Strut ad

[dedrekon]

I don't doubt this has been discussed, dissected and debated ad nauseum BUT, just to clarify my thinking:

Other than new replacement struts, you can either have them X-Rayed, Borescoped or do an Ultra Sound, all of which are good for four years before the next inspection OR if they we're initially eddy current tested when the AD first came out, that was good for two years after which one of the other methods must be used going forward.

Do I have this right?

Vincent

[mulwyk]

Re: Strut ad

That's my understanding, Vincent. Or put another way, you can:

Buy new ones = $2000

Inspect and seal old ones = $1000

Inspect every 4 years = $200

[3Dreaming]

Re: Strut ad

I may have missed it, but I don't remember seeing borescoping as an inspection method listed in the AD. Wag Aero's sealing of the old struts requires borescoping as part of thier procedure. Tom

[fearofpavement]

Re: Strut ad

I agree with Tom, boroscoping is not one of the listed inspection methods accepted by the AD. (other than in relation to getting the struts reworked) For the best information, read the AD itself, it is all laid out in there. (make sure you're using the latest version.)

[Guest]

Re: Strut ad

Borescope/fiber scope is part of the service bulletin for the fitting inspection, not the strut ad.

[blakecarl]

Re: Strut ad

I need to get our struts inspected and am looking for ideas on finding a qualified company / person. Is FAA certification required of the company / person doing the inspection? Is there a listing of companies / persons qualified and or certified to do inspections? If not, what would a person look for in the yellow pages to locate someone?

Thanks for any and all help.
Blake

[Hank Jarrett]

Re: Strut ad

Pack them up and send them to WAG Aero to be converted to sealed struts. Then you will be done with it.
Hank

[Ray36048]

Re: Strut ad

How much money do you save by having Wag Aero inspect and seal them vs buying new? How much do you spend for shipping?

[VictorBravo]

Re: Strut ad

Please remember that the lower longeron cluster and strut attach fitting is subject to possible corrosion damage. No matter how much money you spend on struts, there is still a critical area of the airplane that would not be addressed by sealing the struts, or buying new ones, etc.

Forum member L-2 Gary has made a point of X-ray inspecting the lower cluster every ten years. When the strut AD fiasco came out, he had a great idea that we could have the mobile X-ray done in a way that covered the lower strut as well as the cluster.This worked out very well, because we were able to look and see inside the lower strut, lower longeron, weld cluster, and fittings all at the same time.

I agree with Hank about having the struts sealed once and for all... nice to not have to worry about it... however that is the same as only checking the tires on the left side of your car before a road trip. IMHO you would still need to X-Ray the fuselage to have the highest level of security, even after you spent the money (wise investment regardless) on sealing the strut.

For my ability to sleep at night, having the lower cluster/strut/fitting X-Rayed every four years for a few hundred bucks is really cheap insurance on a 65 year old plain steel airplane. If I had to choose, seeing that my entire structure is clean right here and now in front of my eyes is far preferable to having HALF of the structure sealed (so it will probably not ever corrode) and then forgetting about the other half.

[3Dreaming]

Re: Strut ad

How much money do you save by having Wag Aero inspect and seal them vs buying new? How much do you spend for shipping?

It's about 1/2 of new, and they can tell you how to inspect before yopu send them.

[Dano"T"]

Re: Strut ad

send them to Great Lakes Testing in Green Bay, WI.....$50 per strut....it's not really a big deal to take them off.....just brace the wings......mark the position before you remove them. You can save $$$ by just inspecting them. $200 every 4 years would be 40 years worth vs. new sealed one's if the cost remained the same...figure for inflation and you still probably have the same ratio because the cost of the new ones will go up too.

[blakecarl]

Re: Strut ad

There’s a new development regarding our existing struts—I didn’t mention this in my previous post but our plane is being annualed. Both front struts have dents that were there when we bought the plane. Prior to researching, the A&P had thought that some degree of a dent was allowable. After looking into it he has come to the conclusion that basically no dents are allowable and that the dented struts will need to be replaced. If this is the case, except for Bill B’s thoughts about additional components that I agree would be a good idea to have x-rayed, I will be looking for replacements struts instead of a testing entity. Has anyone had experience with dented struts? Any good or bad experiences with purchases of new sealed struts?

If there were no dents, with what I know today, I would have the struts, lower longeron clusters and strut attach fittings x-rayed every four years. The price would be worth the peace of mind to me. Whatever ends up happening with the struts I plan to look for the nearest location where I could fly to and have the lower longeron clusters and attach fittings x-rayed. Besides the peace of mind, it gives me another reason to go flying!

Blake

[Hank Jarrett]

Re: Strut ad

Don't trash the struts. There are ways to pull the dents out and I would like to know why a strut needs to be rejected because of any dents. As a structural engineer that doesn't make any sense. There has to be a limiting size and depth associated with the requirement. Rolling the struts from round to streamlined puts in hundreds of small dents. How big do they need to be before you reject the strut? Someone may be blowing smoke at you!
Hank

[VictorBravo]

Re: Strut ad

Applying the full force of my solvent-softened and under-educated mind to this issue, I have a faint, dim flicker of thought that an aero engineer might briefly tolerate...

Aren't wing struts primarily loaded in tension, which would make a minor dent sort of a non-issue?

On a Cessna Ag Wagon, which is a low wing strut braced design, I can see there being a question of the dent creating a risk of the strut buckling under compression.

On a clipwing T-craft flying 3 and 4 negative G maneuvers, you could make a case too.

But on a straight antique T-craft flying around right side up?

On the periodic table of the elements, on the far corner of the chart, is a rare and useful element found only in automobile supply shops... it's called Bondonium. It has properties which allow it to fill such dents and has the magical capability to make them essentially disappear.

IMHO this should be a question of dent size, depth, and more importantly the "sharpness" of the outer edges of the dent. WORST CASE scenario, a DER would have to run a couple of calculations on the dented strut's loss of compressive strength, compare those numbers to the rated negative G load of the airplane's original type certificate, and be done with it. My GUESS is that a minor dent in the strut would still leave enough structural integrity to meet the original TC negative G loading, which should end the discussion.

[VictorBravo]

Re: Strut ad

Someone may be blowing smoke at you!
Hank

Who's your A&P... Harry Ingram?