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Flew airplane after an annual, pedals are "off"


Austintatious

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OK, this explanation can get complicated if you want to know a bunch of why questions.  I am happy to answer the ones this will raise but they are irrelevant to the issue at hand.

My partner an I have 2 rockets we each own half of and recently we traded airplanes so that the one I typically fly could go through annual at his home-base where there is a readily available shop who works on both aircraft.  Well, when we traded back, this aircraft sat for a few months before I got to go fly it.  When I got in and taxied the aircraft, I noticed that the rudder pedals are not centered to go straight.  I figured I just had not been in the aircraft for a while and it was me not the plane.   Well, I have come to the conclusion that something has changed...

On takeoff and landing it is clear that the orientation of the nose wheel in relation to the pedals is off... The pedals are mostly centerd when in flight, but the right pedal must be more forward when on the ground,  this makes the moment the nosewheel touches the ground or come off the ground on landing./takeoff more exciting than it should be.

I checked for any signs of the FBO over turning the nose strut and found none.  The Shop that did the work didnt do any work on this mechanism.  My partner does not recall this when he flew it from his homebase to mine after the annual.

I don't have any idea how this has changed or what even might be wrong.... Any input would be most appreciated.

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16 minutes ago, Fly Boomer said:

Is that the practical, "real" fix, or is that process documented in the S&M?  Asking for a friend.

I didn't look it up, but I think that is what the manual says. I don't know what else you would do. 

You could get real accurate and drop a plum bob through each main axel and snap a chalk line between those points and use a framing square to snap a perpendicular bisector to align the wheel to.

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1 minute ago, N201MKTurbo said:

You could get real accurate and drop a plum bob through each main axel and snap a chalk line between those points and use a framing square to snap a perpendicular bisector to align the wheel to.

That sounds like more work, and I'm not sure the outcome would be any better.  I'll advise my friend to use the "board" method.  Thanks.

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8 minutes ago, Fly Boomer said:

That sounds like more work, and I'm not sure the outcome would be any better.  I'll advise my friend to use the "board" method.  Thanks.

The board method is pretty much what the SMM says for a J model.   There's even a drawing of clamping the board to the rudder pedals (Fig. 27-3).

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19 hours ago, EricJ said:

The board method is pretty much what the SMM says for a J model.   There's even a drawing of clamping the board to the rudder pedals (Fig. 27-3).

Buuuttt, said board is a "special tool" available only from the factory... Wait times vary 12-24 weeks and price is 1.5 AMU.

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Well, I found the problem, its not good.

I am beating myself up because in hindsight, as soon as I noticed anything I should have stopped and VERY thoroughly inspected the nose strut.  OTOH, I actually DID do that after the first landing and found nothing obvious.  In fact I inspected things 3-4 times before finding the problem and in retrospect it was probably because I was not looking in the right place, since in my mind it was a pedal adjustment issue.

Here is what I found.

 

Does this look like Damage from a tug or something else?

20221030_095047[1].jpg

20221030_093540[1].jpg

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In the manual it looks like an angle iron, with maybe some wood pads for the clamps.    It's probably a kit available from Mooney or LASAR, but with interest rates high now getting another mortgage to pay for it might be more difficult.  ;)

image.png.d20d89d5aa0b048f5da8d7c857a26ead.png

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2 minutes ago, Austintatious said:

Well, I found the problem, its not good.

I am beating myself up because in hindsight, as soon as I noticed anything I should have stopped and VERY thoroughly inspected the nose strut.  OTOH, I actually DID do that after the first landing and found nothing obvious.  In fact I inspected things 3-4 times before finding the problem and in retrospect it was probably because I was not looking in the right place, since in my mind it was a pedal adjustment issue.

Here is what I found.

 

Does this look like Damage from a tug or something else?

20221030_095047[1].jpg

20221030_093540[1].jpg

Ouch, sorry to see, but it is fixable.

Since the metal at the crack isn't clean it's likely been growing for a long time.   There's no telling what caused it originally or when.   It may have been a porpoise or other hard landing sometime in the airplane's history.

Tug damage from exceeding steering limits shows up elsewhere, on the truss tubes.

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Just now, EricJ said:

Ouch, sorry to see, but it is fixable.

Since the metal at the crack isn't clean it's likely been growing for a long time.   There's no telling what caused it originally or when.   It may have been a porpoise or other hard landing sometime in the airplane's history.

Tug damage from exceeding steering limits shows up elsewhere, on the truss tubes.

Yea, I hear you on the truss tubes... as for the metal not being clean, it is possible this happened 2 months ago... I had been busy and the aircraft had not been flow (shame on me I know)

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9 minutes ago, bluehighwayflyer said:

Ouch!   I’m glad you found this before it could fail completely.  Although I’m a big fan of both the Rocket and the Missile it stands to reason that they put more stress on their nose gears.  All of the other “big engine” Mooneys had their nose gears relocated forward.  The fleet size is small enough that it might never be noticed officially but if I owned one I would be paying extra special attention.

The rudder pedal adjustment tool is just a thin wall steel tube split down the middle.  I’ll try to remember to take a picture of it and post it here the next time I go to my hangar.  

I doubt that this has much if anything to do with the extra weight in the nose... Rocket added another battery in the tail and typically a lot of charlie weights... The CG envelope remains the same, but there is indeed a slight forward movement of the empty CG, though it is still in the envelope.  One would hope the engineers wuld have designed the nose strut to be able to hold up to a forwardmost CG.

I am not still convinced that this did not happen during tow... The strut brace on that side making contact could cause the exact failure that I see.  One would think that the tube would crush first, but it may have been a case of a pre existing crack opening up when it was oversteered... A mechanic will have to look and make a determination...

 

Does anyone know anything about doing an "owner repaired" part in a circumstance like this?

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14 minutes ago, Austintatious said:

Does anyone know anything about doing an "owner repaired" part in a circumstance like this?

OPP can be done on essentially anything, but it must be done to acceptable repair standards for an airworthy repair.    The hurdle on these may be the potential heat treatment requirement if such is required in the SMM, IPC, or other applicable documents (SBs, Mooney drawings, etc.), and I don't know off the top of my head whether those are an issue or what they might be, or how difficult it might be to find a repair shop that could do it.     An alternative form of getting a repair method approved would be through a DER or DAR, which would cost money for consulting time.

While an OPP path may be worth some research (and I'd definitely check into that if it was me), finding a replacement, even a used one, may ultimately be a much less painful solution.

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My $0.02:  This is the time to go junkyarding. Start making phone calls, I'm afraid.  I had to find a replacement elevator after my hangar rash incident...ended up finding one at a yard in Texas that specializes in Grummans!  No idea why they had a Mooney elevator, but they did!

Trying to fix this properly sounds like a lot more work to me.

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In addition to the junkyards I’d definitely be on the phone to both Lasar locations and Dan to see if they are still doing any instead of all of us guessing.  And Maxwell and Topgun as they probably see a lot and know what to do for parts.

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4 hours ago, bluehighwayflyer said:

CG and the weight in the tail have nothing to do with it.  I am talking about the amount of weight forward of the nose gear and it’s relative moment and the increased stresses that are imposed on the nose gear during landing as a result.   I am not suggesting that anything doesn’t meet certification standards or trying to cast aspersions. It’s a good idea in all airplanes so equipped to protect the nose gear.  I’m just suggesting that it might be especially so in the M20 fleet in the Rocket and the Missile.  

I would say it has a lot to do with inertia, even if the nose had no additional weight the heavier engine has greater inertia and takes more force to displace it when taxing over bumps etc. My SWAG is high cycle fatigue, but it could have been a one event thing, but I would think that would have been memorable?

It should honestly be a pretty easy repair, if you could find the heat treat level there are places that heat treat of course.

Without a jig I wouldn’t try building one from scratch myself, even with a jig your up against that heat treat thing still.

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31 minutes ago, Ragsf15e said:

In addition to the junkyards I’d definitely be on the phone to both Lasar locations and Dan to see if they are still doing any instead of all of us guessing.  And Maxwell and Topgun as they probably see a lot and know what to do for parts.

Anyone who finds out, please post if anyone is

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The crack is suspiciously at the point where the turn stops attach. And, it looks like there may be a ding in the piece that hits the stop bolt. I’ve seen pictures where the stop weld breaks when oversteered, but maybe this is a really good weld and the tube gave out instead. Hard to tell.

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13 hours ago, A64Pilot said:

So who repairs these now, I’ve heard LASAR is no longer and that the part has to be heat treated

 

11 hours ago, Alan Fox said:

AWI won’t touch them..

Lasar advertises them.  Not sure what you mean by "Lasar is no longer".  They may not have any in stock and need a core first.

REPAIRED NOSE TRUSS — LASAR

las.png.908e748faedb9b166a90e27ce48a1700.png

Edited by 1980Mooney
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Is the plane usually towed with a tow bar (and help by pulling on the propeller) or with a little tractor? The '79 J in my hangar just broke its nose wheel bolt and they suspect it's due to being towed with a little tractor over the bumps where the hangar doors slide back and forth.

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