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Author Topic: Something to be concerned about?  (Read 4662 times)

ghancock

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Something to be concerned about?
« on: February 18, 2016, 08:27:24 am »
My airplane just got through annual and nothing was found but we all know I got mostly a penciled annual.  As a result I've been covering the plane tip to tail to make sure everything is in good shape and fixing what I find along the way.  Last weekend though I found a couple places that have me concerned that I wanted opinions on.

The first picture shows the outside bottom of the tail section just aft of the blower vent.  It is hard to show much with a dent on white paint but hopefully you can see that both left and right sides are dented in.  I'm not sure what caused this and the left side is much worse than the right.

The second picture shows the bulkheads from the inside and I circled the areas that concern me.  Again, this type of thing may be normal and perfectly acceptable but wanted to make sure.

Opinions?

Glenn
--glenn
You can't win an argument with an ignorant person,  they'll just drag you down to their level and beat you with experience.

ghancock

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Re: Something to be concerned about?
« Reply #1 on: February 18, 2016, 08:28:24 am »
Note:  There are no loose rivots or anything I could find.
--glenn
You can't win an argument with an ignorant person,  they'll just drag you down to their level and beat you with experience.

Adam Frisch

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Re: Something to be concerned about?
« Reply #2 on: February 18, 2016, 11:24:48 am »
Looks a bit weird - wonder if she's had a tail strike at some point? Doesn't look unairworthy to me, just a little strange. But I would go over that tail area with a fine tooth comb, just to be safe. You don't want weak tails on Commanders.

On my 520, they found many of the stringers to be completely off or sawn through! Very scary, but I fixed it. I also had some dents and mis-formed bulkheads, but we corrected it with some doublers.
Slumming it in the turboprop world - so you don't have to.

Willis

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Re: Something to be concerned about?
« Reply #3 on: February 18, 2016, 01:13:59 pm »
Glenn,

Has there been any work done on the spars?  spar caps or leading edge work? 

This looks like "cradle Damage".  The dents and strain in the fuselage ribs look to be from sitting in a cradle and the total aircraft weight wasnt supported evenly with other support members or cradles.

Like Adam, these appear to be relatively easy to fix but Im thinking it would be best to remove the belly skins and straighten out the support members.  This will likely have to be done on the stands.

Consult a good sheet metal guy and see what they say.
-Bud

ghancock

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Re: Something to be concerned about?
« Reply #4 on: February 18, 2016, 09:49:32 pm »
Not that I'm aware of.  I think it was run off end of runway at some point and nosewheel had to be repaired but haven't read anything about it needing anything more major done.  Will research a bit more tomorrow.
--glenn
You can't win an argument with an ignorant person,  they'll just drag you down to their level and beat you with experience.

Jfelipe.rojasr

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Re: Something to be concerned about?
« Reply #5 on: February 23, 2018, 10:54:56 am »
Looks a bit weird - wonder if she's had a tail strike at some point? Doesn't look unairworthy to me, just a little strange. But I would go over that tail area with a fine tooth comb, just to be safe. You don't want weak tails on Commanders.

On my 520, they found many of the stringers to be completely off or sawn through! Very scary, but I fixed it. I also had some dents and mis-formed bulkheads, but we corrected it with some doublers.

Hi Adam

We are tying to replace the following stringer on a Twin Commander 690A that had corrosion. The concern is if the material has to be bended or is a natural deformation acquired by the stringer as it is installed on the wing near the fuselage.

The stringer is AND10135-1002 2014-T6511 P/N  170118-23 Left Wing

I am attaching more pictures in order to explain our requirements.

How did you repair your stringers? Just bought the extrusion angle and installed it or had to bend it?

Thanks in advanced,


Adam Frisch

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Re: Something to be concerned about?
« Reply #6 on: February 23, 2018, 03:33:55 pm »
Felipe - I don't have the answer to this. It's way out of my knowledge. It would be best if you could contact the factory Twin Commander LLC, maybe talk to Brian Harbaugh and ask him to send a drawing of the part. Then you'd know. Or you can call Bruce at Byerly Aviation and ask him to put you in contact with their main Commander and parts guy. Or call Morris.

I know you're not as comfortable speaking English as you are Spanish, but you need to get an answer to your question that only an expert can provide. Could someone else call for you? I'm hoping this thread might also clarify things.
« Last Edit: February 23, 2018, 03:35:34 pm by Adam Frisch »
Slumming it in the turboprop world - so you don't have to.