Canopy opening in flight

Anyone know of an occurrence of a forward hinged canopy that opening in flight? Any possibility of this happening if the forward hinged canopy was unlocked on a flight?

Thanks Tom

Yes. A friend had his Silent F-H canopy unlock, but only noticed it when he was trying to figure out why he couldn’t penetrate as well as he remembered. At least in that model, there was no excessive noise or canopy vibration. Locking it appeared not to be a big issue and he continued the flight. Don’t recall how wide he said it opened, though it couldn’t have been much.

I got in a rush once and launched with the canopy unlocked on my Pegasus. It rattled a bit while on the runway, but smoothed out after liftoff. It never tried to lift, so I ignored it until after release. No problem locking it in flight.

Reinforced my use of a checklist. Also made me glad I got a glider with a forward hinged canopy. I know of at least two accidents involving side-hinged canopies, and one instance of the rear canopy on a G-103 blowing open and shattering while on tow with a solo pilot.

I know of a DG400 which had a canopy open in flight because it wasn’t locked. It did partially open as I believe the pilot’s headset was dangling outside after landing, but the pilot did manage a succesful landing. Happened at Marfa many years back.

On the ASH-25 it is possible to confuse the air vent with the forward canopy release (used for bail out when you pull both front & rear releases). If the forward release is pulled in flight the front leading edge of the canopy lifts about 1" and the instrument panel drops about 1". The rear bayonet fittings will hold the canopy in place. This happened to me once and I was able to temporarily resolve the problem by removing my dress belt and looping it under my leg and over the release knob. That held the canopy front down until I got the machine on the ground. I later realized that the incident occurred because I was mildly hypoxic and very stupid. After 3 hours above 10,000' I got cold and pulled the "air vent" shut . . .
ROY

Well...Â* I once forgot to lock the canopy of my LAK-17a before takeoff.Â*
Three hours and forty-five minutes into the flight I was casually
looking about the cockpit and noticed that it was unlocked.Â* I simply
moved the levers to the "locked" position and continued the flight.

On 8/26/2018 5:35 AM, Tom wrote:
Anyone know of an occurrence of a forward hinged canopy that opening in flight? Any possibility of this happening if the forward hinged canopy was unlocked on a flight?

Thanks Tom

--
Dan, 5J

If you have a lifting instrument panel on a forward hinged canopy, you might not notice until you land.

I saw an L-33 written off landing without spoilers because the pilot was holding the side opening canopy closed. He sideslipped it to a good position, but should have changed his hand to the spoiler handle by 50 ft.

Of course a sideslip to the hinge side would have kept the canopy down.

I once towed an ASW19 with an unlocked canopy, no dramas but
the glider pilot (post flight) described the canopy sucking partially
open then dropping before sucking partially open again. Using his
elbow he was able to temporarily secure it until we got to a height
that allowed him to release and put the canopy locks into the
appropriate place.

The additional (near) airprox with an R44 at about 400ft during
climbout was far more exciting!

At 11:35 26 August 2018, Tom wrote:
Anyone know of an occurrence of a forward hinged canopy that
opening in
flight? Any possibility of this happening if the forward hinged
canopy was
unlocked on a flight?

Thanks Tom

Dan Marotta wrote on 8/26/2018 8:23 AM:
Well...* I once forgot to lock the canopy of my LAK-17a before takeoff. Three
hours and forty-five minutes into the flight I was casually looking about the
cockpit and noticed that it was unlocked.* I simply moved the levers to the
"locked" position and continued the flight.

On 8/26/2018 5:35 AM, Tom wrote:
Anyone know of an occurrence of a forward hinged canopy that opening in flight?
Any possibility of this happening if the forward hinged canopy was unlocked on a
flight?


My recall of several incidents (other people's) is the unlocked front hinged
canopies stay in place until there is something that disturbs it, like turbulence,
negative G, perhaps a side slip. When disturbed, they can pop open momentarily,
but sometimes completely.

On Sunday, August 26, 2018 at 4:35:35 AM UTC-7, Tom wrote:
Anyone know of an occurrence of a forward hinged canopy that opening in flight? Any possibility of this happening if the forward hinged canopy was unlocked on a flight?

Thanks Tom

Definitely. DG canopies have a single locking pin which can't be closed in flight once unlocked. I have had this happen to me. Another local pilot had it happen in a DG400; a wind gust blew the canopy open and twisted sideways, bending the mechanism. You can't depend upon wind pressures keeping it closed.

Tom