Narrative:

Took off on a VFR flight and climbed to 7500 ft. Was flying over a low overcast when I noticed the right canopy latch was in the vertical position instead of full forward (the locked position). I tried to push it forward, but it was jammed. Since I was above the overcast, I proceeded to ZZZ and my speed was 210 mph TAS. I started a 400 FPM letdown at about 225 mph about 35 mi out. I then had scattered cumulus with tops at +/-9000 ft, base +/-4500 ft. After reaching 1500 ft MSL, I noted a thundershower on the airport, so I slowed to 135 mph and loitered 2-4 mi west of the field when the canopy came off. This is an isolated area. The shower moved off and I made a normal landing and secured the aircraft. Later, I worked with the left canopy to try to see what caused the problem. To open the canopy, you turn the keyed lock forward and the latch handle aft. If you turn keyed lock aft when the latch handle is aft, you may turn the latch handle forward, but meet resistance when it is vertical. But I found I could push it fully forward with some extra force. I also found it was locked full forward. I got in the plane (after opening and resetting the lock with the latch handle aft) and pulled the canopy down and pushed the latch handle forward. I met a little resistance at the mid point, but really had no problem pushing it full forward. I think the lack of resistance may be because this door has been operated more than the right, and the lift pattern could have been a factor. Here is what I believe caused the problem. I recall opening both canopies. I left the key in the right door while loading some baggage. I let the door down and then turned the lock left (aft), removed the key, and pushed the latch handle forward, but did not note the stoppage at the mid point. (It has always seemed abnormal to me to turn the key to the right (forward) to unlock and the latch aft.) solutions: 1) have a more detailed checklist and use it carefully. 2) fix the lock so it turns aft to unlock. Should a person inadvertently turn both locks the wrong way, he/she will be locked in. The canopies cannot be opened from the inside (there is no way to use a key inside, it will only let someone outside unlock, then open the door. Perhaps an inside/outside lock could be used.) nor outside without a key. You can readily see how one could perish in this situation. 3) the keyed lock should only lock the outside handle. The latching handle should always be moveable from the inside. Callback conversation with reporter revealed the following information: reporter stated that the canopy lock and latching mechanism is original equipment supplied from the kit manufacturer. Reporter advised that he may have left the right canopy latch in the vertical position before takeoff. Reporter stated that he has made up a detailed checklist to ensure that this does not happen. Reporter stated that he has sent a copy of his ASRS report to the aircraft kit manufacturer.

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Original NASA ASRS Text

Title: EXPERIMENTAL GLASAIR SUPER IIS LOSES CANOPY SECTION INFLT DUE TO IMPROPER POSITIONING OF LATCHING MECHANISM.

Narrative: TOOK OFF ON A VFR FLT AND CLBED TO 7500 FT. WAS FLYING OVER A LOW OVCST WHEN I NOTICED THE R CANOPY LATCH WAS IN THE VERT POS INSTEAD OF FULL FORWARD (THE LOCKED POS). I TRIED TO PUSH IT FORWARD, BUT IT WAS JAMMED. SINCE I WAS ABOVE THE OVCST, I PROCEEDED TO ZZZ AND MY SPD WAS 210 MPH TAS. I STARTED A 400 FPM LETDOWN AT ABOUT 225 MPH ABOUT 35 MI OUT. I THEN HAD SCATTERED CUMULUS WITH TOPS AT +/-9000 FT, BASE +/-4500 FT. AFTER REACHING 1500 FT MSL, I NOTED A THUNDERSHOWER ON THE ARPT, SO I SLOWED TO 135 MPH AND LOITERED 2-4 MI W OF THE FIELD WHEN THE CANOPY CAME OFF. THIS IS AN ISOLATED AREA. THE SHOWER MOVED OFF AND I MADE A NORMAL LNDG AND SECURED THE ACFT. LATER, I WORKED WITH THE L CANOPY TO TRY TO SEE WHAT CAUSED THE PROB. TO OPEN THE CANOPY, YOU TURN THE KEYED LOCK FORWARD AND THE LATCH HANDLE AFT. IF YOU TURN KEYED LOCK AFT WHEN THE LATCH HANDLE IS AFT, YOU MAY TURN THE LATCH HANDLE FORWARD, BUT MEET RESISTANCE WHEN IT IS VERT. BUT I FOUND I COULD PUSH IT FULLY FORWARD WITH SOME EXTRA FORCE. I ALSO FOUND IT WAS LOCKED FULL FORWARD. I GOT IN THE PLANE (AFTER OPENING AND RESETTING THE LOCK WITH THE LATCH HANDLE AFT) AND PULLED THE CANOPY DOWN AND PUSHED THE LATCH HANDLE FORWARD. I MET A LITTLE RESISTANCE AT THE MID POINT, BUT REALLY HAD NO PROB PUSHING IT FULL FORWARD. I THINK THE LACK OF RESISTANCE MAY BE BECAUSE THIS DOOR HAS BEEN OPERATED MORE THAN THE R, AND THE LIFT PATTERN COULD HAVE BEEN A FACTOR. HERE IS WHAT I BELIEVE CAUSED THE PROB. I RECALL OPENING BOTH CANOPIES. I LEFT THE KEY IN THE R DOOR WHILE LOADING SOME BAGGAGE. I LET THE DOOR DOWN AND THEN TURNED THE LOCK L (AFT), REMOVED THE KEY, AND PUSHED THE LATCH HANDLE FORWARD, BUT DID NOT NOTE THE STOPPAGE AT THE MID POINT. (IT HAS ALWAYS SEEMED ABNORMAL TO ME TO TURN THE KEY TO THE R (FORWARD) TO UNLOCK AND THE LATCH AFT.) SOLUTIONS: 1) HAVE A MORE DETAILED CHKLIST AND USE IT CAREFULLY. 2) FIX THE LOCK SO IT TURNS AFT TO UNLOCK. SHOULD A PERSON INADVERTENTLY TURN BOTH LOCKS THE WRONG WAY, HE/SHE WILL BE LOCKED IN. THE CANOPIES CANNOT BE OPENED FROM THE INSIDE (THERE IS NO WAY TO USE A KEY INSIDE, IT WILL ONLY LET SOMEONE OUTSIDE UNLOCK, THEN OPEN THE DOOR. PERHAPS AN INSIDE/OUTSIDE LOCK COULD BE USED.) NOR OUTSIDE WITHOUT A KEY. YOU CAN READILY SEE HOW ONE COULD PERISH IN THIS SIT. 3) THE KEYED LOCK SHOULD ONLY LOCK THE OUTSIDE HANDLE. THE LATCHING HANDLE SHOULD ALWAYS BE MOVEABLE FROM THE INSIDE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT THE CANOPY LOCK AND LATCHING MECHANISM IS ORIGINAL EQUIP SUPPLIED FROM THE KIT MANUFACTURER. RPTR ADVISED THAT HE MAY HAVE LEFT THE R CANOPY LATCH IN THE VERT POS BEFORE TKOF. RPTR STATED THAT HE HAS MADE UP A DETAILED CHKLIST TO ENSURE THAT THIS DOES NOT HAPPEN. RPTR STATED THAT HE HAS SENT A COPY OF HIS ASRS RPT TO THE ACFT KIT MANUFACTURER.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.