VW boxer engine used to be magnesium
They still are
When I inspect a Bonanza, one of the things I verify is there are no repairs to the ruddervators and that there are no indications of spot painting or painting without removal. The latter shows up as paint on the control cables. This means the control surface is not likely to have been balanced and is dangerous to fly.
Mines has a repair, a small tab at the trim plate, and I have purchased new skins from Beech, to renew this year. However, I was so concerned, that I removed the ruddervators,, and balanced them, to make sure the things were in balance. They are!!
It is a very critical part of the V tail. Most maintenance shops do not have a clue about just how vital balanced ruddervators are. Even a small area of paint can cause issues.
It is a very critical part of the V tail. Most maintenance shops do not have a clue about just how vital balanced ruddervators are. Even a small area of paint can cause issues.
Just a myth. Balancing of elevator or ailerons or even rudder is exactly as important – when balancing is required. It all depends on the specific design and the speed in which the aircraft operates to prevent flutter.
The main problem with a V tail is as far as I know that no specs regarding loads and strength exist in FAR-23/CS-23, same for canard by the way. Sonex aircraft experienced that the hard way with their Waiex and Xenos homebuilt aircraft. They sent out a mandatory SB for strengthening the V tail attachment points.
Just a myth. Balancing of elevator or ailerons or even rudder is exactly as important – when balancing is required. It all depends on the specific design and the speed in which the aircraft operates to prevent flutter.
I could not disagree more with any statement I have seen on the Forum. For a V tail Bonanza, balance of the ruddervator has very little available tolerance and there are reported cases of in flight flutter that nearly took the airplane down. There are ADs and SB on this specific point.
In the 1980’s there was a comparison done between the 35 and 33 versions regarding in flight breakups. It was noted that there were no tail failures in the 33, but the 35 had many. Even though the 35 has an in flight breakup rate similar to other high performance aircraft, the stark difference between the two airplanes which were identical in every respect except for the tail configuration finally led Beechcraft and the FAA to review the airworthiness of the type. In high speed dive testing, Beechcraft determined there was too much freedom of movement in the leading edge of the ruddervator (not the control surface). The ruddervator forward spar was quite far back from the leading edge and the leading edge forward of the spar was not attached by anything to the fuselage. The AD fix was to install a cuff on the fuselage that retained the leading edge back to the spar and stiffened the structure. The AD also noted the absolute critical requirement for balancing the control surfaces. Since the AD, there have been almost no in flight breakups of the type and each of those have been critically examined and pinned on bad maintenance practices such as out of balance and a flutter incident.
I could not disagree more with any statement I have seen on the Forum.
OK, so you mean balancing the elevator on an RV is less crucial than balancing some ruddervators on a Bonanza? Is flutter somehow a different phenomenon on a V-tail than on a standard tail, please explain.
It is something I have noticed very obviously in the USA. I just wonder what special features those aircraft have.
We had an S35 Bonanza in our flying club when I lived in Houston. What made me fly it a lot was:
The only real downsides I found to the Bonanza was the terrible layout of switches and engine instruments hidden behind the yoke, but this isn’t all that uncommon on other aircraft of a similar year model, and that it liked to wag its tail in turbulence.
There was also a lot made out about that the aircraft was too easy to load outside the aft cofg limit (and the CofG moves aft as you burn fuel, IIRC). I’m fairly light and all of the CofG calculations I did for any load I wanted to carry always came out within limits, so I think this is not quite as much of an issue as people made out.
It may be worth mentioning that old skool flying controls, Dakota, Beech 18, were wood and fabric for improved damping and flutter control.
There is a link with a TwinComanche exhibiting some flutter on the stabilator, will try and dig it out.
Ecco il link
It is a very critical part of the V tail. Most maintenance shops do not have a clue about just how vital balanced ruddervators are. Even a small area of paint can cause issues.
Just a myth.
Although you go on from there to expand on other areas which may also be critical, a plain reading of the exact quote above of your post is as ignorant of the balance issues in the type as any I have come across and I hope no one takes your comment seriously.
There was also a lot made out about that the aircraft was too easy to load outside the aft cofg limit (and the CofG moves aft as you burn fuel, IIRC). I’m fairly light and all of the CofG calculations I did for any load I wanted to carry always came out within limits, so I think this is not quite as much of an issue as people made out.
For the S and later models of the 35, burning off fuel follows the slant of the rear envelope limit, so until you are very low on fuel, you will remain within the CG limits if you started out within them. On my V35A, if I start out loaded with full fuel and at maximum GW and at the rear CG limit, I have to burn off 401 of the 444 pound fuel load before I will exit the rear CG limit.