Flap control rod found during annual

[DCarlton]

On 8/18/2021 at 11:49 AM, Shadrach said:

First time annual, probably not. A well known aircraft with 10 previous inspections and a proactive owner that does not defer squawks? Two days is plenty for the inspection. I don’t know how long you’ve had your plane or what kind of environment it is operating. A Hangared airplane that flys 100 hours a year should not be that filthy if it’s reasonably oil tight and. If a panel hasn’t been off in 20 years than I would expect some pretty serious grime. There’s not a panel on my aircraft hat hasn’t been off in the last three years. More often than not, it looks pretty much like I left it.

It also helps to have reasonable expectations. Making something airworthy and making it pristine cannot be done in the same time frame.   If I’m hiring an A&P to make something airworthy that’s my expectation and no more. If I want more, I’ll ask for it and expect to pay accordingly. Replacing an alternator doesn’t mean that everything ahead of the firewall gets detailed. It doesn’t mean that anything gets detailed…I expect to have an operable alternator. I consider it a bonus if there are no fingerprints anywhere to be found after the job

I've owned it for 17 years.  Maintenance hasn't been deferred.  But... I live in one of those SOCAL areas where hangars are next to impossible to come by.  So some of the cleaning and detailing gets pushed to the annual.  I recently retired so I simply had more time to apply to the annual.  I maximized use of the hangar time offered by the mechanic.  Next year, I'm hoping to do more throughout the year to make the annual go a little quicker. 

[Guest]

On 8/18/2021 at 8:09 AM, Shadrach said:

My IPC doesn’t show that.  I’m pretty sure I haven’t seen nearly as many of these as you have. My belly pan will be coming off next week so I’ll get a look then.

This may be helpful.  Trim tube wear inspection limits and taping requirements 

https://www.mooney.com/wp-content/uploads/2020/12/SBM20-185.pdf

[bob865]

3 hours ago, M20Doc said:

This may be helpful.  Trim tube wear inspection limits and taping requirements 

https://www.mooney.com/wp-content/uploads/2020/12/SBM20-185.pdf

That's interesting.  My E is not in the affected range of the service bulletin.  But it does look like a good idea to implement it anyway.

[Shadrach]

34 minutes ago, bob865 said:

That's interesting.  My E is not in the affected range of the service bulletin.  But it does look like a good idea to implement it anyway.

My serial# isn’t listed but I suspect it has the nylon grommets. I’ve never seen this SB. I’d also say I’ve not seen any evidence of friction wear on the torque tubes.

[PT20J]

According to the IPC, the M20Js used teflon tape through S/N 24-0810 and then switched to heat shrink tubing. The heat shrink on mine was loose but I was able to heat it enough to tighten it up. 

Skip

[Ragsf15e]

2 hours ago, Shadrach said:

My serial# isn’t listed but I suspect it has the nylon grommets. I’ve never seen this SB. I’d also say I’ve not seen any evidence of friction wear on the torque tubes.

I didn’t feel anything either, but during an annual at Top Gun, they found wear past the limit.  Apparently the bulkheads it passes through will cut it effectively as it spins.  You don’t want that to happen. Trust me.  Had to order a new trim tube from the factory.  Lots of $$ and time fixed it. As a bonus, now it’s the cleanest looking tube going back towards the tail!

Edited August 20, 2021 by Ragsf15e

[Shadrach]

2 hours ago, Ragsf15e said:

I didn’t feel anything either, but during an annual at Top Gun, they found wear past the limit.  Apparently the bulkheads it passes through will cut it effectively as it spins.  You don’t want that to happen. Trust me.  Had to order a new trim tube from the factory.  Lots of $$ and time fixed it. As a bonus, now it’s the cleanest looking tube going back towards the tail!

I didn’t mean evidence in the trim control, I meant no evidence on the surface of the tube during past annuals. Will be looking closely next week.

Edited August 20, 2021 by Shadrach

[Guest]

A piece of tape or heat shrink is cheap insurance against tube replacement.

Clarence

[Guest]

4 hours ago, Shadrach said:

My serial# isn’t listed but I suspect it has the nylon grommets. I’ve never seen this SB. I’d also say I’ve not seen any evidence of friction wear on the torque tubes.

The search engine on the Mooney sight was changed awhile ago.  Search your model and you get every bulletin since the dawn of time.  It now takes more time to sort through them.

https://www.mooney.com/contact-2/#technical-publications

Clarence

[Shadrach]

5 minutes ago, M20Doc said:

A piece of tape or heat shrink is cheap insurance against tube replacement.

Clarence

Thanks Clarence. The SB does not describe the type of tape used. I’d rather not remove tubes for shrink wrap. Is there a preferred type of tape?

[Guest]

5 minutes ago, Shadrach said:

Thanks Clarence. The SB does not describe the type of tape used. I’d rather not remove tubes for shrink wrap. Is there a preferred type of tape?

Step 7 in the instructions list the tape.

Clarence

[Shadrach]

18 minutes ago, M20Doc said:

Step 7 in the instructions list the tape.

Clarence

Yes but #Y-9265 does not seem to be available. It seems I could have it made at a minimum of 72 rolls.  Hoping to find something readily available.

Edited August 20, 2021 by Shadrach

[PT20J]

1 hour ago, Shadrach said:

Yes but #Y-9265 does not seem to be available. It seems I could have it made at a minimum of 72 rolls.  Hoping to find something readily available.

I would use some UHMW tape.  You can get it on Amazon. It’s made for this sort of application. I used it on the belly to protect the wing skins where the gear doors rub and it’s held up really well.

Skip

[carusoam]

UHMW (PE) is often used for wear resistance… it is kind of a slippery material, and extra tough at the same time….

Probably similar tape used on sliding surfaces near the tail hinge….

 

Often, people are looking for a version of Teflon, because it is known for its slipperiness… unfortunately, Teflons are pretty soft and can capture dirt embedded in its surface… the dirt makes a really good sandpaper….

 

PP thoughts only, not a mechanic…

Best regards,

-a-

[Shadrach]

On 8/18/2021 at 7:55 AM, M20Doc said:

Most have a black heat shrink type of material slid over the aluminum tube as further wear protection.

Circling back on this. After removing all the belly panels for annual, I got a good look at the torque tube. My 67 F has both a sheath and a phenolic block.  There is no record in my logs of these parts having been added.  @bob865’s plane is 8 years newer so the decision to omit these parts was likely made by factory bean counters sometime between 1967 in 1975.

Edited September 4, 2021 by Shadrach

[Ragsf15e]

3 hours ago, Shadrach said:

Circling back on this. After removing all the belly panels for annual, I got a good look at the torque tube. My 67 F has both a sheath and a phenolic block.  There is no record in my logs of these parts having been added.  @bob865’s plane is 8 years newer so the decision to omit these parts was likely made by factory bean counters sometime between 1967 in 1975.

My ‘68 didn’t have the tape and the block was much less robust  than that one.  I bet yours were added and invisible in your logs.  Especially the tape I think it’s more recent than’67.

Edited September 4, 2021 by Ragsf15e

[Vance Harral]

On 8/19/2021 at 7:05 AM, bob865 said:

I learned from this that the flaps are connected, so there is no possibility of asymmetric deployment

While asymmetric flap deployment is "unlikely", it is not "impossible".  That big torque tube to which the actuator attaches isn't connected directly to the flaps.  Rather, the torque tube is welded to a control horn, to which yet another rod attaches, which in turn connects to a horn connected to the flaps.  The rod is comprised of two rod ends held together with jam nuts.  If the jam nuts, or the rod ends, or their connections to the control horns fail, you'll get asymmetric deployment.  Again, this is very unlikely, but I wouldn't tell anyone there is "no possibility of asymmetric deployment".

[Shadrach]

3 hours ago, Ragsf15e said:

My ‘68 didn’t have the tape and the block was much less robust  than that one.  I bet yours were added and invisible in your logs.  Especially the tape I think it’s more recent than’67.

Perhaps. It’s ostensibly a one owner bird and I have all the logs. Most of the mx was performed by an on field MSC. If they farted while turning a wrench it would make it onto the invoice and likely the logs as well. Seems relatively involved to just forget about and my dad was not a wrench turner.