Bent Push Pull Rods

[EricJ]

1 hour ago, BlueDun said:

I think I see what you mean, but the hole looks the same size to me as the others. Of course, I have newbie eyes.  I will pass this along to the shop. Thank you.

What is the CD for the plane from the FAA you mention?

Anyway, all this help reminded me to make a Mooneyspace donation to support this great site. 

The FAA has a file with registration information as well as 337 forms for any major repairs or alterations (e.g., STCs) that have been submitted for your airplane.   It's essentially their collection of records for the airplane.   You can get a copy for $10 here:

https://aircraft.faa.gov/e.gov/nd/

 

[EricJ]

7 minutes ago, N201MKTurbo said:

If it was rigged properly, wouldn’t it buckle both tubes?

The adjustments can make them hit coil bind in the springs at different lengths, so whichever one hits coil bind first will bend first.

[PT20J]

On 12/15/2022 at 2:47 PM, M20Doc said:

The nose gear rods are stretched during gear extension, while the the main rods, the bent ones in the pictures above are compressed during gear extension.  Gear mis adjustment, a failed/ failing down limit switch may be causes.

Clarence, if the mechanical down stop is set correctly, won't that prevent damage if the limit switch fails?

[N201MKTurbo]

1 minute ago, PT20J said:

Clarence, if the mechanical down stop is set correctly, won't that prevent damage if the limit switch fails?

I know I'm not Clarence, but what mechanical down stop?

[N201MKTurbo]

3 minutes ago, EricJ said:

The adjustments can make then hit coil bind in the springs at different lengths, so whichever one hits coil bind first will bend first.

That's my point, they should both be very close to the same.

[PT20J]

6 minutes ago, N201MKTurbo said:

I know I'm not Clarence, but what mechanical down stop?

I assume the purpose of the mechanical stops is to back up the limit switches.

[N201MKTurbo]

1 minute ago, PT20J said:

 

Interesting, My Dukes doesn't have them.

It does look like there is one more thing that wasn't adjusted correctly.

Thanks for the info!

[EricJ]

7 minutes ago, N201MKTurbo said:

That's my point, they should both be very close to the same.

I'm not sure what the tolerance stack-up between the actuator end and the gear and the rod ends and the difference in the allowed adjustments (0.030 to 0.070) all adds up to, but I suspect it may make a difference in how much they get bent if they go into coil bind.   And that's assuming it was all rigged to spec, which is often not a good assumption.   

Plus there may be other differences in what's yielding where or not...who knows.   

[N201MKTurbo]

1 minute ago, EricJ said:

I'm not sure what the tolerance stack-up between the actuator end and the gear and the rod ends and the difference in the allowed adjustments (0.030 to 0.070) all adds up to, but I suspect it may make a difference in how much they get bent if they go into coil bind.   And that's assuming it was all rigged to spec, which is often not a good assumption.   

Plus there may be other differences in what's yielding where or not...who knows.   

I hate to say it, and I haven't done that many, but the only Mooney landing gear that I have ever worked on that wasn't messed up somewhat, was my first Mooney. It only had 1011 hours on it and nobody had ever tried to "fix" it.

[PT20J]

4 minutes ago, N201MKTurbo said:

It only had 1011 hours on it and nobody had ever tried to "fix" it.

I suspect the same goes for control rigging.

[BlueDun]

46 minutes ago, N201MKTurbo said:

If it was rigged properly, wouldn’t it buckle both tubes?

My understanding is that both push pull rods are bent. It does appear that way in the picture.

[N201MKTurbo]

2 minutes ago, BlueDun said:

My understanding is that both push pull rods are bent. It does appear that way in the picture.

Ok, but the pilots side is bent a lot more.

[BlueDun]

24 minutes ago, N201MKTurbo said:

Ok, but the pilots side is bent a lot more.

Yes, based on the angle of that pic, it appears that way.

[BlueDun]

A) The shop says wait for new rods is 20 weeks. No 3rd party options.

B) Shop suspects gear was activated while airplane stationary on the ground, although does not have evidence, and says that rods are bent for unknown reasons. 

[EricJ]

1 hour ago, BlueDun said:

Shop suspects gear was activated while airplane stationary on the ground, although does not have evidence, and says that rods are bent for unknown reasons. 

That shouldn't cause any trouble unless the safety mechanisms (e.g., airspeed switch) were faulty.  With such a long lead time on replacements you might want to make sure nothing like that could cause a repeat.

 

[BlueDun]

1 minute ago, EricJ said:

That shouldn't cause any trouble unless the safety mechanisms (e.g., airspeed switch) were faulty.  With such a long lead time on replacements you might want to make sure nothing like that could cause a repeat.

 

This is why I want to get at the root cause, if at all possible.

[PT20J]

1 hour ago, BlueDun said:

A) The shop says wait for new rods is 20 weeks. No 3rd party options.

Given that news, were it me, I would make a few phone calls myself. There are a number of salvage yards.

[Guest]

1 hour ago, BlueDun said:

A) The shop says wait for new rods is 20 weeks. No 3rd party options.

Shop suspects gear was activated while airplane stationary on the ground, although does not have evidence, and says that rods are bent for unknown reasons. 

This might help.

[BlueDun]

13 hours ago, M20Doc said:

This might help.

 

 

 

Thank you again!