My KR2 that had the canopy "issue" has a front hinged "pop up" canopy. The latch was (changed now) a central knob between the seats that pushed 2 rods, one on each side, through holes in tabs that are attached to the canopy. One of the things I disliked about it is that it was never easy to confirm that the canopy was decently latched. It popped open on the ground more than once.
On the day of the incident I had trouble latching the hatch, to the point where I shut down the engine, got out and looked at it. I finally sorted it out, or so I thought. When the hatch popped open in flight, somewhere between 160-180mph at around 1000 feet, the canopy lifted up to somewhere around 30-40 degrees. I struggled to reach it and it was VERY difficult to pull down, to the point where I was afraid the handle would break. I could not pull it all the way down. The effect of the canopy popping open was a severe pitch down, everything was ejected from the cockpit, maps, gps and even my headset. I had blue marks on my shoulders for weeks from the harness. Even full up elevator would not keep the nose up with the canopy open like that, I lost around 800 feet in the initiial dive, Only by cutting the throttle and pulling the canopy down as far as I could I was able to get the plane level again. The plane has a center stick so I had my right hand on the canopy handle and left on the stick. Because of this I could not reach the throttle (on the left) again, the engine was at idle and I still had to keep some up elevator for level flight. The result was that I could not reach the runway, when this happened I was approaching my home field after doing a few touch and goes at another field. I ended up landing short of the runway on soft ground. The landing gear dug in and the plane almost flipped. Tests later showed that even with the canopy latched the way it should be, flexing of the fuselage, like when you turn in your seat to reach for something behind you, could cause at least one side of the latch to pop open. I did reach behind me to look for a camera just before the canopy popped. If I was lower when it happened things would have been really bad! Rudi On Wed, Jan 25, 2023 at 3:34 AM John Gotschall via KRnet < [email protected]> wrote: > So does anyone know are the failures with canopy latches becoming > unlatched or are these something like frame failure, or delamination at the > plexiglass events? > Some mix of the above? > > Should my canopy construction include a carbon fiber or kevlar single > direction strip on the outside of the canopy from one rear latch, over the > top and down to the latch on the other side? > > I have flown 3 owned planes so far, one experimental, none had reliable > door/hatch latches but their forward hinges never failed and the relative > wind always held them closed. > > Is there a vacuum above a kr canopy in flight that makes it pop up? > > Thanks > -- > KRnet mailing list > [email protected] > https://list.krnet.org/mailman/listinfo/krnet >
-- KRnet mailing list [email protected] https://list.krnet.org/mailman/listinfo/krnet
