Preparing for emergency landings (canopy)

[N523RV]

I just finished reading the "I Learned about Flying From That" in the latest Flying magazine about an emergency water landing down in Mexico when the engine quit. It would appear that they did everything right and walked away from the accident alive. When I read these types of articles, I always try and ask myself how I would handle the same situation in the RV.

In this particular case, I got to thinking about how I would handle the "open your door before landing" checklist item. With more traditional aircraft having doors that open outward instead of upward this is a simple task but I wonder what the best option would be in an RV? This discussion could really go down two paths: slider vs. tip-up. In my case, tip-up.

With the tip-up we have two latches, the side latch and the top latch. A simple twist on the top latch and it will be ready. The side latch can also be unlatched easily and quickly. However, what happens if the canopy is unlatched during flight?? Will it stay down? Will it be forced open and blow off? Let's assume that it stays down in flight when unlatched, would it make sense to prop it open with the upper handle as we do when taxi'ng?? Would this cause the canopy to blow off then? How would we handle the situation differently between a terra-firma landing versus a water landing?

The slider RV's out there may have an easier decision to make? Just open the canopy and slide it back. If it rips off in flight, so be it? (Risk of taking out the tail feathers?) In a water landing this would immediately allow water in.. that a good thing? (The guys in this article had hard time opening the doors.)


I certainly don't have the answers and would love to hear what other RV'rs (especially the coastal RV'rs) think about such things. Not much chance of hitting water here in the Midwest but you never know.

 

[Captain Avgas]

The slider RV's out there may have an easier decision to make? Just open the canopy and slide it back. If it rips off in flight, so be it?

I doubt it would be that simple with a slider. Some people who have taken off with their slider canopies unlocked have reported that it is very difficult to slide the canopy either rearward or forward (to lock it) in flight. And even if you could slide the canopy back it would almost certainly come forward like a bullet when you hit the water and decelerated....and this might just take off the top of your head if there's any slack whatever in your seatbelt.

Come to think of it I would imagine that there'd be a better than even chance that an RV would flip in a ditching....and getting out of a slider or a tip-up could prove very challenging.

Does anyone know of a pilot who ditched an RV (slider or tip-up).... and survived to tell the tale.

 

[pierre smith]

No

The slider RV's out there may have an easier decision to make? Just open the canopy and slide it back. If it rips off in flight, so be it? .

Hi guys,
This has been discussed in the past and the consensus was that you can't open a slider in flight (which makes wearing a parachute a moot point).
Yes, the guys had a hard time opening the doors because of all the pressure. If they had a flooded cabin, the doors would open much easier since the pressure inside and outside would equalize.

If you were to make a water landing, it would definitely behoove you to have the canopy cracked ANY amount, allowing it to first flood for the above reasons.

Bear in mind that you probably would have tumbled at least once, depending on how slow you were at impact, and more than likely would be disoriented and shaken as Jimmy Buffet was when he went over in his seaplane. He remembered his training which reminded him of "Bubbles up", meaning to figure out which way is up by the bubbles' upward movement, probably saving his life or at least contributing to it. Dunno if this helps Can't hurt. This is one reason that I have an axe on board.
Regards,

 

[Mel]

If the tip-up canopy is unlatched in flight it will open about 4-8" and stay there. It has happened. Tony Bingelis had this happen on one of his first flights. The airplane flies fine, but he said he could not close it in flight.

 

[Ironflight]

Does anyone know of a pilot who ditched an RV (slider or tip-up).... and survived to tell the tale.

I am sure I read a story about a fellow who ditched his -8 out in Hawaii maybe two years ago (it was while I was building), and survived, but I can't remember where I saw it....


My plan for ditching would be to unlock the canopy and pull the "pip" pins that connect my forward canopy rollers to the canopy frames. That would make it much easier to get rid of the canopy after splashdown.

I know many people came here from the Grumman world, and probably remember the endless discussions about what to do with the canopy in these cases. Many carried a 6" piece of PVC pipe with a slot cut in it lengthwise. The idea was you'd unlock the canopy, slide it back, and put the "canopy blocker" on the rail to keep the thing from slamming shut.

I'm pretty sure that you'd never get the -8's canopy to slide back enough in flight to make this worthwhile.


Paul

 

[n5lp]

If the tip-up canopy is unlatched in flight it will open about 4-8" and stay there. It has happened. Tony Bingelis had this happen on one of his first flights. The airplane flies fine, but you cannon close it in flight.

I had my tip-up come open in flight once and it was a non-issue and I was able to close it with no problem after slowing down quite a bit. The secondary latch held, but I think I opened it also to help in closing the canopy.

 

[Low Pass]

The -8 will tend to move toward a 1" open position. Now the question is what happens after it gets about 3-4" open?? Might slide back violently.

Couple of points which have been pretty well hammered in the archives I believe.

To get out while in the air, it is possible to get it (-8 slider) open in reasonably controlled flight. Has been done at least once.

If it goes upside down in the water you might get it open, but jettisoning the lid sounds better. On the ground, it isn't going to happen. I've seen an -8 on it's back and, as expected, it sits squarely on the bubble.

One question is whether the bubble offers significant protection between touching down and stopping versus using quick release pins and jettisoning the bubble before landing. Anyone in the back seat is going to have very little protection without it. Another argument for the fastback!

Don't forget about the increased liability of flying around with quick release pins holding the canopy. I haven't used quick release pins in mine, but am now thinking I might change. I fly over a lot of water.

 

[G-force]

Perhaps for those routinly flying over water, a SCUBA Spare Air setup might be prudent? Would give you at least time to flood the inverted cockpit and open or bust out the canopy. Not any bigger than your typical hand held fire extinguisher.
http://www.snorkelingequipment.com/eshop/10Expand.asp?ProductCode=4061

 

[pierre smith]

Yes

Thanks Mike.......close to what the Unlimited Hydro guys use drag racing at well over 220 MPH. I've seen several lose it, go inverted and keep breathing until help arrives or they extricate themselves.

Regards,

 

[Vern]

Canopy-opened for crash landing

Years ago my instructor was flying a Navion when an oil line broke, followed by an engine failure, covering the windscreen with oil. He opened the sliding canopy and loosened his seatbelt, alternating between sticking his head up to see and sitting down to fly. Just as he sat down, he touched down and the heavy canopy snapped closed.

Had his head been up, he would have been severely injured.

 

[Howie]

The article Paul refers to is here (home page) in the "Articles" section under Flying.
"Honolulu Center I'm at ....."
Reminds me to wear my helmet and inflatable vest.
H

 

[G-force]

Thanks Mike.......close to what the Unlimited Hydro guys use drag racing at well over 220 MPH. I've seen several lose it, go inverted and keep breathing until help arrives or they extricate themselves.

Regards,

Exactaly. My day job is building offshore powerboats, and all canopy'ed race boats have onboard air systems. Many drivers will also have a spare air as well. Every racer as well has to go in the "dunk tank", a cockpit simulator that we dunk inverted in a pool and they have to get out. The key is maintain composure, not to panic, and let the cockpit flood before expending energy to open the hatch.

 

[rv7boy]

It's interesting that no one has discussed Van's design for the tip-up which includes an emergency release pin for the forward hinge. ( I haven't gotten that far on my RV-7 so I assume it's still in the plans for the 6,7 and 9 tip-ups.) However, I know a lot of 6,7, or 9 builders who have omitted the handle protruding through the instrument panel. Of course, I'm not sure I would have enough wits about me under water to know how to pull that handle.
Don

 

[flybill7]

It's interesting that no one has discussed Van's design for the tip-up which includes an emergency release pin for the forward hinge. ( I haven't gotten that far on my RV-7 so I assume it's still in the plans for the 6,7 and 9 tip-ups.) However, I know a lot of 6,7, or 9 builders who have omitted the handle protruding through the instrument panel. Of course, I'm not sure I would have enough wits about me under water to know how to pull that handle.
Don

I guess the tip-up forward pin release would come in handy if you were in a mishap and the canopy was jammed and wouldn't open with the normal latch release mechanism. Even with the forward pin release, you still have the gas-struts that would prevent canopy from releasing completely. A pexiglass busting device as a third option probably isn't a bad idea.

 

[gmcjetpilot]

"good Luck we are all counting on you"

RV's tend to flip over with off field landings so regardless have some gear to break, cut, pound, pry and bend (pliers) in case you need it.

As far as latch unlock before touch down, that's a PIC decision. I think having the tip-up closed gives some more roll over strength? Sliders are hard to impossible to open in flight, as I'm told, not withstanding optional builder installed pull-pins in the fwd rollers. Good luck you'll need it.

PS: if there's engine fire and smoke, opening a slider canopy could draw smoke/flames into the cockpit. The tragic Oregon RV-8 accident showed that.

 

[rv969wf]

Fire and Slider questions

PS: if there's engine fire and smoke, opening a slider canopy could draw smoke/flames into the cockpit. The tragic Oregon RV-8 accident showed that.

[/QUOTE]

Question about engine fire? Does anyone know which is best to help put an engine fire out? Hi Speed dive indicating 180k or slow down to say 55k ???? Of course one would want to shut the fuel an master off.

I talked to VAN's about 3 yrs ago about flying with the slider open to see if it is OK or NOT. They told me they never tried it. Hummm...Reason I asked them was because a friend of mine in a slider -6 was wanting to enter a flour drop contest where you throw a small bag of flour out and try to hit the middle of a circle. From what I'm hearing on VAF and other pilots is the fact that the slider can't be opened in flight. I've never tried it in flight and probably won't unless I do have a forced landing and I would hope to get it open slowed down to stall speed. Has anyone tried this, slow up to stall speed and try to open it. My -6 slider has a lever that latches in the side rail so I can taxi with the slider open only 6" and I thought about flying around the pattern at 65k and see what happened but I have not and probably will not because no one can answer the question. My thought was seeing the dang thing fly off and hit the rudder If someone has done this or trys it let everyone know. I wish VAN's would try this or put an RV in a windtunnel and test these things. AJ

 

[Mel]

The gas struts are indeed a big concern on the tip-ups. I have never installed them and never will. I installed my canopy release as per plans with the original "hold up" rod. I added a second "hold up" rod on the right side for windy conditions. When the canopy is closed, these are not connected so the canopy could be jettissoned if needed. I hope I never need it in flight. It is a VERY handy feature for working behind the panel in the shop. As a matter of fact right now I am replacing my panel and the canopy is sitting in the corner completely out of the way.

 

[kentb]

Mel;
How do you hold the canopy open without the struts?

Everyone;

I would think that opening either canopy type on an off airport landing would weaken the strength of the structure over your head. Granted that the impact damage may bend the release and not allow it to work and also you may end up on your back, I don't think that the release or the tipup jettison feature should be realized on to exit the aircraft.

The best strategy would be to carry a plexi cracking tools. That said, I need to put one in my plane that I can get to quickly.

Kent

 

[n5lp]

...
How do you hold the canopy open without the struts?...

I won't presume to answer for Mel but here is a quote from his post "I installed my canopy release as per plans with the original "hold up" rod. I added a second "hold up" rod on the right side for windy conditions." This is just a short folding rod that you use to prop the canopy up. Was in the original RV-6.

 

[Mel]

Thanks, Larry!

 

[Bad Sheila]

Canopy Open Problems

Have AN RV6. Canopy came open in flight. Could close the rear latch but not the side latch.
WARNING: When landing my stall speed was increased by 10-12 kts. Luckily I have the Skyview AOA with audible warning. Imagine my surprise when I was slowing to 60 kts for landing and the stall warning horn was screaming at me. YOU HAVE BEEN WARNED!

 

[sailvi767]

Something does not seem right with seeing a 10 to 12 knot increase in stall speed. That really should not happen with the canopy partially open. I am wondering if there might be a pitot static issue in your aircraft. Perhaps the canopy being open caused a pressure change in the cockpit leading to a false airspeed indication. A 20% increase in stall speed is just not plausible with a canopy open a few inches or even missing for that matter.

George

 

[Bill Boyd]

I've had it happen

Took off with tip-up canopy unlocked and only able to pull down enough to get the secondary latch holding it. Completed the flight and landed normally with the canopy thus ajar, and it was a normal flare and normal landing at customary speeds (65 MIAS over the numbers and 50 at the touchdown).

I suspect you have a static issue somewhere.

-Stormy 6-A

 

[ijustwannafly]

RV's tend to flip over with off field landings so regardless have some gear to break, cut, pound, pry and bend (pliers) in case you need it.

As far as latch unlock before touch down, that's a PIC decision. I think having the tip-up closed gives some more roll over strength? Sliders are hard to impossible to open in flight, as I'm told, not withstanding optional builder installed pull-pins in the fwd rollers. Good luck you'll need it.

PS: if there's engine fire and smoke, opening a slider canopy could draw smoke/flames into the cockpit. The tragic Oregon RV-8 accident showed that.

What accident do you speak of?
This is a very concerning subject for me. Its probably one of my biggest fears. After flying airplanes with doors like everyone else here most likely started in, going to a canopy style airplane adds a new fear to landing poorly, flipping the airplane, or as you guys are discussing a forced water landing.

Let me ask you this. I am somewhat perplexed over the fact that the general consensus is that it is hard to get a slider open in flight or a tip up down in flight.
That is counter intuitive to what most people would think.
The rushing air should all but blow the slider back and or push the tip up down into place.
Can someone explain this more please?
Thanks

 

[lr172]

What accident do you speak of?
This is a very concerning subject for me. Its probably one of my biggest fears. After flying airplanes with doors like everyone else here most likely started in, going to a canopy style airplane adds a new fear to landing poorly, flipping the airplane, or as you guys are discussing a forced water landing.

Let me ask you this. I am somewhat perplexed over the fact that the general consensus is that it is hard to get a slider open in flight or a tip up down in flight.
That is counter intuitive to what most people would think.
The rushing air should all but blow the slider back and or push the tip up down into place.
Can someone explain this more please?
Thanks

Seems somewhat intuitive to me. Opening the canopy will allow air into the cabin at a high velocity (think sticking your hand out of the car window at 80 MPH. Now imagine doing it at 150 MPH). Pressure will be exerted on every surface, including the canopy, as the air cannot exit. This pressure would lift the canopy and place a good deal of force on the sliding mechanism. I don't have a slider, but am guessing that this upward force causes enough friction to prevent movement. The sliding mechanism should be designed to eliminate friction at a downward trajectory (from gravity) and not likely for an upward trajectory.

Larry

Larry

 

[cfiidon]

Seems somewhat intuitive to me. Opening the canopy will allow air into the cabin at a high velocity (think sticking your hand out of the car window at 80 MPH. Now imagine doing it at 150 MPH). Pressure will be exerted on every surface, including the canopy, as the air cannot exit. This pressure would lift the canopy and place a good deal of force on the sliding mechanism. I don't have a slider, but am guessing that this upward force causes enough friction to prevent movement. The sliding mechanism should be designed to eliminate friction at a downward trajectory (from gravity) and not likely for an upward trajectory.

Larry

Larry

I believe you need to consider the venturi effect. When you open the canopy slightly, you are allowing high speed air to flow over the openings (at the canopy bow and around the sides), creating a very low pressure inside the canopy itself, or relative high pressure outside the canopy. To use your car window analogy, cracking the windows a little bit sucks air out. Open them enough and the air blows in also.
I imagine the same thing occurs with the canopy. Open a little and it's trying to close itself. At some point the venturi effect will reduce and the pressures will "balance". Past some point the canopy will probably try to blow off.
Where is that point? I'm sure a wind tunnel test could find it, or a very brave test pilot.

Don

 

[LettersFromFlyoverCountry]

I didn't put the quick release mechanism in (well, actually, I took it out early) because I didn't want to cut into the top skin to allow the hinges to pop out.

I've thought about this a lot and while I carry a plexi busting thing, I'm pretty sure that one the cabin fills with water, I wouldn't be able to swing it through the water with enough force to do much damage. I just don't know.

At the same time, I can see the plane flipping over in a foot of water and be unable to get out.

So I've thought this idea: What about smashing the canopy BEFORE you ditch?

 

[dhc2jeep1]

I, too, am wondering why it is difficult to open a slider canopy in flight. Please don't get me wrong, I am not doubting anyone's experience. I just wonder what is different between a RV slider and an AT-6 slider? I took some aerobatic training in a AT-6 and was instructed on the ground that in case I started to feel sick, to let the instructor know and we would open the canopy to the first notch for some fresh air. At the end of the first hour, I did start feeling sick and we opened the canopy to the first notch. It was not overly easy, but it also was not impossible either. I was also taught that if we had to bail out, we would open the canopy all the way and then jump out toward the wing. This makes me think about all the WWII pilots that jumped out of fighters with sliders too.

 

[rvbuilder2002]

Have AN RV6. Canopy came open in flight. Could close the rear latch but not the side latch.
WARNING: When landing my stall speed was increased by 10-12 kts. Luckily I have the Skyview AOA with audible warning. Imagine my surprise when I was slowing to 60 kts for landing and the stall warning horn was screaming at me. YOU HAVE BEEN WARNED!

Bad Sheila
Here is a warning back to you... I think it is highly likely that you have a leak in your static system that was influenced by a large pressure change inside the fuselage with the canopy open.

As far as why RV canopies open or can't be opened... it is at least partially caused by a varied distribution of aerodynamic pressure...

The shape of an RV canopy results in high pressure (on the outside) at the base of the windshield and at the aft portion where the canopy or rear window is interfacing to the top of the aft fuselage. There is low pressure in the zone of the high point in the canopy (above your head), just like a wing airfoil.
Depending on the canopy type (slider or tip-up) the delta between these pressures will cause different results.
I.E., a tip up lifts at the back because there is low pressure at the back of the moving portion of the canopy. A slider is difficult to open because there is high pressure pushing down on the aft end, resisting the lifting it needs to do during the start of the opening process.
There are likely other influences as well... such as friction in the rollers and slides on a slider induced by the pressure loads, etc.

 

[RKellogg]

Slider open in flight - Thorp T211

I used to give instruction in Thorp T211s, a low wing with sliding canopy similar in configuration to an RV, but a tad chunkier and slower. We used to open and close the sliding canopy in flight. Effort was not more than one person could manage easily. The Thorp canopy rolled fore/aft on a straight / horizontal rail system, and it didn't close nearly as cleanly as an RV. The open canopy cost about 10 knots in speed, IIRC.

The POH forbade landings with the canopy open, perhaps because the canopy could roll shut, perhaps due to tail blanking at high AOA...??

Someplace out in an Illinois cornfield there is a camouflage BDU cap that I lost while demonstrating the canopy procedure to an Air Force Colonel/ B-52 pilot. (Had a great time, Warren!)

- Roger

 

[RKellogg]

Static leak??

Bad Sheila
I think it is highly likely that you have a leak in your static system that was influenced by a large pressure change inside the fuselage with the canopy open.

Easy check : Do the static source instruments respond to abruptly opening/closing cockpit vents while in flight? When I have the in-cockpit alternate static source open, the altimeter and ASI show very direct response to vent changes (on the order of 10 kt or so). Opening a fresh air vent slightly pressurizes the cockpit and decreases indicated airspeed and reported altitude.

it is not entirely inconceivable that a partially open canopy would disturb the airflow at the static ports and cause the reported error.

- Roger

 

[ijustwannafly]

I believe you need to consider the venturi effect. When you open the canopy slightly, you are allowing high speed air to flow over the openings (at the canopy bow and around the sides), creating a very low pressure inside the canopy itself, or relative high pressure outside the canopy. To use your car window analogy, cracking the windows a little bit sucks air out. Open them enough and the air blows in also.
I imagine the same thing occurs with the canopy. Open a little and it's trying to close itself. At some point the venturi effect will reduce and the pressures will "balance". Past some point the canopy will probably try to blow off.
Where is that point? I'm sure a wind tunnel test could find it, or a very brave test pilot.

Don

Thanks Don
This is precisely what i was referring to.

 

[6S4 Hugo]

I am sure I read a story about a fellow who ditched his -8 out in Hawaii maybe two years ago (it was while I was building), and survived, but I can't remember where I saw it....

http://archives.starbulletin.com/2004/01/19/news/story1.html

"After impact the canopy closed and the aircraft inverted underwater, trapping me in the cockpit," Justman said in a written statement. "I released my shoulder harness and seat belt and worked at opening the canopy while underwater for over a minute."

"Miraculously, the canopy partially opened ... and I was able to eject myself from the cockpit just before the aircraft sank," he said.