[B-Binns]

Guys: quick question. I had wondered about this previously, but had never posted. But some of the responses to DR's safety letter made me want to get an actual answer. Why do I never hear about builders of RVs installing an Emergency Release Canopy. I'm sure it requires a fair amount of re-design from what comes standard with the kits, but with so many really talented builders / designers / structural trouble-shooters . . . I'm surprised the option of an (ERC) for the RV series has not been created . . . most other aerobatic aircraft, whether advanced or just trainers have them (or emergency release doors, if not canopies), so why not the RV-series??? Thanks in advance.

 

[kevinh]

I did a 'fairly quick' release canopy. For my slider canopy I can pull the two pins holding the canopy to the track and then open the latch and I'm sure it will be gone shortly thereafter ;-).

The pins replace the standard AN3 bolts that connect the wheel assembly to the frame.

 

[Mel]

Actually the RV-6 has had an emergency canopy jettison feature as part of the standard kit from the beginning. Just because people choose not to install it doesn't mean it doesn't exist.
Of course since the addition of "struts", it isn't really practical anymore.
I don't like the struts and I DO like my canopy release, so mine is one of the few still around.

 

[DCat22]

Of course since the addition of "struts", it isn't really practical anymore.

Side note...as I was learning how to take the doors off the Remos GX a few weeks ago, I noticed the struts they use have a semi-quick release. ie. you pull back a little wire tab keeper and the strut ends pop right off the ball. I think if you pulled hard they would just come off without pulling the release.

Something I was going to look more into when I got that far, along with changing the release handle a bit -- so I could have a strutted tip-up without a big bar on the panel middle, but still with a canopy eject option. (In theory.) Pull both struts off with both hands at once, twist handle, and go -- and have the struts more likely to disconnect in the event you don't do it first.

Just talking outloud of course...I'm not even building yet.

 

[lancef53]

Does the tail survive the jettison? Does it matter at that point? Has there been many times a plane was abandoned?

 

[panhandler1956]

Ditto

I did a 'fairly quick' release canopy. For my slider canopy I can pull the two pins holding the canopy to the track and then open the latch and I'm sure it will be gone shortly thereafter ;-).

The pins replace the standard AN3 bolts that connect the wheel assembly to the frame.

I have an -8 with the exact same setup.

 

[D-Dubya]

Jettison?

Lance, we asked one of the guys at Van's that very question a few years back. At the time, we were debating whether or not to put the canopy jettison T-handle on a couple of tip-up canopy RV-7s we were building. They said that to their knowledge, nobody had ever jettisoned a tip-up canopy in flight.

Now for my two cents... The struts would likely break away after they caught the air stream, assuming that the "gooseneck" hinge arms were able to come up out of their hinged positions. The skin is going to try to keep those arms down. Properly motivated , one could probably shove the tip-up canopy rear edge up and back until the wind would get up under the canopy and pull the whole thing off. Of course, this is all conjecture on my part.

Like so many other things, you just need to do what you feel comfortable with.

 

[N941WR]

As someone who did a test flight with his tip-up unlocked, I would imagine that you could get out in flight, if you had to. The canopy floats open about 2 to 4 inches and if you slowed the plane down, you could push it open enough.

As for the goose necks, if you want the canopy to come off in flight, you are supposed to cut some slots in top skins, over the goose necks. A little tape will keep rain out.

As for the struts, if the wind got under the front of the canopy, those things are just going to pull out just before the canopy hits the VS.

The bigger question is, why isn't there a way to open the tip-up from the outside? The standard setup has the latch on the left side and the overhead twist handle. While a rescuer could get the side latch open, there is no way to turn the twist handle.

 

[Sam Buchanan]

Lance, we asked one of the guys at Van's that very question a few years back. At the time, we were debating whether or not to put the canopy jettison T-handle on a couple of tip-up canopy RV-7s we were building. They said that to their knowledge, nobody had ever jettisoned a tip-up canopy in flight.

Now for my two cents... The struts would likely break away after they caught the air stream, assuming that the "gooseneck" hinge arms were able to come up out of their hinged positions. The skin is going to try to keep those arms down. Properly motivated , one could probably shove the tip-up canopy rear edge up and back until the wind would get up under the canopy and pull the whole thing off. Of course, this is all conjecture on my part.

Like so many other things, you just need to do what you feel comfortable with.

I don't think you would ever get the tipup canopy open far enough to leave the plane. I've taken off with the canopy unlatched and once it gets into its slipstream position about 4" inches open, it is extremely difficult to move. It is possible to move it a bit easier if the plane is slowed to flap speed, but what are the chances we could do that in emergency conditions so dire somebody wants to leave the aircraft?

 

[Jamie]

I don't think the struts are the factor limiting the ability to jettison the tip-up canopies. A swift pull on the struts removes the strut from the canopy and/or canopy deck. It would just need to be a checklist item before bailing out.

 

[sprucemoose]

As the builder/ owner of a tip-up 6 (built without the jettison handle) I often think about this. My own conclusion, based on well over a decade of following RV accidents and just plain common sense, is that there is no good reason to wear a parachute in a tip up 6 or 7. While you may theoretically be able to get the canopy open enough to bail out in a controlled, slow-flight situation, the reality is that in the type of event that would inspire one to bail out would render the aircraft uncontrollable to the extent that bailing out would be physically impossible.

As a small data point, consider the recent history of the T-34. Several years back there was a rash of structural failure accidents which led to emergency FAA action limiting this aircraft to basically non-aerobatic, normal category operations. In the couple of years leading up to this action, there were three accidents involving structural failure of the aircraft, all of which were involved with mock aerial combat/ fantasy flight type operations. All three accidents involved 2 pilots on board. All six wore parachutes. All six rode the crippled aircraft to the ground and their deaths, obviously not by choice.

It is my firm belief that the requirement to wear a parachute for aerobatics is, like so many things in aviation, a case of "we've always done it this way, so we need to keep doing it this way." A hold over from the days of open-cockpit, prone-to-engine-failure aircraft. The same reason that the FAA manuals still recommend that you make a forced emergency landing in a farm field rather than on the road next to it, another old saw that may have been sound advice when we were all flying surplus Jennies but wholly obsolete in the modern world.

 

[jrs14855]

chute

The T34 accidents are a good example against chutes. I believe that the T34 wings folded up over the canopy, OR the structural failure was so violent as to incapacitate the pilots. Chutes are mostly good for inflight fires, control failures or spins gone bad. The best chance of bailing out is probably in a biplane.

 

[B-Binns]

Real world canopy release example

Hey guys: Thanks for all the responses. The reason I first asked the question about the existence of real emergency release canopies in the RV series was because when I first got my licenses I did a fair amount of basic aerobatic training. I trained at a school called Hart Air at Long Beach airport in Socal. They had several aircraft for aerobatic training: Extra 300, Pitts, Robin Sport. The school was extremely well run, aircraft well maintained, qualified aerobatic instructors, etc. I trained for a total of about 45-50 hours in the Robin Sport 2160 (low wing - metal - emergency release slider canopy), because it was the most modestly priced. Good, solid aircraft / heck of a lot of fun. The hard-deck for all maneuvers was 3,000 agl. I was impressed by how essential the 3000' hard-deck was because if you had a critical problem occur on the downside of a loop, split-s, etc. it was obvious and always emphasized by my instructor that you really only would have maybe several seconds to "get out." Several years after I completed my training, a guy from my circle of friends was doing some flying there. He and his instructor became pretty good friends and they went out one day for a fun flight: they had a problem (don't know if it was structural failure, or some type of critical control jam, because the accident occured in the Palos Verde Practice area over the ocean just off the Socal coast. Aircraft not recovered) The instructor called for ejection, they pulled the release handle and they both "got out". My friend survived and was rescued by the Coast Guard, the instructor did not. I don't know the specifics of the instructor's fatality (partial chute deployment or maybe he was hit by part of the airframe on initial emergency exit). I am writing this because my friend really experienced an event that most of us only end up thinking about when considering safety margins. They both wore chutes, in a certified aerobatic trainer, above a 3000' hard deck, with an emergency release canopy. It just shows that even with all safety measures observed, sometimes thinks still go very bad . . . one lived / one did not, but they both at least had a solid fighting chance because of the emergency release canopy. Thanks for Mel's response advising that, at least for the RV-6, the emergency canopy option may be available.