Reasonably priced strut inspection

[paulnuss]

An FAA-certified eddy-current lift strut testing service for the AD-affected Taylorcraft lift struts is being considered, at the cost of $35.00 per strut. The testing location would be in Dayton, OH, and would include a certification of inspection, by a repair station that has considerable experience with non-destructive testing procedures for FAA compliance. The price offered is contingent on enough Taylorcraft owners and mechanics committing to the testing procedures to justify the set-up (I was told at least ten sets of struts would be the bottom threshhold). This price would be for testing only and certification of the inspection, and would include no other services (which could be available at a negotiated price). I for one am interested, and have put my name first on the list.
Univair has no struts available right now; I'm more than reluctant to send money to the "factory" under its current regime. For further information call Jon Molek at (330) 299-1056.

[Larry Lyons]

Re: Reasonably priced strut inspection

I have set off right now ready for such an inspection. I will not need them for 3 or more years but it would be nice to know if they will work or I need new. If this is acepted by the "powers that be" put me on your list. I will hand deliver them. I may have a second set but will need a few days to confirm. Larry

[cpirrmann]

Re: Reasonably priced strut inspection

Will they accept them off the plane (shipped or hand-delivered) ?

[gilligansae]

Re: Reasonably priced strut inspection

I would be willing to drive to Dayton from Rochester- take as many people's struts as needed- put them all in a U-haul and go so we can all get this done and out of our hair......If it is going to be as low as 35 per strut count me in right now, set the date, i will be there.

Jeff LaChausse
585 764 4198

[crispy critter]

Re: Reasonably priced strut inspection

Count me in on that one too. I'm in east kentucky and I can take a load of them if you want to get them to me.Just make sure they are set up and ready to go before you start sending me struts.

[paulnuss]

Re: Reasonably priced strut inspection

The information I was given is that the struts must be off the plane. If you need the services of a mechanic to assist in doing that, perhaps Jon Molek the contact could assist, depending on location. He is a licensed mechanic and familiar with Taylorcrafts. All inquiries should be called to him at the phone number given (330) 299-1056. Please be aware that I am not involved in this service in any way, I am only passing on the information because I thought it might be useful to other Taylorcraft owners.

I figured on gathering my own struts and perhaps those of a friend or two here in the west-central Pennsylvania area and driving them out to the Dayton, Ohio area when he is ready. Anything more I find out, I'll pass on to you all.

And, that will give me two years (assuming mine pass inspection) to address the next step, continually test or replace.

[hangarb7]

Re: Reasonably priced strut inspection

I am in Southwestern Pennsylvania, and I would also be interested in participating. My struts are still on the airplane.

I know of one other TC on my airfield and with all the airports in this area, there are undoubtedly many more. I have no doubt we could get ten sets from this area alone.

Driving to Dayton would not be a problem and /or I could remove them and ship to where ever. Put my name on the list and hopefully we can get this accepted.

Just don't make the meeting date too soon after acceptance. Need a little time to react as I am not always in town.

Thank you.

Jack Dernorsek
N44057
'46 BC12D
FWQ Rostraver Airport

[barnstmr]

Re: Reasonably priced strut inspection

CAUTION - Eddy Current Inspection not repeatable - poor method

Before making your decision, please read below.

Yesterday, a group of us in Central TX traveled to San Antonio to visit a long-established NDI lab. BRL Consultants. Our objective was to develop a cost-effective way to deal with this strut AD and to do so in a way that produced the best results. We took 2 sets of Taylorcraft struts. Brian Lancon, an experienced NDT professional for more than 20 years and owner of the company graciously gave us 3 hours of his time and demonstrated 3 different means of NDI on these parts. We learned much during this visit and are preparing a thorough report for presentation to the FAA and to share with this forum.

The BRL Consultants Lab is within one mile of the FAA office of Andrew McAnaul, however he was unavailable for this meeting. Perhaps he will be able to visit soon. In brief, we learned and confirmed the following. I am sure some of the others who participated have more to report than me. I am just providing a brief overview.

1) Eddy current method was demonstrated and was found to give undesirable results. As a means to measure steel material thickness, it is not repeatable.
2) Radiography was demonstrated and was found to be by far the BEST method to see the general condition of the struts. This method shows variations in density. Of the 4 struts off of my airplane, one showed an obvious area of rust near the vent hole. This method pinpointed the suspect area with an UNMISTAKABLE IMAGE of rust (a dark spot much like tooth decay would show on a dental X-ray), however it was not sufficient for detecting the thickness of the material.
3) Ultrasonic inspection was then used to further interrogate the suspect area found by the X-ray. This hand-held device worked best with paint removed. The suspect area measured 0.041 whereas the non-corroded area measured 0.042 (average of three random locations on the exterior).

CONCLUSION - Recommendations
We will provide a full report to FAA recommending a procedure including #2 and #3 above as a preferred means of inspection. BRL consultants has agreed to assist in review and input on this report. Also, based on the quality of the X-ray images and Ultra sonic measurement, it is reasonable to recommend that (after initially establishing sufficient wall thickness exists and if properly treated with corrosion inhibitor) a much less frequent time frame be used for follow up inspection.

COST -
Brian Lancon, BRL consultants, estimates the cost for #2 and #3 above to be less than $200 for struts measured in his lab this way. In order to keep his time and cost down, he recommended that the struts come in with paint removed.

It was established that it is not feasible to do this kind of thorough inspection on the aircraft, but it is possible to do at a higher cost.

Mark, Rick and others... chime in to add your comments and conclusions from our trip yesterday.

REQUEST FROM OTHERS INTERESTED AND DOING NDT INVESTIGATIONS
This effort is to benefit us, the owners. If any of you have done similar investigations on your own and have images or results to share, please forward them to us. We can include this in our comprehensive report and perhaps provide proof and emprical data to the FAA as justification to lessen the impact and cost of this AD.

Let's join in this effort together.

[barnstmr]

Re: Reasonably priced strut inspection

I will post some X-ray images soon... but need to learn how to post fairly large images like some of the guys do on here.

[Ed O'Brien]

Re: Reasonably priced strut inspection

Terry;
By your above described test -- Your results? This was the "feeling" of many of us. However, you're the one that did it right and confirmed it imperically. Nice job and collectively we owe you our gratitude.
With regards;
ED OBRIEN

[barnstmr]

Re: Reasonably priced strut inspection

There was also help from others... Mark Julicher, Rick ___, Lon Carr, and my son Travis. Not done yet, either... more work to do.

Mark J, please post your write-up to the group. It was very well written.

[Ed O'Brien]

Re: Reasonably priced strut inspection

Might I suggest a follow-on idea. For those that have corroded struts... do NOT throw them out. Write up a
paragraph from your logs regarding time on plane, condition of strut, ... how much time in hangar v how much time on tie-downs. Keep both the log and the strut and wait a few month until this thing settles down a bit. I think either the PMA/Factory or the FAA might be interested in several (many) destructive tests.

Remember unlike the B-52 which has a full sized version in permenant static flight in a hangar in Wichita, KS. being loaded and unloaded with water and sand bags mechanically flexing each wing since 1953... flying 24/7 and is now approaching 500,000 hours of virtual flight. This so Boeing can predict failure points... our planes have not such predictor. We are our own canaries in the mines shaft. We are our own test pilots, aviation reporters, and aeronautical thinkers. We are literally the living breathing embodiment of CG Taylor. And while I'm not a believer in Astral Projection or ghostly habitations... I believe in this.

I'm thinking eventually we may all want new struts, eventually... and perhaps those should painted/dressed/ primed on the inside. Anyway -- everything we do that is done well -- every step we take -- is good for aviation in general and good for us too. Terry Bowden and Mark Jelhniker NST tests are a perfect example. Thanks Guys!!!
Thanks to all and deeply so.
With regards; ED OBRIEN

[flyguy]

Re: Reasonably priced strut inspection

Very professional Terry. Well done. Confirms my experience and what I have read about the testing processes and equipment used.
Question: Was there any discussion by the test people of whether linseed oil or other anti-corrosion material will affect the radiographic results?
Darryl

[barnstmr]

Re: Reasonably priced strut inspection

Here is the beauty of radiography... BRL Consultants has re-usable film plates that are really the key to keeping the cost down. Find a shop with this capability if you can. By re-useable, I mean that the image is transferred to the plate, which can then be loaded into a scanner device.
The scanner digitizes the image for reading on the PC. Images can then be enhanced, zoomed, etc... then saved as regular jpeg images.

This is truly the only way to go in my mind. You can see inside your struts and know what you've got.

Notice that the smaller image is zoomed and enhanced in an area that showed to bw suspect on the larger image.

[barnstmr]

Re: Reasonably priced strut inspection

Here is Eddy Current

Readings of the same test plate six times...each time different signature. Not repeatable.