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RV-12 Travel of commands

Unfortunately.....

Van's Aircraft REFUSES to release this information!
 
Van's Aircraft REFUSES to release this information!

How in the world is a builder supposed to know that the airplane was rigged properly? I mean yeah I know that these kits 12 are incredibly complete, but I think checking control surface deflections should be a very basic part of making sure that everything came together properly in the end.
 
How in the world is a builder supposed to know that the airplane was rigged properly? I mean yeah I know that these kits 12 are incredibly complete, but I think checking control surface deflections should be a very basic part of making sure that everything came together properly in the end.

You won't get argument from me. I fought this issue for months. I need the information to be assured that the airplane is rigged properly, but Van's doesn't seem to think it's important. It's almost as if they are trying to hide something.
I can't think of any other aircraft designer in the U.S. that doesn't give this spec.
 
This is a good opportunity for several owners with flying RV-12s to tell us what their deflection limits are. With several we'd have a good feel for what the plane ought to have.

One owner said that his flaperon deflections were:

Flaps up: 22.5 deg. up and 11.5 deg. down.

Flaps down (20 deg.): Referenced to the flap down position of 20 deg. flaps, the aileron deflection from there is 19 deg. up and 9 deg. down.

It would be interesting to see what other owners report.

Dave
 
Since an ELSA has to be built EXACTLY to the specs of the SLSA and Van's provides all of the parts, holes and directions to do so, wouldn't you be more concerned with following the directions? The ELSA program is designed for the feds to certify the airworthiness by making sure it was built according to Van's direction. In fact, you are the displaced factory worker and the Feds are the line inspector. One hundred and some airplanes "rigged" this way are working just fine. Its just a different way, not a right or wrong way.
 
Since an ELSA has to be built EXACTLY to the specs of the SLSA and Van's provides all of the parts, holes and directions to do so, wouldn't you be more concerned with following the directions?

But an RV-12 doesn't have to be built as an ELSA...

And either way, I'd want this information to verify I didn't screw up something like that.

And, I can tell you the same information for a Cessna 172 or most any other certified plane too. Why wouldn't you make this available? Wouldn't it be useful if there was damage to inspect or repair work done, too?
 
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Theoretically very interesting. But take the rudder for example. Its travel is limited by the physical stops. Van makes those parts, one assumes they are made precisely and correctly and changing or replacing that part based on a measurement would be a quite interesting task. Indeed, those parts do not have dimensions on the plans to check against. Elevator travel is a similar situation, with instructions provided about which stops (those on the tail or those up front in the control mechanisms) should hit first. A similar situation exists for the flaperons and flap travel is determined by the slots in the pre-slotted handle. The final checklists contain some info that is not in the plans about rigging. I was able to get those in advance - they are normally supplied only after you get the final kit and get the paperwork for registering the plane.
 
To clarify for anyone not familiar with the RV-12...
All components that would have anything to do with effecting control travel or acting as control stops in the control system of an RV-12, are completely manufactured by Van's Aircraft.

The only way control travel could be altered from what was intended, would be if a builder altered a part that does a job as a control stop.

The PAP (production acceptance procedure, a document require and approved by the FAA as part of the S-LSA certification process) provides clear concise dimensional measurements, that that when found to be of the correct values, prove that the travels are correct, and that no errors were made by Van's during the manufacture of the parts or by the builder during construction. It is true that the document doesn't supply degrees of deflection. It does supply detailed measuring reference points and required dimensions, which are actually more precise than giving degree'ed dimensions. It is challenging to accurately measure the deflection of an all moving stabilator relative to a neutral point that is not self evident. Instead of a complicated procedure detailing where the neutral position was, a simple set of measurements referenced to a reliable fixed point were used. The process used is actually less prone to measuring mistakes and in some cases is easier to accomplish (measuring for correct rudder travel for example).

So... some people may be frustrated by the fact that information wasn't supplied to do it the way they have always done it (with deflection values in degrees), but it is totally false to say that information is not provided to verify that the airplane is built in compliance to the S-LSA certificated example.

Use the PAP document check list as it was designed to be used, and everything will be verified.

BTW, should the RV-12 ever get put into production as an S-LSA aircraft, the PAP document supplied to builders is the exact same document that would be used by Van's Aircraft to inspect each aircraft for compliance as it came off of the production line.
 
So, what's the problem with giving inspectors these deflections as an additional check? We know how to measure stabilator deflection. We do it every day on other aircraft.

As an aside; I have failed at least 2 S-LSA aircraft that did not meet their specs. These aircraft had been completed and test flown in Italy before being shipped to the U.S. They had been through the factory QA, yet they did not meet spec.

My problem is not with the way you do it, but I find it somewhat disturbing that you will not allow me to make an additional check for my own satisfaction.
 
So, what's the problem with giving inspectors these deflections as an additional check? We know how to measure stabilator deflection. We do it every day on other aircraft.

As an aside; I have failed at least 2 S-LSA aircraft that did not meet their specs. These aircraft had been completed and test flown in Italy before being shipped to the U.S. They had been through the factory QA, yet they did not meet spec.

My problem is not with the way you do it, but I find it somewhat disturbing that you will not allow me to make an additional check for my own satisfaction.

Mel,
I am not going to wage a public argument with you, but your above example makes no sense to me.
If you were able to determine that two aircraft did not meet a spec. that was published, that was the fault of the person that was supposed to have verified it, not the fact that no spec, existed. In the two examples you site, was there info provided to allow for using two different methods for check for compliance? Probably it was just a situation where someone messed up.

An RV-12 is no different. Detailed measurements are supplied for the builder to verify their work and for an airworthiness inspector to double check it. It doesn't require an additional process to be able to verify it is correct, as long as the original process is valid. It is of course anyone's prerogative to question a process specified by the manufacturer, but in doing so that opens a big can of worms ( you will then need an alternate process to evaluate for proper wing spar construction, and rivet quality, and control cable swedging, and.......... it never ends)
 
My airplane is 56 years old. Without this sort of information how would anyone be able to ascertain that the aircraft is airworthy?

The information on control deflections is essential to verify that the aircraft still meets its requirements.

The best thing we can do under the circumstances is for owners to measure and log that data. It would be mighty fine if enough owners told us what they measured so that there would be a public record of the information.

And I agree with Mel here. This is pretty basic stuff for airworthiness.

Dave
 
My airplane is 56 years old. Without this sort of information how would anyone be able to ascertain that the aircraft is airworthy?

The information on control deflections is essential to verify that the aircraft still meets its requirements.

If the measurements described in the PAP were able to verify that a particular RV-12's control travels were in compliance when it was certificated, why couldn't the same measurements described in the PAP not be done on an RV-12 that is 10 years old? ( I think it is directly referenced in the Aircraft Maintenance Manual)

My suggestion for anyone concerned... wait until you have built the parts and are using the PAP checklist to do a final inspection of the airplane, to make a judgement on whether the supplied process is adequate.
 
My Air Tractor has up and down stops on all the controls and nowhere do I see deflection angles ....and it's a certified airplane.

Best,
 
Hey Scott, I have no beef with you. I know it wasn't your decision. You're just in a position where you have to try and justify it.
Van's Aircraft Inc can do whatever they want.
I just don't happen to agree with it!
 
I think Scott's statement, some people may be frustrated by the fact that information wasn't supplied to do it the way they have always done it pretty well sums up this thread. Change always has its fans and its "not-fans"...the human condition. Bottom line is: it works for the RV12. Time to move on.
 
RV 12 TRAVEL OF COMMANDS

Can someone help me? I need to know RV 12 travel in degree of stabilator , flaperons and rudder. Thanks in advance.

Benedito Angelo

I just start to build my plane, only the rudder is ready. I need the these information to fill a form from brazilian authorities to get the numbers of the plane. When the plane will be ready I will not have problem to mesure the deflections. This is my fourth project it is the first one that I did not find these information in the plans.

Benedito Angelo
From Brazil
 
Gentlemen,


Please read the posts by the builder that started this thread. He is in Brazil.

In some countries, when you start building or before, you need to ask
for an "authorization" to build. You need to submit to the civil aviation
agencies all the data of the aircraft model you wanna build. Stuff like
wing area, control surface areas and so. Control surface deflection angles
is a vital parameter that you must provide, they will request it.

Now try to explain to some aviation official that?s the way Van?s does it now. Yes, the deflection angles will be correct when the plane is finished
if you do it right, but, they want to know now what these angles should be.

Can be frustrating to this fellow builder.

I am not sure what what information he would need that has not already been made available, since there has already been an RV-12 built and flown in Brazil.
Regardless, it seems the best course of action for him would be to contact Van's Aircraft. <[email protected]>
 
Some answers

In the UK, my inspector also expected some control angle ranges to measure against, and some symmetry measurements. In the end we just measured them "for posterity".

Flaperons - up

Port up 21 degrees
Port down 13 degrees

Starboard up 24 degrees
Starboard down 12 degrees

Flaperons 1st stage down, droop 22 degrees

Port up 19 degrees
Port down 12 degrees

Starboard up 19 degrees
Starboard down 12 degrees

Flaperons 2nd sgae down, droop 32 degrees

Port up 18 degrees
Port down 11 degrees

Starboard up 18 degrees
Starboard down 11 degrees

Elevator

Up 17 degrees
Down 4 degrees

Elevator trimmer

Up 21 degrees
Down 32 degrees

Similarly, we measured airframe symmetry as follows:

Wing - rear wing tip to base of fin

Port 5000mm
Starboard 4995mm

Fin, top of spar to tail plan spar tips

Port 1705mm
Starboard 1705mm

Tailplane, tip of spar to centre of canopy handle

Port 3640mm
Starboard 3635mm

Undercarriage, main wheel to wing leading edge

Port 597mm
Starboard 603mm

Biggest difference was 6mm, that's a quarter of an inch!

Not saying this is right, wrong, or indifferent. Just what was measured.

Cheers...Keith
 
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In the UK, my inspector also expected some control angle ranges to measure against, and some symmetry measurements. In the end we just measured them "for posterity".

Flaperons - up

Port up 21 degrees
Port down 13 degrees

Starboard up 24 degrees
Starboard down 12 degrees

Flaperons 1st stage down, droop 22 degrees

Port up 19 degrees
Port down 12 degrees

Starboard up 19 degrees
Starboard down 12 degrees

Flaperons 2nd sgae down, droop 32 degrees

Port up 18 degrees
Port down 11 degrees

Starboard up 18 degrees
Starboard down 11 degrees

Elevator

Up 17 degrees
Down 4 degrees

Elevator trimmer

Up 21 degrees
Down 32 degrees

Similarly, we measured airframe symmetry as follows:

Wing - rear wing tip to base of fin

Port 5000mm
Starboard 4995mm

Fin, top of spar to tail plan spar tips

Port 1705mm
Starboard 1705mm

Tailplane, tip of spar to centre of canopy handle

Port 3640mm
Starboard 3635mm

Undercarriage, main wheel to wing leading edge

Port 597mm
Starboard 603mm

Biggest difference was 6mm, that's a quarter of an inch!

Not saying this is right, wrong, or indifferent. Just what was measured.

Cheers...Keith

Thanks Keith. You help me a lot.

Benedito Angelo
Brazil
 
I wonder.

How do you find where the stab will be for level flight?

Only then can you assign up/down degrees, no?

Best,
 
How do you find where the stab will be for level flight?

Only then can you assign up/down degrees, no?

Best,

Piper (and others) had them long before computer simulation so that is a very good question Pierre. I guess a very lucky test pilot is involved.
 
data missing to start project.

Benedito,

I perfectly understand your frustration, as I went the very same route. In Spain we can't take advantage of the ELSA certification, therefore our construction will always be "experimental". As such, the paperwork of the Civil Aviation Authorities request these data prior to authorise the building process.

I was told by my inspector that the rule was pretty much the same across the European Union, but I haven't heard of other builders in Germany, The Netherlands or the UK suffering from that.

After one month of frustration caused by delays requesting this info to Vans several times, by e-mail or phone and never getting an answer, I just made up the figures to get the green light to start building, in the hope that during the process I would be able to amend the info in the datasheet according to my empirical results. After all, being an Experimental, I was supposed to be responsible if of the design or modifications.

I'm glad to be able to compare notes now... ...and I hope my CAA inspector is not on-line in this forum!

Happy New Years' eve, and better 2012!
Godo in Barcelona, Spain
 
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