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Van's Canopy Latch Safety Switch

We used a PTT switch to do the same job.

If I remember correctly, to save on the wiring, the interior flood light ground was taken to a local earth and the now redundant wire was taken to the SkyView from the canopy latch switch.

One green/red SkyView widget for canopy locked/open completed the job. Works a treat.
 
For those with the D-180, Van's new switch or similar could be wired in series with the magnetic spar reed switches.

Before every take-off, I say out loud..... TRIM, FLAPS, CANOPY.

You can guess why I am in this habit! :eek: :eek:
 
For those with the D-180, Van's new switch or similar could be wired in series with the magnetic spar reed switches.

Before every take-off, I say out loud..... TRIM, FLAPS, CANOPY.

You can guess why I am in this habit! :eek: :eek:

I like Marty's idea better than another EFIS alarm that replaces pilot vigilance.
 
Not much info, does this mean when you feed a little throttle to taxi, the alarm will go off (which would make it worthless in my opinion)? Is it throttle position or RPM that sounds the alarm?
 
Not much info, does this mean when you feed a little throttle to taxi, the alarm will go off (which would make it worthless in my opinion)? Is it throttle position or RPM that sounds the alarm?

RPM

The standard configuration from Van's (you can choose to set yours how ever you want) will be to have the trigger RPM just below 4000 (run up RPM).
This way you can do all taxiing with the canopy open, and no alarm. When you do your run-up at 4000 RPM, the alarm should sound as a cross check of the system and as another reminder that the canopy is still open.

The reason for the system being offered is the unacceptably high level of crashes that resulted from the pilot taking off with the canopy unlatched or not properly/fully latched.

Some type of check list used every time would probably have prevent these accidents (even a very simple one like Marty's though I recommend at least a simple list stuck to the panel to help over come the occasional distraction that can foil a memorized checklist).
Not becoming distracted and simply "Fly the Airplane" would have prevented them also.

It seems that some pilots do not do either.....
 
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Thanks, that is what I needed to know, I think I like it that way. I am old and get distracted easily it seems, and that is one thing I do not want to ever miss.
 
CTAF
C-Canopy
T-Trim
A-Altitude
F-Flaps/Fuel Selector/Fuel Pressure/Frequency

Just before t/o.
 
Back in my gliding days we used:

CB SIFT CB

Controls
Ballast

Straps
Instruments
Flaps
Trim

Canopy
Brakes

It sort of translates for powered flying machines using ballast to equal any of the ballast on board - passenger, baggage and fuel.
 
... The reason for the system being offered is the unacceptably high level of crashes that resulted from the pilot taking off with the canopy unlatched or not properly/fully latched. ...

Just out of academic curiosity, what are the flight characteristics (or lack thereof) with trying to fly with the canopy unlatched?
 
I had a situation where the canopy was not fully latched. The handle caught on the white plastic piece along the rear of the hold down clip and the handle wedged between the plastic and the aluminum clip. Looked like it was latched but it wasn't.

This became apparent with the increased wind noise after liftoff. I unlocked the canopy and tried to lock the canopy in flight but could not move the canopy aft enough to get it to fully latch. I simply landed and fixed it.

The canopy will not open in flight but it will not move much either. The noise and wind is very noticeable but shouldn't distract you from flying the airplane. The handling was not changed as far as I could tell.

I like the idea of the switch and will add it soon.
 
It must be very quiet with the canopy closed for their to be a noticeable difference once it's open. In the 152 you can't tell when a door pops open - it's always like riding a motorcycle at 100mph in that plane.
 
I just received the kit yesterday. I'm not at the point where I'll be mounting it yet but as long as I needed to put in an order for some stuff I thought I'd get it.

Here's a picture of what's in the kit.

Bob

Canopy+Switch+Kit.jpg
 
Curiouser and curiouser

Someone stated earlier that it looked like you could liberate one of the wires for the cablin light, such that there would be no need to string another wire...if that's the case, it looks like this kit is made for those without the lighting option... If a new dedicated wire needs to be strung...ugh. AND it looks like you replace the latch and the UHMW...I'm awaiting arrival also so I can see what's involved. We have had one (uneventful) case of canopy-unlatched takeoff and go-around, so this seems a reasonably helpful fix.

Ah--just saw the Notification with all the instructions on Van's website--answers most all the questions...ugh still....
 
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New POH/FTS

The installation instructions reference an updated POH and FTS, but it appears they are not yet on the Van's website--latest are dated 2013.
 
Guess I'll ask

Is this approved by Van's as part of a ESLA build or do we need to add it to the list of things to be added after certification and fly off time? Any one know for sure?
 
If it is an option from Vans, it is covered and you do not have to wait until after sign off.
 
My DAR required that I provide a list of service notices and that I sign it indicating that I had complied with each notice. I consider any email from Van's with the subject, "NOTIFY", as being a service notice. I think that it is likely that a DAR or FED will require the canopy switch before an airworthiness certificate is issued. After all, this is a safety issue. At least 2, maybe more, RV-12s have crashed because the pilot was distracted by an open canopy. Common sense says to install the switch, regardless of any bureaucratic interpretation of the rules.
Joe Gores
 
Flight with canopy unlatched

I had the canopy come partly open on an early flight-- wasn't fully latched and it popped up to the detent position with the arm catching on the canopy frame-- about 4" up. I tried to pull it back down and couldn't, so I slowed to 80 KIAS, proceeded to the nearest airport, landed uneventfully, latched it and took off again. No big deal and no reason to lose control.

Wayne 120241/143WM
 
My DAR required that I provide a list of service notices and that I sign it indicating that I had complied with each notice. I consider any email from Van's with the subject, "NOTIFY", as being a service notice. I think that it is likely that a DAR or FED will require the canopy switch before an airworthiness certificate is issued. After all, this is a safety issue. At least 2, maybe more, RV-12s have crashed because the pilot was distracted by an open canopy. Common sense says to install the switch, regardless of any bureaucratic interpretation of the rules.
Joe Gores

Sigh....I agree....and ordered one. My never-ending build continues.
 
To install this, Van's provides a Skyview settings AND UPDATE file all together. This file will have the additional widget in it to recognize the new discrete input from this switch, and combine it with an AND statement about RPM being>3700 to annunciate the alarm. In addition, the standard Vans RV12 EMS layout screens will have the new visual element added to them.

Well, I have customized my EMS screens and do not want to overwrite them, as loading this file will do!

The solution though, is simple. If someone who is using the standard EMS screens installs the switch and updates their system using the file, then simply do a system backup file AFTER THAT to your USB drive. This creates a *.DFG file - but it is actually a simple text file. It is simple to read the text file and figure out how to duplicate the function by building the element directly in Skyview. (I did a lot of this in customizing my EMS screens.) For example, from the instructions saying to use EMS pin 12, the canopy switch is coming into the Skyview using General Purpose Input #8.

So if someone will make available their DFG backup file AFTER the install, we can duplicate it without building the logic element from scratch.
 
Trick to getting wire up through rollbar

Feed string through hole where canopy light wires come out of rollbar (enough to make it out large hole near fuse.....stick garage vac hose to large hole. You will have string @ vac hose in a sec....secure wire to string and pull through to canopy light wiring exit hole. EASY WAY!
 
Of Course!

Wow, thanks Ric, I spent all of yesterday getting the wire from behind the Dynon panel to the bottom of the roll bar. Am going to tackle getting it up to the top of the roll bar today, & I had forgotten the vacuum cleaner method. ( I had used that method months ago to get draw string/ wires through the control sticks). So thanks a million, it will make today's tasks much easier.. Cheers, DEAN
 
success, but..

Hi Ric & fellow builders , it wasn't quite that easy, but I did manage to get a draw string through eventually. Because the cross section of the roll bar is much larger than the control sticks, the speed of the airflow is slower (some may say not enough suck!) After many tries with string, I had success with very fine fishing line, with a piece of foam tied to the end, - the foam was compressed to get it through the little hole, then it expanded inside the rollbar & it was sucked through. It was also necessary to tape up all the other holes in the rollbar. This method may still be superior to trying to feed tiewire or thick fishing line through, as per Vans instructions.. Hope this helps those coming after, Cheers, DEAN...
 
Hi Ric & fellow builders , it wasn't quite that easy, but I did manage to get a draw string through eventually. Because the cross section of the roll bar is much larger than the control sticks, the speed of the airflow is slower (some may say not enough suck!) After many tries with string, I had success with very fine fishing line, with a piece of foam tied to the end, - the foam was compressed to get it through the little hole, then it expanded inside the rollbar & it was sucked through. It was also necessary to tape up all the other holes in the rollbar. This method may still be superior to trying to feed tiewire or thick fishing line through, as per Vans instructions.. Hope this helps those coming after, Cheers, DEAN...

Yup....you need a major "sucking vac". My wife bought me a $450.00:eek: garage/shop vac for Xmas....it sucks:D
 
Are you forgetting the tube?

Hi Ric & fellow builders , it wasn't quite that easy, but I did manage to get a draw string through eventually. Because the cross section of the roll bar is much larger than the control sticks, the speed of the airflow is slower (some may say not enough suck!) After many tries with string, I had success with very fine fishing line, with a piece of foam tied to the end, - the foam was compressed to get it through the little hole, then it expanded inside the rollbar & it was sucked through. It was also necessary to tape up all the other holes in the rollbar. This method may still be superior to trying to feed tiewire or thick fishing line through, as per Vans instructions.. Hope this helps those coming after, Cheers, DEAN...

It sorda sounds like you aren't feeding the new wire down the plastic tube that the lighting wires are fed through??? Just feeding it through the roll bar??? It looks like, from the contents of the kit, they might be assuming you don't have the canopy lighting installed, so a length of the plastic tube is included. I'm not to concerned that not running the wire through the plastic tube will ruin some vast eternal plan, but the plans do have you running the wire through the tube. For me, it took a few tries, but I was able to shove a length of safety wire through the tube and pull the new wire through. (a little boelube on the wires helped)
 
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I fed the white wire into the plastic tube first, and then pulled/pushed both tube and wire up into the roll bar using some plastic coated garden tie wire to do the pulling. The tie wire went down the roll bar through the hole in the top fairly easily. Lots of different ways of doing this.
 
plastic tube

Hi Bob, yes you are right, I had not previously installed the tube & Cockpit light as I intend to operate strictly day VFR. However as I now have to get the wire up through the rollbar for the Canopy Safety Switch I decided to install the cockpit light anyway. Today's job will be to get the tube up there, then the wires through it. Good fun, as always! Cheers, DEAN...
 
After painstakingly pulling the 2 canopy light wires to panel and looking for the connections - Vans just confirmed the WH-L435 (YEL/PRP) referenced on 31B-15 Step 8 the same as the WH-L80 (YEL/PRP) referenced on 40-12 step 18 and the WH-L436 (YEL/GRN) referenced on 31B-15 Step 8 the same as the WH-L82 (YEL/GRN) referenced on 40-12 step 19 so there was no need to fish them up to the panel they were sitting just under the rollbar. They will be updating page 40.
 
One hot day I took off with an unlatched canopy. My first reaction was to reach for the canopy handle. But then I remembered reading about a plane that crashed while the pilot was trying to close the canopy. So I let go of the handle and flew the plane. Other than being a little windy inside, the plane flew just fine. In fact, the plane might be a little more aerodynamic because the canopy settles in a position of least resistance, about 6" open. I climbed to a safe altitude, then raised the nose to slow the plane, and then managed to get the canopy partly latched so that it was not so windy inside. Then I landed and latched the canopy. The biggest detrimental affect was to my ego. :D
 
Thank you Joe. It's nice when others are willing to share their experiences for the educational benefit of their fellow pilots. As I gain more experience in the
-12 I'll reciprocate.

George
 
In regard to "the unacceptably high level of crashes that resulted from the pilot taking off with the canopy unlatched or not properly/fully latched.", what exactly are the aerodynamic effects of an unlatched RV-12 canopy? I assume there is negative pressure above the canopy which lifts it. However at a certain point I would expect the oncoming airstream to counteract that force.

Are there any studies or specific knowledge about the affect?
 
I was on my way back from a burger run a couple of weeks ago and noticed that I was getting a lot of cold draft up my left sleeve. Even more than usual (I need to re-seal the canopy). Then I happened to glance over and saw about an inch gap between the canopy rail and deck on the pax side, and realized that some fool had neglected to fully latch the canopy. I had the latch halfway rotated -- it was hooked on the roll bar but not latched. My biggest fear was that it would shake loose and possibly damage the latch handle or something else as it opened, not to mention sucking who-knows-what out of the cockpit. Slowing to about 55 knots didn't allow me to close it, and I decided to fly the plane rather than screw with it in flight. I had a slightly nervous but uneventful return to the airport.

I know exactly how it happened, and won't repeat that mistake again. There are still plenty of new mistakes to make.
 
Dale,

Good job remembering the first rule. "Fly the **** airplane".

Get that canopy switch installed. I consider it one of the most important mods you can make to a -12. Many of us have taken off with the canopy half latched. I have. Not anymore.
 
Get that canopy switch installed. I consider it one of the most important mods you can make to a -12. Many of us have taken off with the canopy half latched. I have. Not anymore.

I was thinking there wasn't a way to do it with the D180, but there is. You just need to use the contact input normally used by the stall warning switch.

Step 1: Install and calibrate AOA to replace your stall warning. Simple job and cheap.
Step 2: Install canopy latch switch (N/O, closed when canopy is latched).
Step 3: Disconnect the stall warning switch from the D180. Connect the canopy latch switch to that input on the D180. Change the D180 setup to make it self-clearing, RED for open and labeled CANOPY.
Step 4: For extra credit, install a switch to detect when the throttle is more than about open, and wire it in parallel with the canopy latch switch. This one should be N/C, open when the throttle is pushed in.

Now you'll get a screen notice and audible warning if the canopy is not latched. If you install the second N/C switch, it will only sound if you advance the throttle with the canopy open. I haven't done the mod yet, but I've added that to my growing list of stuff to do either when the weather is warmer but un-flyable, or during the annual coming up in May.
 
Van's says you can't use the canopy switch

with the D-180. I can tell you that if the canopy handle moves from its half-locked to open position during full-power, 60-70 knot climb, you will get a VERY sudden and VERY quick pitch down. I was very lucky to get away with $4500.00 in damages when mine opened just a second or two after lift-off.

Wayne 120241/143WM
 
Van's says you can't use the canopy switch with the D-180.
Not without a little re-wiring, but it's certainly possible on an ELSA or EAB RV-12 (see post above). The D180 has two contact inputs for stuff just like this. You could re-purpose either one. In fact, since the spar pin warning already has its own big red warning light AND it locks out the starter, I would rather see a canopy latch status on the D180 screen than a spar pin warning if you don't want to replace the stall warning with AOA.

I'll document the process and post some pics when I install it.
 
I posted my experiences a while back (November '15)

If the canopy opens in cruise flight or close thereto with flaps up, it's windy, noisy, and very unsettliing, but no big deal. IF, however, it opens just after lift-off with takeoff (half) flaps and takeoff trim you get a VERY sudden, VERY sharp pitch-own. I was an aircraft designer (Aero engineer) at Wright-Patterson for 37 years and I think that the sharp discontinuity of the canopy being open 8-12 inches causes turbulence over the aft fuselage and significantly decreases the down-force created by the stabilator when trimmed for takeoff. My opinion, not having conducted wind tunnel tests.

However, I flew a Grumman AA-1 Yankee for 15 years before building the -12. You could fly that airplane with its sliding canopy open a maximum of 12 inches, which just caused a lot of cockpit turbulence.-- 1-3 inches was standard for summer. But I experimented to see what would happen with the canopy full open, 1) you had to hold it open-- air pressure would force it forward to 20" or so. 2) with the canopy more than 12" open you got a LOT of buffeting from the horizontal tail and a little pitch down.

Look at the profile of a Yankee and an RV-12-- VERY similar. Also the tail positions and tail volume coefficients (distance from aerodynamic center times tail area) are similar.

Sure wish Van's would conduct a flight test at safe altitude: slow to 50 knots, drop half flaps, trim for takeoff, add full power and 70 knot climb, and have passenger unlatch canopy. I'd bet on a big pitch down.

Wayne 120241/143WM
 
It is true that a GP input on the D-180 could be used for a canopy latch status indicator, but not in the way that it can on Skyview.
For Skyview, the warning is processed via software so that it only gives the warning if the canopy is unlatched and the engine RPM goes above about 3800. This is so that you only get the warning at the start of a take-off / during flight, or while doing a run-up (to confirm that the system is working.

For the D-180 all you would have is a visual status indication. You wouldn't want to use an aural warning because it would be on the entire time while taxiing with the canopy opened.
 
Sure wish Van's would conduct a flight test at safe altitude: slow to 50 knots, drop half flaps, trim for takeoff, add full power and 70 knot climb, and have passenger unlatch canopy. I'd bet on a big pitch down.

Anything that causes an aerodynamic shape change to an aircraft is likely to also cause a change in trim (in what ever axis the change might have an influence on), but I don't think comparing an RV-12 to a Yankee is valid since the Yankee canopy slid aft, and the RV-12 canopy lifts up (very different aerodynamic influence).

Numerous RV-12's have been flown and landed with the canopy unlatched (one was documented in a past Kitplanes article), with the pilots reporting that there was nothing adverse about the handling.
 
For the D-180 all you would have is a visual status indication. You wouldn't want to use an aural warning because it would be on the entire time while taxiing with the canopy opened.
That's why I plan to add the second, parallel switch on the throttle to disable the warning with less than 2/3 or so throttle. I want to set it up so that I won't get a warning while taxiing, but will if the canopy is still unlatched during runup.
 
I had the canopy open (probably not latched completely)

on about my 3rd or 4th flight, Scott. Flaps up, cruise trim, it's NOT a problem to fly the airplane. I do think that with half flaps, takeoff trim, full power, and 60 knots or so, it is. If you're less than 10 feet off the ground when that happens, it IS a big problem.

Wayne 120241/143WM

BTW, my incident was oficiallyl an Incident, not and Accident.
 
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