Strut Airworthiness Directive (AD) (merged VI)

[Forrest Barber]

Re: Strut Airworthiness Directive (AD) (merged VI)

"that" refered to a fellow way back on this thread asking if he could do the inspection himself , I think that is now clear; NO!
I have been in daily contact with The FAA engineer McAnaul and we review your valuable comments. Yes he told me two days ago that the Univair situation will be resolved. Univair had a problem with "applicability" from day one. It will now be resolved so that those part #'ed struts CAN be used on all models. Then we ahve the Alaska Repair Station doing struts and perhaps Wag-Aero. At the moment , if the factory can produce, they need support too!! BUT , let's inspect according to the AD and determine IF there is a problem. The pending SB on the strut attach point is my other concern, many thoughts are coming in..... they need sorted out. I have another call into the inspection service up here.... www.usinspection.com with many more questions. Keep the info coming in and fly safe out there.

[Guest]

Re: Strut Airworthiness Directive (AD) (merged VI)

"that" refered to a fellow way back on this thread asking if he could do the inspection himself , I think that is now clear; NO!
I have been in daily contact with The FAA engineer McAnaul and we review your valuable comments. Yes he told me two days ago that the Univair situation will be resolved. Univair had a problem with "applicability" from day one. It will now be resolved so that those part #'ed struts CAN be used on all models. Then we ahve the Alaska Repair Station doing struts and perhaps Wag-Aero. At the moment , if the factory can produce, they need support too!! BUT , let's inspect according to the AD and determine IF there is a problem. The pending SB on the strut attach point is my other concern, many thoughts are coming in..... they need sorted out. I have another call into the inspection service up here.... www.usinspection.com with many more questions. Keep the info coming in and fly safe out there.

Thanks for the clarification Forrest, Dave

[Forrest Barber]

Re: Fuselage strut fitting - FAA Airworthiness Concern Sheet (merged)

We had the visit here in Alliance at 2D1 today from Michael Cooper & Darrin Vaughan from the Acuren Company. www.acuren.com . they bought out
usinspections that I had contacted first up here in NE Ohio for NDT.
They took one look at the situation and are going back to the office to start develop the procedure etc. for a Digital Radiology test that may allow us to look at the strut ends and the attach fitting same as Bill Berle had done on the West Coast. Acuren is all over the country even Alaska doing work on big ships, pipelines, NASA etc. They have Repair stations all over.

Sorry to move so slowly but myself , the factory, other STC holders and other experts along with the the FAA engineer McAnaul are considering many things. Mr. Ingram & I have talked quite a bit too!

I do not know if this is for release but since we are such a small group I hope we can work together. I have been told that the NTSB report on the Wiley accident is forthcoming, Mr. McAnaul is re visiting and considering the Maule test and to maybe extend the time situation if results of pre-liminary testing show a lot of good struts. I will be away tonight & early tomorrow. More then. thanks Forrest
Bill I will comment on your procedure directly to you.

[Robert Lees]

Re: Fuselage strut fitting - FAA Airworthiness Concern Sheet (merged)

Mr. McAnaul is re visiting and considering the Maule test

I can't comment directly (things said in confidence, etc), but it sounds like the FAA are listening to EASA (who are responsible here in Europe).

This post will self-destruct and be re-directed the the "Strut AD" thread in three days.

[flyguy]

Re: Fuselage strut fitting - FAA Airworthiness Concern Sheet (merged)

"Mr. McAnaul is re visiting and considering the Maule test and to maybe extend the time situation if results of pre-liminary testing show a lot of good struts."

Well, that is good news.
DC

[lfries]

Re: Fuselage strut fitting - FAA Airworthiness Concern Sheet (merged)

Just a Question. I asked for approved AMOC's along with procedures to get an AMOC. I received an immediate reply. Then I asked for supporting Independent analysis for the AD and no response. Has anyone been able to get this information from the FAA.

[Guest]

Re: Fuselage strut fitting - FAA Airworthiness Concern Sheet (merged)

Just a Question. I asked for approved AMOC's along with procedures to get an AMOC. I received an immediate reply. Then I asked for supporting Independent analysis for the AD and no response. Has anyone been able to get this information from the FAA.

Can you post the list of AMOCs they sent?

[lfries]

Re: Fuselage strut fitting - FAA Airworthiness Concern Sheet (merged)

Here is the response I received.
"The only AMOC granted to date is to Univair stating that installation of
> their Part Number UA-A815 and UA-A845 sealed struts in BC12-D/D1 airplanes > provides a equivalent level of safety to be considered as terminating > action for the AD. If you have these parts on your airplane you do not > need to take any additional action for the struts.
>
> We have not issued any relief from removing the struts to comply with the
> AD. Removal of the strut allows for inspection of the attachments and
> fittings, and facilitates applying preservative into the internal strut
> cavity which is a required corrosion retreatment as part of the inspection
> procedure in the Service Bulletin."

Comments on the forum today make it look like there may be other AMOCs coming. The above was sent Sept. 10.

[Forrest Barber]

Re: Strut Airworthiness Directive (AD) (merged VI)

During the comment period, many ideas are proposed. If they have supporting data that is "acceptable" at best to the FAA then a AMOC or time extension can be added , know as a "revision" please have a a reputable IA sit down and explain this procedure. YOU the owner are responsible for the "airworthiness" of your aircraft. You have to use an approved method of doing this ..... A&P , IA , TC holder, PMA'd items, STC'd, "owner produced" . back to the grind at the airport today.

[Merlin1650]

Re: Strut Airworthiness Directive (AD) (merged VI)

Hi all,

This thread is getting alot of action which is great. I'm a late joiner but I could do with some help.

In New Zealand I have the only BC-12D (and only fabric taylorcraft) and most engineers are unsure about this AD. I've looked at my own lift struts and appear to be completely sealed. But I'm unsure. Are un-sealed struts defined by having a simple drain hole or are they completely open ended like a citabria? If i can get some guidance on what to look for that will be great.

Also I can't find any numbers (Part or Serial) on the struts. Where should the numbers be?

Cheers
The Kiwi

[Guest]

Re: Strut Airworthiness Directive (AD) (merged VI)

Hi all,

This thread is getting alot of action which is great. I'm a late joiner but I could do with some help.

In New Zealand I have the only BC-12D (and only fabric taylorcraft) and most engineers are unsure about this AD. I've looked at my own lift struts and appear to be completely sealed. But I'm unsure. Are un-sealed struts defined by having a simple drain hole or are they completely open ended like a citabria? If i can get some guidance on what to look for that will be great.

Also I can't find any numbers (Part or Serial) on the struts. Where should the numbers be?

Cheers
The Kiwi

Use the search function at the upper right portion of the window and search for "sealed" press the bottom for listing posts rather than threads and you will find your answer.

There are no serial numbers or part numbers on struts, its a sales gimmic from t-craft.

Dave

[Len Petterson]

Re: Strut Airworthiness Directive (AD) (merged VI)

In "testing" my struts with sounding by a light hammar blow, they "ring".
No cracks are visable and I will ask my AME to do a maule test and I will let you all know what we find. I belive my struts would pass any test.
A check on the strut mount will also be dune.
We check the strut mount last year and found no soft spots using an awl but you don't want to brake the painted surfaces on the fuselage tubing either.
It would be nice if a Mauletester could be used.
A Canadian Aircraft.
Len

[Hank Wehrli]

Re: Strut Airworthiness Directive (AD) (merged VI)

I was shown about 5 years ago at the annual T_Craft fly-in in Alliance that the "Ring Test" was a "good" way of establishing the air true condition of the struts. In fact the guy actually used his wedding ring to show me that my struts were "great" as judged buy the sound test of the response that he got. I'm sure the FAA will not agree to something so simple but there must be something between this "test" and a full NDT expensive procedure that can be agreed upon. This is especially important if unsealed struts must be inspected every 2 years.

Think Safe and Cheap

Hank Wehrli
N2003L
The last F19 ever built!

[Hank Jarrett]

Re: Strut Airworthiness Directive (AD) (merged VI)

Len,
When I was working with the NDI floor guys the "ring" test was just a first step. Lots of parts could be hung from a piece of coat hanger and tapped to see if the rang like a bell. If it rang, that DIDN'T mean there were no cracks! We still had to do a full dye penetrant, mag particle or X-Ray. If it made a dull "thud" when tapped it we almost ALWAYS found a crack, usually a BIG one. A lot of times a quick visual of a "thud" check failure would show a crack without NDI and save some time and money, but we NEVER passed a part on the basis of a ring! The ring comes from vibration in the part and a crack oriented right will still ring with a crack. The ring check just filters out the really bad (probably) ones.
Hank
By the way, don't trash it just because it "thuds" either. We had a bunch of tap failures in a row once and it was traced to a coat hanger with a plastic coating that damped out the vibration. DOH!!!

[Mark Julicher]

Re: Strut Airworthiness Directive (AD) (merged VI)

Terry Bowden (Barnstormer) and I met with Joe Perez at the Bowden's airport (69TE "Deer Pasture") Friday August 14th for about three hours. Joe is the maintenance inspector that works directly with Mr. McAnaul here in San Antonio. The meeting was very positive in all respects.

As many of the tribe already know, Terry and I took two sets of struts to a NDI Level III shop and did Eddy Current, X-ray, and Ultrasound. Those results were posted by Terry.

Joe looked over Terry's BC12-D which had the struts off (and dripping linseed oil in the corner). Joe showed us more photos of the seaplane crash and we discussed the general state of Taylorcraft maintenance. After this more-or-less chit chat I asked Joe several direct questions. The answers below are paraphrases not direct quotes.

Question 1: Why is the inspection interval two years? If the struts look good upon inspection then couldn't the NDI interval could be longer?

Answer: It could possibly be longer. As more field data is available and the FAA gets a better picture of the state of the Taylorcraft fleet the interval may be extended; however, after the accident the thinking was to do something safe and expeditious which resulted in the current AD.

Question 2: What about AMOCs? Will there be something possibly less expensve?

Answer: AMOCs are definitely in the mix. X-ray will most likely be part of the solution. The small aircraft directorate is not pleased with making the AD prohibitively expensive. The FAA is very sensitive to the expense to the aircraft owner.

Question 3: Eddy current is not normally used on ferrous material because it gives inconsistent results. Will eddy current remain as a preferred NDI technique?

Answer: The chief NDI specialist for the FAA has looked at the AD and some test results. The FAA recognizes that eddy current might not give the best indication of the condition of the struts or the wall thickness. X-ray followed by ultrasound will probably be an approved solution.

Question 4: What can you tell me about the lower fitting and how the FAA is proceeding?

Answer: Right now it appears that the seaplane crash was an isolated incident. There were many visual indications that there was significant rust in the fitting and stuts that could be seen during preflight. More field data is needed to verify that the incident can be considered isolated, although an inspection of the fleet may be called for.
_______

At this point Joe pulled up photos on his laptop showing a dye penetrant test of a lower fitting from a Taylorcraft that had been landed very hard. The dye showed a significant crack in the longeron, but the fitting was in good shape. Joe seemed to think that wear and tear would show up in other places before the fitting was damaged. Joe also had some ideas about how the fitting could be repaired. Joe works very closely with the factory as the cognizant maintenance inspector. Finally, Joe showed us photos from the factory of how the lower portion of a Taylorcraft fuselage could be removed (cut out) and replaced with a new assembly. The assembly would allow for field welding only at longerons and cross tubes while the assembly itself could be made on factory jigs to keep the lower fittings in alignment. This is an elegant solution, but personally I hope it will only be needed on rare occasion as it is a major effort to say the least.

I repeated an offer (from a month ago) to have the San Antonio FAA office come look at two Taylorcrafts (BC12-D and F-19) which I am rebuilding here in town, and also to make three other flying Taylorcrafts available for close inspection - all here in greater San Antonio.

So that is the news from Deer Pasture airport in Burnett, Texas.