Fuselage strut fitting - FAA Airworthiness Concern Sheet (merged)

[tawadc95]

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

My grandpa,who was no Charles Lindbergh, took a half hour to preflight his hangared family cruiser every time even if he flew the day before. It seemed to work for him quite well as he started flying in 1927 and quit in 1994 at 86 with only one incident but never a mechanical one.My dad thought grandpa had the pedals and grandpa thought dad had the pedals and they ended going into a ditch during a rollout but that was it for grandpa in 67 years of flight.
I am not as patient as him and just can't take that long to preflight so I have started to post flight. I am still debating as to whether or not that is a good idea but herwe is why.I am always in a hurry to fly and never wanting to leave Sneaky when I am done flying, sooooo,I wipe her down real good and give her a thoruogh preflight for the next time. I like to wax in different areas for a bit as well as you get rather intimate if you wax.
When I go out for the next flight I look at the oil and for bugs etc in the cowl and drain the sump then it is off the terra firma.I would not do that if I was parked outside though...I only consider that safe enough for a hangared plane.

[DannyDot]

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

It looks to me like x-ray could do both the fitting and the strut at the same time, still on the aircraft...look at Bill's pics on the other thread... now THAT would be nice!
JH

Can you give us a link to these pictures?

Danny Deger

[Dano"T"]

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

Don't forget that float operations also cause greater stress concentrations on fuselage fittings than land operations....water at 50mph is like concrete, whereas land operations have bungees & tyres to absorb shock.

That's why the original fitting crack AD (back in God-knows-when) was quite sensibly restricted to floatplane operations.

Rob

I agree that there are occassionally conditions that make float landings and takeoffs harder on the airframe....but to assume that touching down on the water at 50 mph is like hitting conctrete is completely inaccurate....actually, under fair weather conditions with no waves....(like 99% of my landings on inland lakes) the landings are softer and put very little stress on anything.....it's those instances when the wind kicks up a chop that those stresses become an issue. I just want to set the record straight so people don't go assuming things that are not true....ask Mike Cushway(1938BF50) I took him flying and he was surprised how gentle the touchdowns were.

[Smithfield Slim]

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

The strut fittings are something we should all be checking during recover/restoration. I performed this inspection on mine back in 1969, after which I coated with epoxy primer; end of story.

Bruce Patten
N44184

[fearofpavement]

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

Well, I agree that a floatplane can touch down as smooth as silk and the passengers may not even know they have arrived yet. Conversely I have experienced conditions that would be somewhat akin to wheel landing a landplane across the furrows of a plowed field. I think what the posters are trying to convey is that in a floatplane the landing stresses, if there are any, are transmitted directly to the airframe as there is nothing else to dampen them such as tires, bungees, etc. Not that all landings are like hitting a wall. Thus, there will obviously be more stresses applied to the fuselage attach points. I believe that visual inspection will still identify any problems before they become failure issues, especially now that operators have their antennae up. This floatplane that had the failure may have been one of the highest time T-craft on floats ever, who knows? I don't feel that shotgunning the entire fleet with complex inspections is a viable solution.

[alwaysoar]

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

No offense intended here, but I don't think an inspection done in 1969 is the end of story. That was almost 40 years ago, and a lot can happen in that number of years. My plane was rebuilt in '99, and I plan to do a very careful inspection including Xray asap if I can find someone to do it.

[ClipWing_T]

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

The aircraft that had the fitting failure was poorly maintained. Some may say , not so , But I garuntee you we had an old AI here that WOULD have
found that corroded and rotten fitting on THAT airplane. He was slow and
thorough with his inspections too.....And a LOT of people wanted a pencil
whipped annual. To me the problem is one of poor maintainence and to
condemnthe whole fleet seems unecessary . The AI that signed that plane
off has to look in the mirror knowing he didn't do a good enough job. Maybe
he thought a 1969 sandblast and epoxy prime was the END OF THE STORY!
Might be in your case but it sure as hell wasn't in the failed aircraft we have
been talking about . Of course a hangared airplanes fittings are perfect in
most cases. But what about airplanes that are not?
Mike

[Forrest Barber]

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

I hope I have caught up on my reading, what a wealth of information is contained in these threads. Yes, Bill and others, we know that C.G. even commented to me at a Fly-In way back when I was wringing out the Taylorcraft that this was an "old airplane" and to be careful!!
BAck in the 50's we "recovered" many ships , then in the 60's we "recovered" again. At that time Irish Linen was used to extend the life of the fabric. Then we ahd Eonite , Ennox, Fibraglas, Dacon, Nylon, and many others;
some was approved to be applied right over the old covering ( no good inspection of the interior) , YES right over rotten cotton.........
Then we had Ceconite, Polyfiber, Blue River and many other processes my spelling may be wrong on some. THEN Mr. & Mrs. Feris developed the Taylorcraft process Randolph dope and dacron process, some ships were ordered special with Fiberglas or other ways..... In the 1970-80 era we did more than "recover" we started to "rebuild" then "restore" and now darn near build from scratch..... "Aging Aircraft" is indeed an area that needs a lot of study. Be careful out there and inspect, inspect, inspect.... cracked spars do show up. It is amazing the things that are found during restoration that are not desiminated to us all.

[Dano"T"]

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

Well, I agree that a floatplane can touch down as smooth as silk and the passengers may not even know they have arrived yet. Conversely I have experienced conditions that would be somewhat akin to wheel landing a landplane across the furrows of a plowed field. I think what the posters are trying to convey is that in a floatplane the landing stresses, if there are any, are transmitted directly to the airframe as there is nothing else to dampen them such as tires, bungees, etc. Not that all landings are like hitting a wall. Thus, there will obviously be more stresses applied to the fuselage attach points. I believe that visual inspection will still identify any problems before they become failure issues, especially now that operators have their antennae up. This floatplane that had the failure may have been one of the highest time T-craft on floats ever, who knows? I don't feel that shotgunning the entire fleet with complex inspections is a viable solution.

Agreed...I was just trying to avoid everyone thinking that every water landing was like hitting concrete.

[N96337]

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

Can you give us a link to these pictures?

Danny Deger

Danny, they're on the strut inspection results thread.
JH

[lfries]

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

E Mailed Andrew last night. Found out this morning the only AMOC is for Univair Struts. Felt confident that by weeks end I would have the eddy
current tesing done on the struts and the attach fittings. Then found out the IA I hoped to use is only authorized/certified to do eddy current testing on Air Tractors and Thrushes. May wait to see if there are AMOC's on testing between now and 11/20 before I search for testing facilities. I'm located in Central Calif. The IA did state that he would research the AD and see if
there was any possibility of him being able to do something.

[VictorBravo]

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

Then found out the IA I hoped to use is only authorized/certified to do eddy current testing on Air Tractors and Thrushes. May wait to see if there are AMOC's on testing between now and 11/20 before I search for testing facilities. I'm located in Central Calif.

LA X-ray here in Los Angeles did our X-ray inspection. It's only a two hour flight or less for you, it can be arranged so you can fly-in and fly out the same day (assuming you can leave the struts on the airplane). The LA X-ray company does Eddy Current, X-ray and other NDT. There is a probability you can come in, have them do the Eddy Current or X-ray, eat lunch, and fly away the same day. He did five of our planes on one Saturday. Contact me if you want to pursue this.

[VictorBravo]

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

Pursuant to a comment I made on the Strut Results thread, I put my money where my (ample) mouth is and wrote out a first draft of a SUGGESTED inspection criteria for the impending lower fuselage fitting inspection.

I do believe that WE here in this group should have the most say, and WE here in this group should assume the leadership role while we can.

Attached is my suggested procedure that IMHO should be presented to the FAA and used as a service bulletin, AD, whatever. Because I amNOT the most experienced, NOT an engineer, and NOT an IA, I would like to ask that those who are more qualified than I do their part and offer up suggestions on what should be added or removed.

The particular terminology and types of X-ray and Eddy Current are left blank, and need to be filled in by those who have the knowledge and experience in this area.

This inspection is very thorough on purpose. It represents going the extra mile to make sure that everything associated with this fitting and other related areas are looked at closely. These airplanes DO NOT get looked at as much as they should and it is a miracle that they have service lives this long. We need to start looking a lot more closely folks.

Bill

[Guest]

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

E Mailed Andrew last night. Found out this morning the only AMOC is for Univair Struts. Felt confident that by weeks end I would have the eddy
current tesing done on the struts and the attach fittings. Then found out the IA I hoped to use is only authorized/certified to do eddy current testing on Air Tractors and Thrushes. May wait to see if there are AMOC's on testing between now and 11/20 before I search for testing facilities. I'm located in Central Calif. The IA did state that he would research the AD and see if
there was any possibility of him being able to do something.

Can you elaborate? What is the AMOC you are describing?

Thanks, Dave

[lfries]

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

Alternative Method of Compliance.
Here is what he said
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.