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RV-4 Canopy Conundrum

RogerH

Member
Long story short, I need some advice, input, help on replacing a canopy & frame.

I recently purchased Oly Olson's RV-4, successfully ferried it from St. Louis to SLC, UT with no issues, thoroughly enjoying the aircraft and it's capabilities along the way.

Yesterday 45 minutes into my first local flight, I hit a pretty substantial bit of turbulence and within about 30 seconds the canopy decided to detach and departed the plane, along with the canopy my glasses and headset also departed. Fortunately I was just 4-5 miles from my home airport at the time, NORDO, but squawked 7700, the training kicked in, and I got the plane on the runway without further damage.

I've advised the County Sheriff, airport personnel, fellow pilots, etc hoping the canopy, frame, and a Go-Pro camera are recovered...should make for some interesting video.

In the event, the original is lost for good, any chance someone might have a spare canopy frame & canopy for sale? I'm a pilot, not a builder so if that question is on the dumb-side, please be gentle...my hearing isn't quite what it was prior to the canopy departure. :(
 
Bummer. Glad you're OK, though. Don't give up on finding it. A friend once had a canopy depart a One Design; found it in a field, undamaged. One of my neighbors has an undamaged canopy off a Soviet fighter that someone found in his field.
 
Ditto on not giving up. I know an RV-4 builder who lost his canopy, found it, and reused the frame with a new bubble.

Dave
 
RV-4 CANOPY

''I hit a pretty substantial bit of turbulence ''

WOW, substantial it must have been, good job on getting the aircraft back on the ground..

Hoping you find your canopy and frame in one piece as I believe Oly had a Todd's dark canopy on his (yours) -4 and they are no longer available as far as I know.

I have 2 spare canopy frame in my hangar but it will be way too expensive to ship one to SLT.

Best of luck

Bruno
 
Yikes

Glad you are safe. As you get some time to think about what happened feel free to share if anything new details/updates come to mind.

Cost wise, this might be worth an insurance claim, no?

Sorry it happened, but glad you are safe.
 
Very nice job dealing with the emergency. Glad you and the a/c are safe.


One question please... there was a discussion here awhile back about whether a departing canopy would damage the tail. Was there any damage to the tail in your case? Horizontal or vertical? Did it even contact the tail?

Again, nice job! Since the 4s are primarily tilt-over canopies, I imagine this left you with no windscreen protection whatsoever. And, with your glasses gone possibly diminished eyesight as well. A true emergency.
 
Dark Canopy

Thanks Dave

Good to know if I ever (Hope not) need another one...:(

Bruno
 
Unfortunately the canopy did hit the right horizontal stabilizer causing a dent on the leading edge. It's not creased so I'm hoping I can pull it out rather than have to replace the sheet metal.

As to the failure mechanism, hopefully the assembly is located and there will clear sign of what happened; however, even then I may never know exactly. It was about 45 minutes into a local flight to another airport, 3-4 touch & go's and cruising about 1,000ft AGL fortunately close to my home airport when it released. I had just a few moments earlier hit some pretty rough turbulence so I'm speculating that may have been a contributing factor. The release happened incredibly fast. It peeled the rivets on the right side and the hinged arm that locks when the canopy is upright clean off.

It's hard to overstate the impact of going from a steady-state flying to the unprotected blast of air that resulted. It's quite a shock and now several days later I'm still dealing with the effects on my hearing.

I'll be following up with Van's and canopy sources tomorrow to see what my options are. I have zero experience in airplane building so needless to say I'm worried how long & what it's going to take to return to an airworthy state.

Additionally there is the lingering concern that without a clear understanding of how this happened all the repair effort could be for naught if it is a recurring event. A more secure method of locking that doesn't compromise safety in case of an emergency would be good. I understand how others have experienced similar situations on take-off but it seems odd it would have taken 45 minutes to release like it did ???????

Don't get me wrong, I enjoyed the performance of the RV-4 during my brief time flying it but this has been a hard introduction to the world of Experimental aircraft. :(
 
Is canopy loss a common thing with RV-4's?? It just happened to a friend of mine flying his newly purchased 4 from Wyoming to Alberta. He took off from Cut Bank and lost it over some farmland north of there. He tried finding it, so far no luck. It didn't do any damage to tail. He also lost his Bose headset and sunglasses and it got extremely WINDY!!

Phil
 
As this was just my first flight in the aircraft after the ferry flight from St. Louis to Salt Lake City I can't offer any insight.

I waswarned by the seller to make sure the canopy was properly locked and to the best of my recollection I did just that on the local flight.

Unfortunately I too lost some prescription glasses. I thought I lost the Bose headset as well but that was recovered from the passenger seat later on the ground. Doubt with the wind even if I could keep the headset on, anything I said would have been readable.

I'd appreciate you sending on the contact info for your friend, as we're in the same boat, well I should say airplane, maybe we can help each other through the experience.
 
I think you'll find consensus is: improperly latched. Not fully engaged in the first place, or handle inadvertently bumped closer to open.

Of course no one is going to admit to that :)

And definitely not me when I lost my RV-3 canopy during take-off. I blame the builder for not having a set of taxi position holes :)
(They are there now.)

I my case the canopy flipped open with the strap holding it at 90 degrees open. I tried to pull it shut, then remembered: fly the plane! Added power and strap broke, canopy flipped all the way open resting on the right wing, then tore off as it was designed to do. No noticeable damage to tail section. Scratched paint on top of wing where top of canopy rested.

Sorry if this is slightly off topic.

Finn
 
Freely admit in my case the cause may have been organic in nature, e.g. me.

Thinking that shoulder-harness stretching bit of turbulence just prior to release could have resulted in an inadvertent elbow to the locking lever, not a lot but just enough to set up the chain of events...heck if I know but that seems likely.

Either way, just want to come up with a replacement so I can get back in the air and enjoy the handling & performance of an RV-4, without spending all **** winter learning how and then fabricating the replacement canopy assembly. :confused:
 
Canopy Safety Latch

Hi Roger

You mentioned that you may have hit the canopy release lever (Normally mounted just forward of your left shoulder on the -4 ) when you hit turbulence ..

Did you have the RV-4 Canopy Safety Latch installed on your -4 (Oly could answer that if he's online)?? You could get one from Van's..pretty cheap insurance.

It is design to keep the lever closed via a spring maintaining pressure on the mechanism..

I know I don't have it on my -4 but have one handy and will install it as soon as the a/c is out of the paint shop..I came pretty close on a few occasion of hitting the lever with my elbow and that will not have been nice..

Best of luck

Bruno
 
I would think any of these tilt-over canopies that don't have a "lip" at the leading edge to tuck under, are prone to being accidentally jettisoned if the front pin latching mechanism is compromised for any reason. A friend had this happen on his DR107 One Design. All it takes is a little bit of wind to get under that leading edge and the transition from down force to lifting force, is instantaneous and can be extreme. At least that's how I see it. Sliding canopies that have a fixed windscreen to butt-up against are a different animal altogether.

The tilt/sliding canopy I'm designing for my Acroduster will have a 1.5 inch lip/fairing to slide under when closed for this exact reason.

The good news is that it sounds like from Roger's explanation and from the others, that if the canopy does depart and hits the tail it is likely to be only a glancing blow. Dealing with the aftermath of that however, is something else entirely. Again to the OP...nice work.
 
What I have seen

First off, Great job getting safely back on the ground..plane will be fixed!
I built my -4, so I fully understand the complexity of the canopy. i also inspect/maintain several other -4's (non-builders) and have found that many have been modified to what folks deem simpler or more comfortable. If built per plans, with the spring installed on the pin tube, and the secondary safety latch installed, I can assure you, it takes effort to open or deploy the canopy in flight. I have recently seen one with no springs or safety catch of any sort that flew open on start-up and severely damaged the frame. I know of others who put a small bungee chord on the latch to hold it aft/locked as a final checklist item. I installed a microswitch that will illuminate a bright red LED in my panel if mine isn't locked, although with the springs on the pin tubes, even unlocked my canopy isn't going to come open. It is literally a 2 handed operation to close/open the canopy. If haven't built a canopy, find someone in your area that can assist you...its one of the hardest parts of building a -4. I hope you can find your departed one and salvage some or all of it.
 
?Canopy down and locked - stripes aligned?

Sorry to hear about the mishap, and nice job getting the airplane back on the ground without incident!

When the USAF had issues with the canopy on the F-4, they added a striped tab behind the locking arm and a stripe on the arm itself. When the stripe on the arm was aligned with the stripe on the tab, the canopy was visually confirmed to be locked. I used electrical tape on the inside of my canopy skirt to make one stripe, and wrapped electrical tape around the locking rod to make another. The stripes align when the canopy is fully locked, providing a nice visual warm fuzzy the handle is fully aft and the canopy is properly latched. I also have the spring installed, making canopy operation a two-handed event. The only downside to the spring is that the pins ?default? to the closed and locked position causing some sheet metal scuffing when the canopy is inadvertently closed without physically holding the handle forward. The spring mechanism is highly effective keeping the pins fully extended fore and aft.

All the best,

Vac
 
Hendricks latch

I know people will say that this is overkill, but this is what we did with our latching mechanism. It has a safety lock that makes it virtually impossible to accidentally open in flight and we also added a switch that flashes a red light notifying the canopy is unlocked.
https://vimeo.com/116509137
 
Roger-I'm a transplant from NY to Ogden area and have built a RV-6 plus military maintenance background. I'd be willing to help you get the new canopy/tranparency fitted when your hearing returns. PM me if you want some help.

JB
 
A bit of advice.

If someone offers you a used canopy don't buy it. Each canopy is specific to the RV4 it was built to. To modify a used one may take you more time than building a new one. Also you probably won't get the same tight fit as one you built to your specific RV4.

Steve
 
Welcome to the club

I lost the canopy on my RV-4 about 7 years ago. Forgot to latch it. Many of us have forgotten to latch our RV canopy, the problem is in a 4 it is catastrophic. I ordered new parts from Van's and a new tinted canopy from Todds. It took me two weeks and 110 hours of labor to complete the installation. I agree with the earlier comment do not try to install a used one. The springs on the latch mechanism should be rigged such that you have to hold the latching handle open any time you are opening or closing the canopy. When you release your grip on the handle the spring should latch the canopy. Also, install a warning light on the panel connected to a micro switch that senses when the canopy is latched. I was in a climb and just as I leveled off at 1,000 ft it left the aircraft. I say it left but it was more like an explosion. I never found the canopy or the Garmin 396 that left with it.
 
Thanks to all!!!

Thanks to everyone who's commented, offered advice, and suggestions.

Felt pretty low after the canopy mishap and the positive support offered through the VAF forums helped get me over that. :) Working with the insurance company to develop a recovery plan that hopefully will my -4 airborne again quickly.

For sure, whether the original canopy assembly is found in a repairable state or if a new replacement is required, the locking mechanism will be configured with a much more robust design than the previous one.
 
If anyone is reading all this and thinking of adding a alarm or light to there -4 canopy here is what I did And it works great and is very simple.

Get a $3 hood switch off amazon or eBay. They are just a simple pin switch you can easily cut to adjust length. Mount the hood switch on the back canopy block in the baggage area with the pin going into the back of the block. Now when the canopy pin is engaged in the block it pushes the hood switch. I ran this input into Dynon and set a RPM warming limit so I get A loud announcement in the headset if the canopy is unlatched above 2,000rpm but no annoying warning while taxing with my canopy open for ventilation.
 
Pretty sure the Rocket is the same style latch. I didnt like the fact that closed was not a positive lock, so I modified mine to go over center. Same basic parts, just changed the geometry a bit.
 
Hoo-hoo!!! :)

My canopy has been found. A plea for help on a local SLC, UT TV station aviation classified-ad website (KSL.com) got the attention of a local helicopter pilot who volunteered to make a search of the area and sure enough found it this afternoon.

It's battered, bruised, in need of tender loving care & new plexi-glass but never-the-less this gives me a solid starting point for rebuilding & repairing versus a complete clean-sheet restart which was beyond my feeble skill set.

I promise to never speak ill of helicopter pilots ever again :D
 
Good eyes on that chopper pilot

Hoo-hoo!!! :)

My canopy has been found. A plea for help on a local SLC, UT TV station aviation classified-ad website (KSL.com) got the attention of a local helicopter pilot who volunteered to make a search of the area and sure enough found it this afternoon.

It's battered, bruised, in need of tender loving care & new plexi-glass but never-the-less this gives me a solid starting point for rebuilding & repairing versus a complete clean-sheet restart which was beyond my feeble skill set.

I promise to never speak ill of helicopter pilots ever again :D

There was an incident several years ago in Virginia.
The canopy was found by hunters years later and completely undamaged.

Daddyman
 
Canopy Safety Latch

In part as a progress post and also to pass on info to other potential RV-4 "newbies" such as myself, here's where things stand:

With the assistance of Old Republic Insurance I'm working with Loyd Remus in CO Springs to replace the canopy which was damaged beyond repair after ricocheting off the right horizontal stabilizer and falling 1,000ft. To complete the fabrication the aircraft is being transported to CO on a truck and will be flown back upon completion.

In the process of ordering parts for the canopy assembly from Van's I noticed on the Bill of Materials a "Canopy Safety Latch" which involves according to Van's assembly instructions "...safety catch that latches automatically when the canopy is closed. A steel catch is added to the canopy mechanism. It engages through a slot cut in the fuselage side rail and rides on a steel striker plate. A spring and bracket ensure that the latch engages."

Unfortunately on the RV-4 I purchased either the extra safety latch was not available from Van's during the 1985 build time-frame or the builder and later owners opted to not install it.

Either way a valuable lesson learned and needless to say, the safety latch will be installed as part of the rebuild process.

Also the replacement tinted canopy matching the old Todd's version was sourced through Aircraft Spruce in any one was curious about that.

Again a painful & expensive lesson learned but hopefully N-655BB will be airborne soon and headed back to it's SLC, UT hangar not much worse for the wear.
 
L39 AND EXTRA 300

In part as a progress post and also to pass on info to other potential RV-4 "newbies" such as myself, here's where things stand:

With the assistance of Old Republic Insurance I'm working with Loyd Remus in CO Springs to replace the canopy which was damaged beyond repair after ricocheting off the right horizontal stabilizer and falling 1,000ft. To complete the fabrication the aircraft is being transported to CO on a truck and will be flown back upon completion.

In the process of ordering parts for the canopy assembly from Van's I noticed on the Bill of Materials a "Canopy Safety Latch" which involves according to Van's assembly instructions "...safety catch that latches automatically when the canopy is closed. A steel catch is added to the canopy mechanism. It engages through a slot cut in the fuselage side rail and rides on a steel striker plate. A spring and bracket ensure that the latch engages."

Unfortunately on the RV-4 I purchased either the extra safety latch was not available from Van's during the 1985 build time-frame or the builder and later owners opted to not install it.

Either way a valuable lesson learned and needless to say, the safety latch will be installed as part of the rebuild process.

Also the replacement tinted canopy matching the old Todd's version was sourced through Aircraft Spruce in any one was curious about that.

Again a painful & expensive lesson learned but hopefully N-655BB will be airborne soon and headed back to it's SLC, UT hangar not much worse for the wear.

HAVE A LOOK HERE:
aQONtYjDlMw


There are also a good number of L39 videos that show a positive latched TEST before start up with a push above the head.
 
Yup, that's what I'm looking for. A positive "lock & loaded" no doubt about it, click & clack confirmation things are secure and not going anywhere. The canopy locking system spring on my RV-4 with no redundant lock left a lot to be desired.

Great video, I admire anyone that can pull that level of G's and appear to be relaxed and enjoying themselves in the process.

Thanks :)
 
I lost my canopy in the driveway when I first ran up the engine. Had t close but not locked and when I ran up the engine the lift opened the canopy and lfted it off in like 2 secconds. Luckily it didnt break and I was able to polish ot a couple scratches and re-attache it.

a) proved that the rivets holding the hinge in place would rip out if never needed.

2)makes me wonder how one could ever take off with canopy unlatched.

3) Made me add "check canopy latch" prior to rolling onto runway on checklist.

I have no "additional latch" on mine but have thought of adding from time to time.
 
Canopy closed and locked is in my checklist a couple times. Before i take off i always check one more time that handle is all the way back and i push on the canopy as an additional check.
 
Wow, that's scary. It's likely my biggest fear. I installed a canopy unsafe flashing red light that illuminates if the pin is more than 1/8th inch short of fully seated (well before the canopy would open). I'm sure most failures are on takeoff, as you say, due to not fully securing the canopy - this light should help me avoid that fate. I've always wondered whether it would rip off the plane. I think you're lucky it did - imagine trying to control with the canopy hanging off to one side or flapping around. Congratulations on the safe outcome - well done.
 
Same story happened too many moons ago locally... the canopy of the -4 opened right after take-off rotate, and fell on the right wing, remaining attached for the remainder of the flight. Pilot lost headset and prescription glasses but not the nerves, and brought the aircraft back to a safe landing.

Unfortunately that very -4 was lost to fire following maintenance inspection a couple of years later :eek:
 
What kept it attached? The per-plans pop rivets will 'unzip' as soon as the canopy goes open far enough to stress the ones at the front end of the hinge. I discovered that fact right after purchasing my 1st -4, when I was replacing the simple lanyard that kept it from going too far, but did nothing to keep it from slamming shut in a wind gust.

Charlie
 
I have inspected RV-4's that had screws in place of the rivets. I suspect this because the builder felt the pop rivets were substandard and didn't realize the zipper importance.
 
What kept it attached? The per-plans pop rivets will 'unzip' as soon as the canopy goes open far enough to stress the ones at the front end of the hinge. I discovered that fact right after purchasing my 1st -4, when I was replacing the simple lanyard that kept it from going too far, but did nothing to keep it from slamming shut in a wind gust.

Charlie

For that very reason I'd like to install a pneumatic door-closer (in addition to the Van's redundant safety latch when closed) on my rebuilt canopy. Has anyone had experience with a particular model of pneumatic or is it as simple as going to Home Depot and adding the hardware to the plane & canopy? If someone can offer a photo or two that would be great. Thanks
 
Charlie, don't remember how the canopy/fuse attachment was done, probably not with the as per plans pop rivets... nevertheless canopy stayed attached in this case, good or bad.
Don't recall of any comment about to how the -4 behaved with the right elevator/stabilizer probably blanked out...
 
What kept it attached? The per-plans pop rivets will 'unzip' as soon as the canopy goes open far enough to stress the ones at the front end of the hinge. I discovered that fact right after purchasing my 1st -4, when I was replacing the simple lanyard that kept it from going too far, but did nothing to keep it from slamming shut in a wind gust.

Charlie

Sequence in my RV-3B: Canopy opened 90 degrees, held by strap, then strap broke and opened 180 degrees and rested on right wing. I remembered "fly the airplane" and added throttle to safely make it around the pattern and land. It's very possible that had I been a cooler pilot and only used enough power to climb and fly the pattern near minimum required airspeed, the canopy would have stayed attached. It only tore off when adding full power and getting above maybe 100 mph.

Finn
 
Canopy Release

Roger, bummer on the first flight!
When I built my latch, I made sure it was a tight fit when the pin/ rod inserted into the nylon block. I still have to pull a second time to fully latch down. Something to consider when you build another is the extra safety latch lock.
I?d also join your closest EAA chapter that has some RV builders. That?s a resource that?s priceless.
 
RV-4 Canopy Strap Concern

My RV-4 is 90% done, 90% to go and I am working the canopy.

Question is, what to use for the canopy strap to keep canopy from opening all the way on the ground.

If the need arises to jettison the canopy in flight, seems tp me that a strap that is too strong, like paracord, may not break and the canopy would be dancing around on the right side of the aircraft.

Need something that will break when canopy departs but is strong enough to keep canopy open on the ground without breaking.

What are you folks using????

Bill Morelli - A&P I/A - EAA Tech Counselor
Up North Aviation
CNC Instrument Panel Fabrication
Web www.upnorthaviation.com
E-Mail [email protected]
- RV-4 build in progress !!!
 
My solution and thoughts.

I built my -4 as are you, and I have maintained and inspected many others. No two are alike. Everything from parachute chord to steel chains I have seen. Van did a great job of KISS, and the whole canopy jettison idea is great, however after I flew mine a few hours with a chute, I was pretty sure the conditions I (and a PAX) would need to be in for a bail out where far less a worry than keeping the canopy LATCHED in flight and keeping it open on the ground. I have the standard configuration latch mechanism per plans, along with the additional "knife blade" safety latch. I cant imagine any way to have an accidental blow off with this set-up. I also have a very bright LED on my panel with a micro switch that is illuminated if my latch handle is 1/32" off the latch position. For a hold open, I have a 10-12" gas strut simply connected to the canopy cross former and a simple bracket on the R/H roll bar weldment. It holds it exactly where i want it, dampens the close and isn't in the way. I have it attached with a single bolt and large area washer on each side. I'm certain either the strut would fail or the attachment would rip out in event of an in flight opening, but really no way to prove it. ..Hopefully, you will get yours done soon and join the "flying RV-4" group soon..they are a blast!
 
?.the canopy of the -4 opened right after take-off rotate, and fell on the right wing, remaining attached for the remainder of the flight. Pilot lost headset and prescription glasses but not the nerves, and brought the aircraft back to a safe landing?.

Sequence in my RV-3B: Canopy opened 90 degrees, held by strap, then strap broke and opened 180 degrees and rested on right wing. I remembered "fly the airplane" and added throttle to safely make it around the pattern and land. It's very possible that had I been a cooler pilot and only used enough power to climb and fly the pattern near minimum required airspeed, the canopy would have stayed attached. It only tore off when adding full power and getting above maybe 100 mph?.

Question - if the canopy can, if mounted more strongly, remain attached long enough to permit a landing, and if the airplane flies well enough for that, what?s the advantage in having it depart?

If it?s open and the lift force on the canopy will tend to hold it open, and if the airplane remains under control, that sounds better than having it leave. The pilot can still leave if he wants to parachute.

Dave
 
Stay attached

Yes, seems it makes sense to have a strong tip-over attachment.

However, at higher speeds I don't know if it could start ripping apart at the hinge and trash around held by the tip-over attachment.

Then why have the "weak" piano hinge riveting?

Perhaps the whole idea comes from fighter jets where you want to get rid of the canopy so you can eject. Not having ejection seats in the RVs, and having tip-over canopies that open widely enough for easy egress while in all flight conditions, that idea may be flawed.

Question would be if there are any uncontrolled flight conditions where the tip-over canopy would not stay open?

I forget, are there any actual cases of egress in flight with a parachute from RVs?

Or any reported flight conditions where the canopy did not stay open?

Without real world data, or some engineer doing computer simulations, I'm beginning to think it's all up in the air :)

Finn
 
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