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  #1  
Old 11-08-2015, 04:17 PM
yankee-flyer yankee-flyer is offline
 
Join Date: Jun 2009
Location: Dayton, OH
Posts: 838
Default Canopy Opening/Prop Strike

Pasted in below is my copy of the incident report submitted to my insurance company. Hopefully it will be of some help if anyone has a similar problem. Yes, I am well aware of what I could have/ should have done. I've been through those 2 seconds MANY times. I had the canopy pop open during my second or third PAP flight 5 years ago but that was at cruise conditions and 2500 feet and was a non-event-- other than scaring me at least half to death. I really believe if I'd had another 10 or 15 feet of altitude this might have been the same.

Yes, I plan to install the canopy warning system-- can someone tell me just how that works? It is really necessary to leave the canopy up on the latch handle during long taxies in the summer, and I don't want an alarm scaring my passengers. What I'd REALLY like is a better latch system. preferably one that secures the canopy to the side rail.

Got my fire suit on

Wayne 120241/143WM 351.5 hours/5 years


INCIDENT REPORT
30 October 2015
RV-12 N143WM

On this date I was conducting a local area VFR flight with the intent of burning off fuel in preparation for the annual Condition Inspection I planned to begin the next day. I shot touch and go landings at Greene County Regional, my home airport, Dayton-Wright Brothers airport, and Moraine Airpark (I73) before making a full stop landing at I73. After talking with friends for a while, I began departure from I73 intending to return to I19. Checklist and run-up were normal. Takeoff was made with takeoff trim set and the recommended 1 notch of flaps.
Almost immediately after lift-off the canopy popped open an estimated 8-12 inches? it varied with airspeed. Wind blast knocked my hat off, taking my headset and glasses with it. The aircraft pitched down, there was a loud BANG, and rebounded into the air. I regained control, reduced airspeed to 50-55 knots, and continued to climb. I continued to an open area West of I73 and found that at 1 notch of and 55 knots or less I could pull the canopy back down to get the latch bar under the rollover bar but could not latch it because the sides had spread due to air loads and the canopy pins would not go into their slots. Experimentation showed the airplane was stable and controllable with no apparent problems at 55 KIAS.
Returning back East (I19 is East of I73) I saw a truck drive out to the runway intersection where I?d hit, Circling I73 there was no radio call so I assumed that there was no damage and returned to I19 (10-minute flight at 55 KIAS). Flew a normal pattern (at lower speed) and landed at minimum speed, holding the nose off as long as possible. When the nose dropped it became obvious there was no nosewheel. The prop did not strike the ground and the engine continued to run until shut down. I had no problem remaining on the runway. Inspection showed the nosewheel was gone (recovered later at I73), the fork had folded at the lower bend, and there was about 1/16 inch ground off one prop tip and just slightly more off the other. There were no prop marks on the runway at I19 bet there were at I73. Inspection of the nosewheel fork showed that the welds broke, allowing it to separate from the fork

I have a Master?s in AeroSpace Engineering and spent 37 years as an aircraft design specialist in the Conceptual Design Group ay Wright-Patterson AFB. This is what I believe happened. It is possible that the canopy latch was not completely engaged. It WAS engaged enough to prevent air coming into the cabin (Cool day!) and enough to keep the canopy from rattling during engine runup, mag check, and takeoff run. When the canopy opened, the latch handle sheared the heads off three rivets in the bottom of the roll bar and damaged another. The airplane was trimmed for takeoff and had just lifted off. In those conditions the stabilator is exerting a large downward force to maintain pitch-up angle of attack with the increased wing pitching moment with one notch of flaps. With the canopy up 8-10 inches I believe the airflow over the tail was sufficiently disturbed to reduce the effectiveness of the stabilator and cause the aircraft to pitch down, resulting in nose-first impact with the runway, followed my main gear hitting, then rebounding,at which point I was able to counter the pitch-down force until I was able to almost completely close the canopy.
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  #2  
Old 11-08-2015, 04:35 PM
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tomkk tomkk is offline
 
Join Date: Apr 2014
Location: Port Orange, Fl
Posts: 931
Default

Sorry you had this problem. The canopy warning system is just a microswitch at the canopy latch, adjusted to close when the latch is completely closed. The result is a open/closed indication on Skyview. No audio warnings.
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  #3  
Old 11-08-2015, 05:14 PM
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MartySantic MartySantic is offline
 
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Location: Davenport, IA
Posts: 1,392
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Wayne....

Sorry for the incident, but, happy you provided a detailed description of the event. Thanks for sharing. Hope you are able to make the needed repairs and back flying in short order.

Lifting off with the canopy not fully latched is eye opening. Has happened to me once and to this day say the words loudly before advancing the throttle, "flaps, trim set, canopy". Suggest ALL to do the same.

As many have said, FLY the AIRPLANE no matter what transpires.
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  #4  
Old 11-08-2015, 05:55 PM
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RVTrumpet RVTrumpet is offline
 
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Location: Hillsboro, OR
Posts: 63
Default

Quote:
Originally Posted by tomkk View Post
Sorry you had this problem. The canopy warning system is just a microswitch at the canopy latch, adjusted to close when the latch is completely closed. The result is a open/closed indication on Skyview. No audio warnings.
At least with the current SkyView software, if the switch is not fully engaged the SkyView will generate the audio warning "Check Canopy Latch" when the rpm is increased through 3700 rpm. The visual warning on the SkyView indicates the state of the switch; red for disengaged and green for engaged.
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  #5  
Old 11-08-2015, 06:42 PM
Mich48041 Mich48041 is offline
 
Join Date: Apr 2008
Location: Riley TWP MI
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I took off once with the canopy open. I posted about it HERE. My RV-12 did not pitch up or down. I do not remember but most likely did not have flaps deployed.
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Last edited by Mich48041 : 11-08-2015 at 09:04 PM. Reason: added "or down"
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  #6  
Old 11-08-2015, 06:57 PM
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tomkk tomkk is offline
 
Join Date: Apr 2014
Location: Port Orange, Fl
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Quote:
Originally Posted by RVTrumpet View Post
At least with the current SkyView software, if the switch is not fully engaged the SkyView will generate the audio warning "Check Canopy Latch" when the rpm is increased through 3700 rpm. The visual warning on the SkyView indicates the state of the switch; red for disengaged and green for engaged.
Ahhh, you're right, I forgot about that ...
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Port Orange, Fl
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RV-12 N121TK ELSA #120845; first flight 06/10/2015; 700 hrs as of 02/2020
RV-12 N918EN ELSA #120995 Eagles Nest Project; first flight 05/18/2019
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  #7  
Old 11-08-2015, 08:47 PM
yankee-flyer yankee-flyer is offline
 
Join Date: Jun 2009
Location: Dayton, OH
Posts: 838
Default I've got the earlier D-180

Does the latch warning work with that?

The airplane pitched DOWN, not up.

THANKS all

Wayne
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  #8  
Old 11-08-2015, 08:51 PM
RFSchaller RFSchaller is offline
 
Join Date: Oct 2010
Location: Phoenix, AZ
Posts: 3,168
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I have taken off once in my Cherokee with the door unlatched. It was just embarrassing. Thankfully I haven't missed the canopy latch yet, but like retract pilots there are those who have landed gear up and those who will. Sorry about your bad luck, but thanks for posting to remind the rest of us.

Rich
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  #9  
Old 11-08-2015, 09:41 PM
Mich48041 Mich48041 is offline
 
Join Date: Apr 2008
Location: Riley TWP MI
Posts: 3,237
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Quote:
I've got the earlier D-180. Does the latch warning work with that?
The short answer is no. You could re-purpose the spar warning input or else install the HS34 which has 4 more contact inputs. The big problem is to make the alarm dependent on engine RPM. The SkyView has that feature in its software, but the D-180 does not. If the canopy switch is connected to a D-180 input, the alarm would be on whenever the canopy is open, regardless of RPM. The pilot will soon get used to seeing the warning on and ignore it.
An early RV-12 builder ( 2johns on VansAirforce) wired a canopy switch and throttle position switch in series. The throttle switch should not operate until the throttle is pushed in beyond a certain point. The alarm should only sound when the canopy is open AND the throttle is shoved in.
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  #10  
Old 11-09-2015, 05:54 AM
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f1rocket f1rocket is offline
 
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Location: Martinsville, IN
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You can add me to the group that took off without the canopy latched. It also opened just after lift off. I did not have any flaps deployed but the airplane did not change in pitch as I recall. Are you sure you weren't startled enough when the event happened that you might have nudged the stick forward a little bit?

Just FYI on my event, I got distracted with a problem during run up and forgot it. This was BEFORE I installed the canopy warning system. Just at lift off the canopy popped open a couple of inches. I immediately grabbed the handle and flew the pattern back to landing. (I live on a short field) I could not close the canopy in flight.

If you have not done so already, I highly recommend installing the warning system. It's not an easy install but worth it IMO.
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