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Modifications that you have Made to your RV-12 after Certification? E-LSA Only!

Throttle springs

I did not like the strong throttle springs pulling the throttle control out of my hand or causing the throttle to slowly advance. So I replaced the original springs with Century Spring part number 6049. I could not find any stock spring with the properties that I wanted, but the 6049 came closest. The 6049 is 2" long and needs to be shortened 1/4" to work on the Rotax carburetors. The original springs are made with approximately 0.045" plated steel and both ends are clocked the same. The Century 6049 springs measured about 0.040" and are made of music wire and the ends are clocked 90? apart. After cutting and bending the extended hook on one end, I baked the springs at 400? in the kitchen oven for an hour to relieve stresses. I do not know if that was necessary or not, but it did not hurt the springs. At idle, the original springs pull with 8 pounds of force compared to Century Spring 6049 at 4 pounds. Although the throttle will still creep forward if the friction knob is not tightened enough, the weaker 6049 springs have improved throttle operation. I have flown one test flight with the new springs, and made several touch and goes without a problem.
Century Spring has a minimum order, so I have extra springs.

Rotax does not approve the 912ULS for IFR. Now that I have modified the engine with new springs, it is no longer a Rotax engine but a Joe's Special approved for IFR. At least that is my story and I am sticking to it. :D
Joe
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Canopy Latch Retaining Spring

Found a dandy extension spring to keep the canopy handle from migrating aft and preventing canopy opening without releasing the external latch.

It's a 2 1/2" X.016 spring with a *very* light tension. Comes in a blister pack with a smaller spring, about $3 at Home Depot.

I rigged it up like the spring on my old slider canopy.

Jim
RV12 N233TX
flying
 
Thanks to everyone for posting on this thread, as I've found it very helpful. I'm trying to decide what the next airplane for us should be, and the RV-12 (and S-19) are at the top of the LSA column of choices...but building out a kit, especially an LSA kit, is a whole new concept for me.

One puzzle I've been noodling is just what is a permitted E-LSA 'modification'? What's allowed, what's not? (I had assumed it wasn't as wide open as "normal" Experimental aircraft). I hadn't broken this down into pre-AC and post-AC issuance (which by itself is helpful to me in how to think about this) and I can see most (all?) of you posting here seem to believe you can modify or supplement many of the minor aircraft systems. I don't see anyone talking about changing the engine or airframe, so obviously there's a line drawn somewhere that defines post-AC issuance changes that are vs. are not acceptable. Can someone roughly define that line for me? Is it as "simple" as continuing to comply with the ASTM standards?

Presumably, there are no mods permitted to the kit as it comes prior to AC issuance. Is that a fair statement?

Thanks for putting up with some pretty basic questions. Hopefully, I'll have a much better feel for this whole subject after attending the Sebring Expo next month.

Jack
 
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The aircraft (E-LSA) must be presented for certification exactly as the plans specify. Any modifications must be authorized by the kit manufacturer in writing.
Once the aircraft has been certificated, it is Experimental and you are free to make ANY modifications you like so long as the mod does not take the aircraft beyond light-sport parameters. i.e. maximum speed, clean stall speed, max gross weight, etc.
Keep in mind that if the aircraft is taken beyond light-sport rules for any reason, it can never be returned to LSA.
 
Can someone roughly define that line for me? Is it as "simple" as continuing to comply with the ASTM standards?

Presumably, there are no mods permitted to the kit as it comes prior to AC issuance. Is that a fair statement?

Jack

Jack, I think the `line' you refer to is that if you have built the plane as an E-LSA then your post AC mods are not allowed to take the plane out of the LSA performance parameters. Pre AC, if you're building it as a E-LSA,you can't change anything without approval from Vans. However, if you chose to build it EAA, you can change what you like, when you like - same as any other EAA aircraft. That's my understanding of the rules, but no doubt someone will correct me if I've got it wrong.
 
Just to add to Robert's post, If you build as amateur-built, you may make any mods you like from the beginning. In this case, your mods MAY take the aircraft beyond LSA parameters, BUT, if so, the aircraft will never be eligible to be flown by a sport-pilot.
 
Thanks, fellas. I think I've got it. And I'm surprised the E-LSA, post-AC option is so flexible. Very appealing...

Jack
 
Safety Magnetic Plug

I made an anchor to safety the Magnetic Plug on the Rotax. Under the oil filter, there is a threaded, blind hole that was used to hold the engine in the shipping crate. I drilled the head on one of the crate mounting bolts, screwed it into the blind hole and use it to safety the magnetic plug. (that plug that is forward of the oil filter is wired to the same anchor)

I also safety wire the nut-bracket-nut connection on the carburetor end of the throttle cables.

This time of year, Oil Temp and CHT are at the bottom of the green. I've covered 1/3 of the radiator with Aluminum to try to get more heat in the cabin, I'll report on that later.
 
This time of year, Oil Temp and CHT are at the bottom of the green. I've covered 1/3 of the radiator with Aluminum to try to get more heat in the cabin, I'll report on that later.

Solved my winter time oil temperature problem via the installation of an oil thermostat and low CHT temperature issue via the installation of a coolant radiator damper/door.

The photos also show the installation of the Reiff pre-heater.

All three work VERY well. The photos are located on Picassa.

http://picasaweb.google.com/marty.s...orOilThermostatReiffPreheater?feat=directlink
 
Great work, looks like that damper door took a bit of time to design and build. If my easy fix doesn't do enough, I may borrow your design.

We have a guy on the field who installed a coolant thermostat in a radiator hose, it works great in the winter, but runs too hot in the summer and he has to remove it.

thanks, GDS
 
Flapperon Trim Spring

No, I haven't installed one. Just hoping someone has modified the Vans aileron trim rig offered on other models for the 12. And will post a photo or sketch. I'm not lazy; just lack the engineering gene. And if I have to pull all 200 of those screws holding the over-controls panel off again, I want to have a sketch and a materials list!

Jim
RV12 120264
flying hands-off with one aboard
 
Canopy Lock

After seeing Jetguy's posting I also decided to install a lock. Instead of placing the lock below the longeron I placed the lock further aft in the turtle deck skin. The arm hooks into the frame.

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I have added the following to N167SW: Ray Allen G303 stick grip (PTT trigger plus elevator trim on the stick), I'm swapping out my Garmin 495 for a 695 (in progress), Closed the tank sight window, added the Moeler mechanical guage, and modified the ribbed tail cone close out (behind the tank) so that an inspection can be done without having to remove the tank. At annual, in June, I plan to redo the Rotax throttle cables, so that they will be spring loaded to idle, not full power, the way they are now. The latter just strickes me as a ground accident waiting to happen.

Steve, do you have any pictures of the mod that you did on the ribbed tail cone closeout to gain access. Any info that you have would be helpful. I want to do something before putting in the fuel tank so if I ever need to gain access back there (autopilot servo) I won't have to take out the tank. Thanks.
Doyle
 
REMOTE OIL SENDER

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Run the hose down-hill for self-bleeding. Seems to work well. Just bought pieces and filled the 1 engine fitting and drilled a #70 hole in the filler. Doesn't jump all over now on the display.

230.7 hours as of today.

John Bender
 
A couple of minor mods...

Headset straps...I posted about this before somewhere, but here it is again in the mod thread. This minor mod eliminates the problem of the headsets always being in the way during entry and exiting the aircraft and the passenger usually figures out how to don their headset and stow it at the end of the flight without my help. Available from Abby at Flightline Interiors for a pittance.
[url=http://tonytessitore.smugmug.com/RV-12Project/Mods/16382368_9iheb#1289966777_jJdSVMx-A-LB][/URL]

After considering several locations, I mounted a small halon extinguisher using two nutplates in the fuel valve tunnel cover where it is in plain sight of pilot and passenger but not in the way of either:
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Tony
 
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Nice tip on the headset hangars Tony, but on my recent trip I found a fellow that put the RV10 vent handles on the vents, which not only gives a better feel on the opening and closing of them, but provides a very neat headset hangar as well.
 
Get the position/strobe light switch fixed!

One mod I've not seen mentioned here is one that I recommend to all builders is; Install a separate switch for the strobes. Position and strobe lights should never be on the same switch for 2 reasons.

1/ You should not run the strobes on the ramp at night. It will really "tick-off" other pilots.

2/ There may be times in cloudy weather when you need to turn the strobes off to avoid the blinding reflections but the position lights should remain on.
 
Nav/Strobe Lights

Hi Mel,

Great suggestion, but it will require running an additional wire through each wing since the red(nav) and yellow(strobe) power wires are spliced together at the wing tip to a single 18 ga supply wire.

Additionally, another contact at the each wing root would have to be added if the builder decided to keep that system.

By the way, the Aeroled manufacturer schematic recommends 20 ga shielded 3 wire to the nav/strobe unit and separate CB's for the nav and strobe.

Mitch Garner

RV12 fus and wings under construction
 
Hi Mel,

Great suggestion, but it will require running an additional wire through each wing since the red(nav) and yellow(strobe) power wires are spliced together at the wing tip to a single 18 ga supply wire.

Additionally, another contact at the each wing root would have to be added if the builder decided to keep that system.

By the way, the Aeroled manufacturer schematic recommends 20 ga shielded 3 wire to the nav/strobe unit and separate CB's for the nav and strobe.

Mitch Garner

RV12 fus and wings under construction

Hi Mitch,

I have put the extra wires in to separate the nav and strobe functions. I have also placed wiring to the right wing as I hope to install the landing lights on both wings.(I will need to wait until some one works out how this can be done, my best tool is a hammer) Are you saying that the 18 ga should be changed to 20 ga sheilded 3 wire cable? I am just wondering if it is alright in the original design to have 18 ga is this somthing I should change?

Thanks
Julian RV120316
 
The only reason to change to a smaller wire is weight. And changing from 18 to 20 ga. won't make that much difference.
Stick with 18 if that what you already have.
 
Hi Mitch,

I have put the extra wires in to separate the nav and strobe functions. I have also placed wiring to the right wing as I hope to install the landing lights on both wings.(I will need to wait until some one works out how this can be done, my best tool is a hammer) Are you saying that the 18 ga should be changed to 20 ga sheilded 3 wire cable? I am just wondering if it is alright in the original design to have 18 ga is this somthing I should change?

Thanks
Julian RV120316
At the risk of conjecture, When I look at the new panel layout for the RV-12, there appears to be a two position switch, one for nav, the other is labelled nav+strobe. This is based on the picture recently released by Vans. There is also a two position switch for the landing light (pulse/steady) as well.
 
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Start a new thread?

I would like to contribute to the wing wiring discussion, but this is gettting way off topic. Mr. Moderator, how about starting a new thread and moving these last few posts to it? Maybe call it "Wing light wiring options" or something like that.
 
Fuel Tank Drain Valve

In the UK we can make mods to our RV-12s during build as they'll operate under our version of the US Experimental category. We get the mods approved by our Light Aircraft Association who look after homebuilds.

I wanted to have some form of fuel tank drain for pre-flight checks and also as a handy drain point for the tank.

Initially I looked at fitting a gascolator in the line below the tank but there really wasn't space with the stab/rudder cables running through that area. Instead, I came up with a much simpler method which should work fine. One advantage of this set up is that it uses the standard pipe out of the tank to the electric fuel pump just cut at the 90 deg bend to introduce the tee piece.

I'm awaiting final approval but I can't see any reason why my set up shouldn't work as forecast and won't reduce fuel flow at all. Feel free to comment if you can see something I can't!

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Fuel drain

Neat installation. A leaky valve would be a problem, but otherwise it looks like a very good idea to me.
 
Fuel sump

Looks like a great idea! Anybody know the reason Van's didn't include a drain in the original design? I'm sure they must have considered it. Is there a downside other than a very slight weight increase or a possible leaky valve?
 
Turnbuckles?

Jerry,

Any reason why you are using safety wire rather than those little clips in the turnbuckles?

Cheers...Keith
 
To answer the questions... Drain valve could leak but the same has to be said for all aircraft with drains in the fuel tanks (which is pretty much all aircraft except an RV-12!). Valve is standard one and the same as used in the RV-12 gascolator.

As for the turnbuckle wirelocking, Keith - I hate those poxy clips with a vengeance! They rarely comeout cleanly without getting bent. I've been wire-locking turnbuckles for 30 years and it's quicker for me to it than use the clips...
 
Gascolator Shroud/Scat

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Hopefully the photos of the mod appear above. If not, I tried.

INSURANCE FOR WINTER GAS IN HOT WEATHER

The forward attachment is just a piece of PVC glassed in place. It will get painted eventually. The scat routing is pretty much self-explanatory. The gascolator shroud was made by making an over-size dummy of the gascolator out of foam for a mold. I used a section of piano hinge and bent aluminum to allow passage over the fuel outlet. Two AN3 nutplates were installed to attach the unit. I sprayed the f'glas with high-temp reflective paint. The shroud is over-built and ugly but it works and nobody has to look at it except me. PM me if you have questions; glad to answer 'em.

Jim in South Texas

p.s. Oh yeah, I had to relocate the attachment for that overflow tube. You can see it in the last picture. And a stand-off and longer bolt were required for the cooling hose, which is visible in next-to-last photo. j
 
My Piano Hinge Pin Tool

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I expect many of you have developed some kind of tool for wrassling those cowl pins into and out of place. This is what I fabbed up from a cheap pair of needlenose. Drilled hole in jaw edges to hold pin. Sharpened the tip to a point for possible use as a canopy-cracker. I keep this tool in the top pocket LH side.

If I did it again, I would find a longer pair so it would be easier to reach the lower cowl pins.

Jim
#264
 
Parking Brake

One mod I was waiting to install - was a parking brake! I see little mention of this among the RV12 owners, but Vans sells an easily installed valve for this purpose, called a PV-1 by Matco as I recall. I have acquired one and will install it on mine. I could not feel comfortable leaving my plane parked with no brakes set, heck even my Ercoupe has a parking brake.
 
Because I am a bit lazy I guess. Carrying them along, climbing in and out with them, seems like more work than just pulling the valve.
 
Parking Brake

One mod I was waiting to install - was a parking brake! I see little mention of this among the RV12 owners, but Vans sells an easily installed valve for this purpose, called a PV-1 by Matco as I recall. I have acquired one and will install it on mine. I could not feel comfortable leaving my plane parked with no brakes set, heck even my Ercoupe has a parking brake.

The South African guys installed one. There are some photos of their installation somewhere in their build post, as I recall.
 
Hmmmm.....I like it!! Maybe just remove the cable locking arrangement in the end of the arm, replace it with a longer "handle", and slot the tunnel closeout panel so the handle sticks through! Crude...but simple!;)
 
structural item

The tunnel cover is a structural item. A small round hole would not weaken it as much as a slotted hole. Maybe the parking brake valve could be mounted in such a way that the valve handle could be operated using a push rod through a small hole.
Joe Gores
 
I just installed Jetguy's (John ) fairings. Very quick install with #6 screws. If they strip out I will add nutplates, but for now screws with a touch of red lock tite will do just fine. A very nice product, but it must be painted. I shot it with a rattle can.

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A very nice fitting product.
 
Sure look great, will save me the trouble of making some for my plane. I wonder if gear leg fairings are on the horizon?
 
Source

Strangely enough I found a huge selection of those "round-key" type locks at a recreational vehicle store, where they are used to secure panels and such. Clerk asked me what kind of RV I had; I told him a 12.

Try and get one with a short barrel so the latch will swing up nicely into the 3/4" square tubing in the canopy bottom. You may have to do some filing on the latch for a good fit. A 3/4" punch used by electronics guys is perfect for making a clean hole in the side skin. Dremel and small files to finish.

I had to modify the key on mine by filing off the "tooth" so that I could remove the key at the stopped position. There's a gizmo on the back of the lock that prevents it from rotating back until the key is reinserted. Most of the 5 hours was devoted to fine-tuning this install. Downside is estimated loss of .0003256 knots airspeed due to parasite drag of outside portion of lock.

Jim
 
Seat Back Fuel Tank

Jetguy posted a picture of my fuel tank at OSH:
http://www.vansairforce.com/community/showpost.php?p=562072&postcount=39

I put pictures on Picasa:
https://picasaweb.google.com/117081108891056780334/SEATBACKFUELTANK?authuser=0&authkey=Gv1sRgCLnX4YDy0PuVaQ&feat=directlink

Advantages:
No sight glass. Fuel level can be seen through the filler neck.
Tank does not have to be removed for annual inspection.
Sump allows almost all fuel to be usable.
Fuel lines are disconnected from inside of cockpit, not underneath plane. Fuel will not run down your arm.
Baggage area is much bigger.
Burning of fuel will have little effect on CG.
Less chance of spilling fuel on rear window because fuel cap is below window, not beside it.

Disadvantages:
Baffles and shape of tank cause weight increase.
One can not lie in prone position with head in tail cone.
Landing gear center channel can not be used for storage.
Not yet tested for crash resistance. And hope I don't :D
One must stand on step or wing to fill tank.
No kit or plans are available.
Requires relocating ELT. (I moved it into tail cone.)

Van liked the tank. I think there is a 50-50 chance that he will use my idea. First it has to make sense business wise. It will cost money to design and crash-test and change the plans and setup the tooling. I think this new tank will make the RV-12 more marketable.
One mistake I made was not punching large enough holes in the baffles. I spilled fuel because the tank could not accept fuel as fast as the airport pump filled it. I did not have that problem when filling with auto fuel from 5 gallon cans. My tank has about the same capacity as the original, although it would be easy to enlarge it towards the aft if desired.
Joe Gores
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Nice design Joe. Makes the baggage area more usable too. Any chance of a few more photos of the setup and a sketch plan?
 
Gosh Joe, had I known you had that mod, I would have found you regardless! That is really nice, I would go for that mod in a minute. More photos would be appreciated!
 
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