Grob twin II rear canopy hinge release mechanism

[mas]

During flight, the right rear canopy lifted and the passenger used his hands to hold the canopy in the closed position for the rest of the flight (immediate descent). Upon post flight inspection, we noticed the rod has dropped and the lever handle is disconnected. Has this happened before to anyone? We are looking for drawings to see what is behind and how to gain access for the repair.
Any advice?

[Duster[_2_]]

Mas,
Yes, coincidentally we reported ours had what appears to be a similar problem with our Grob 103 III exactly one year ago today. Ours was a failure in a 1cm pin that holds the handle fitting with the "bayonet" rods that engage the receiver pin on the gunwale. I replaced the pin, but beware that this pin was worn through by friction with the handle plate. More info if you need.
Mike

From Duster 7-5-16: Our club Grob 103 Twin III canopy lock/unlock mechanism (front seat) failed on the ground when someone tried to open it. Upon close inspection, one of the 2 hidden bolts closest to the handle had gradually been cut through by the lever action to the breaking point. Though we found a way to replace the bolt, we may want to inspect the other bolts in both front and rear canopies. The problem is that the manufacturer glassed in both mechanisms and there does not seem to be a way to effect inspection other than to cut into the frames. Does anyone have a clue as to how to do this? Have there been reports of similar issues with these models? I can't seem to find any AD's on it.

Here are some pictures of the mechanism taken by a Grob owner in Sweden in 2007 of a damaged frame with a window cut out to make repairs:
http://syntaxsociety.se/~wed/flyg/progress.html

Thanks,
Mike

From JJ:
First off, you should report this to the Federallies. The canopy frame can be opened up by carefully cutting a hole in the problem area, then replace the worn / broken bolts, then close it up by gluing in a backing plate which can be a "donut" shape. After the backing plate cures, then glue in a skin replacement (which can be the original piece ) if you were careful when opening up the frame. Fill and paint and she's ready to go. If your not comfortable with any of this, your frame should probably see a sailplane Doctor..
Have fun,
JJ

From Duster:
Your suggestion to report this to the Feds is worth serious consideration, particularly since the locking mechanism cannot be inspected without cutting into the frame. The "catch 22" is a bit rhetorical; what would prompt anyone from creating a window to inspect the thing unless there was already a problem? An A/D? For each Grob of this type, there are 4 bolts to check for each of the 2 canopies. Not much of a problem on the ground, but if you wanted to egress at altitude, the unlocked left side may prevent bailout even though the right-side emergency release worked.
Good thoughts, Thanks.
Mike

[Duster[_2_]]

For a schematic see page 7 of the maint manual:
http://www.utahsoaring.org/Documents/N54554/N54554%20USA%20Twin%20II%20Maintenance%20Manual.pd f