that again). I'd like to keep some form of release for maintenance and, more importantly, for emergency ground egress when parts might be crumpled.

I know some other guys (Davepar, Chad Jensen?) may have done something similar? Not sure these made the cut when avionics started going in though.

Do most radios extend past the subpanel? How about most EFIS'? Any other thoughts?

Here is my version of the modified canopy release from 1999:

During the course of nine years of flying and 2 1/2 panel rebuilds I have never had a need to remove the canopy. If doing this again, I would leave out the canopy release so the space would be available for whatever avionics might go there. The release would be of no value in the aftermath of a crash.

cjensen · #4 09-05-2008, 07:42 AM

Yep, mine is modified like that. More like Sam's without the spring though. No problems with anything interfering yet...

Noah · #5 09-05-2008, 09:30 AM

Thanks for the input guys.

Sam, it's unclear what the arm connects to on the left side in this lo-res photo. Is there a spring keeping the pins engaged? What does that arm connect to??

For guys who didn't use a spring, how do you ensure that the thing doesn't open from vibration?

Sam Buchanan · #6 09-05-2008, 09:46 AM

Quote:

Originally Posted by Noah

Thanks for the input guys.

Sam, it's unclear what the arm connects to on the left side in this lo-res photo. Is there a spring keeping the pins engaged? What does that arm connect to??

For guys who didn't use a spring, how do you ensure that the thing doesn't open from vibration?

It's just a tab with a hole in it that can take a bolt, pin, circlip, or whatever to lock the mechanism. However, I don't think I ever put anything in the "lock" (been nine years....slept a couple of times since then....). There is enough friction in the canopy pins to hold everything tight especially when you consider aero loads on the canopy trying to lift it off the plane and the pressure exerted by the canopy locking mechanism. It takes a significant effort to turn the release handle when the canopy is closed.

cjensen · #7 09-05-2008, 10:01 AM

Quote:

Originally Posted by Sam Buchanan

It takes a significant effort to turn the release handle when the canopy is closed.

You got that right!!! I almost can't turn the thing with my hands when the top skin is in place...a pair of pliers makes it easier to turn, but it's not going to vibrate past the over-center "lock" on it's own, even without some sort of lock installed.