Strut Airworthiness Directive (AD) (merged VI)

[Ragwing nut]

Re: Strut Airworthiness Directive (AD)

Where does it say that, Mike? I was always directed to 21.303 (b) (2). As long as it's not for sale, but will be used on your aircraft, you can do it.
JH

That is correct. Struts are available through Univair and soon the factory so they can't be produced under 21.303. As long as it is not being produced you can make it under 21.303 for your own use.

[M Towsley]

Re: Strut Airworthiness Directive (AD)

Bob Picard,

My L-2B's struts are probably from some other source as the front one is much larger than a stock L-2. The plane was also completely rebuilt in '93. The struts also appear to be 'sealed' as I cannot find any drain holes. However, I will be taking Dave's hints to look around for any unsealed portion. Also, Forrest let me know the FAA is contacting the current TC holder for the L-2's, (Pima Air Museum). So we will see what they do with ours.

[LostnSpace]

Re: Strut Airworthiness Directive (AD)

Hey gang, I'm sure glad we have this forum to share ideas. I'd be lost without it.
I just went and inspected my L-2B and after looking very closely I can't for the life of me find any vent holes anywhere on any of the struts: top, bottom, fore and aft. Nothing nada zip. The way they are welded it appears that they are indeed sealed. According to the log books dating back to the '50s, they have never been replaced. Is it possible that (part numbers aside) the L-2B struts were made differently and that is why they were left out of the AD? Are the L-2B struts interchangeable with the other series airplanes? Since the struts are easily removed I am considering taking one with me SCUBA diving and see if I get any air bubbles at 30 ft. Any comments?

It has been about 3 months ago, before all this strut hopa, I was helping install the wings on an L-2B and took a blow nozzle and blew air in the bottom end of the front strut and could hear it coming out the top end, the L-2 strut has a square end where it attaches to the fuselage and then the rear strut bolts to a flat plate that is welded to the front strut, making it different than the BC12 and others, but why is a TG-6 conversion in the applicability section, isn't a TG-6 conversion have the same struts as the L-2?, best to you, LNS

[alwaysoar]

Re: Strut Airworthiness Directive (AD)

This AD is a PIA and is pretty much killing my interest in old airplanes. I bought new front struts from Univair this spring and as I read the AD "equivalent" FAA approved struts are exempt from the AD. Where in the H--- am I going to find a place to xray around Vermont for my aft struts? After the initial, that I have done (incidentally, it is possible to look inside the unsealed aft struts with a b-scope--any comments on that?), however, we have three months from Aug 20 to get it done, and hopefully by that time an AMOC will be approved such as the Piper method of compliance.

These are great planes, but a case in point for going X

Ed@BTV VT
TF 527

[VictorBravo]

Re: Strut Airworthiness Directive (AD)

Any seaplane guys, or people familiar with the Wiley seaplane crash...

I have a question on the potential lower fuselage structure AD. Was the seaplane crash due to corrosion from the iNSIDE of the longerons and into the fitting, or was it water trapped betwween the fabric and the OUTSIDE of the longerons/fitting?

In the typical corrosion scenario, water in the fuselage gets between the fabric and the steel tube and attacks the tube from the outside. This can be visually inspected, punch tested, etc. fairly easily.

If there was a situation where water got into the inside of the tubes and corroded them from the inside, then of course the outside of the tubes would appear airworthy long after the tubing had been compromised.

The reason I ask is that I have Univair front struts, so the strut problem will not be a big issue for me, my exposure is limited to inspecting the rear struts. However the potential fuselage structure inspection is a different story. I have a pre-war airplane that has spent time in the NW USA. I just looked at the strut attach area lying on a creeper, and it all looks peachy from the outside (through the paint), and I poked at it with a little punch in a few places... but I realize this i not a thorough inspection.

[N96337]

Re: Strut Airworthiness Directive (AD)

You can't build new struts or any other part under 21.303 as long as the part is being manufactured either by the manufacturer or an approved PMA process.

Mike

Where does it say that, Mike? I was always directed to 21.303 (b) (2). As long as it's not for sale, but will be used on your aircraft, you can do it.
JH

Re: Strut Airworthiness Directive (AD)

Hey gang, I'm sure glad we have this forum to share ideas. I'd be lost without it.
I just went and inspected my L-2B and after looking very closely I can't for the life of me find any vent holes anywhere on any of the struts: top, bottom, fore and aft. Nothing nada zip. The way they are welded it appears that they are indeed sealed. According to the log books dating back to the '50s, they have never been replaced. Is it possible that (part numbers aside) the L-2B struts were made differently and that is why they were left out of the AD? Are the L-2B struts interchangeable with the other series airplanes? Since the struts are easily removed I am considering taking one with me SCUBA diving and see if I get any air bubbles at 30 ft. Any comments?

The absence of vent holes alone does not make them sealed neither does the welding.

They have to have been coated with linseed oil or equiv. when manufactured and also they need to be sealed at the bolt hole locations.

Look at the rear strut- is the adjusting tube hollow or does it have a cap welded on the end so it looks solid? Hollow means not sealed.

Take the top bolt out the front strut, look in the strut bolt hole. Is it a straight thru hole thru a sleeve or can you access the middle of the strut tubing from the bolt hole, ie no sleeve around the bolt. If you can access the tubing center from the hole its not sealed. Use a pice of safety wire as a test probe.

[n6346m]

Re: Strut Airworthiness Directive (AD)

Hey gang, I'm sure glad we have this forum to share ideas. I'd be lost without it.
I just went and inspected my L-2B and after looking very closely I can't for the life of me find any vent holes anywhere on any of the struts: top, bottom, fore and aft. Nothing nada zip. The way they are welded it appears that they are indeed sealed. According to the log books dating back to the '50s, they have never been replaced. Is it possible that (part numbers aside) the L-2B struts were made differently and that is why they were left out of the AD? Are the L-2B struts interchangeable with the other series airplanes? Since the struts are easily removed I am considering taking one with me SCUBA diving and see if I get any air bubbles at 30 ft. Any comments?

[Ragwing nut]

Re: Strut Airworthiness Directive (AD)

If you want to build your own struts under 21.303b2, you would have to get a 337 and the required engineering data to prove they meet the same spec as the Factory parts. or no dice on getting them approved, its more money for the data than to just buy the part. There is nothing about the END CAP, the reason to remove the struts is to prevent false indications. Tim

You can't build new struts or any other part under 21.303 as long as the part is being manufactured either by the manufacturer or an approved PMA process.

Mike

[LostnSpace]

Re: Strut Airworthiness Directive (AD)

.

Also, what is the number on the cub AD. I would like to look it up.

99-01-05, have fun. LNS

[DannyDot]

Re: Strut Airworthiness Directive (AD)

I replied on that dot docket as well....I also said why can't we inspect the same way as Piper Cubs.....wht's good for the goose is good for the gander.....if it's safe for a Cub then it's safe for a T-craft IMHO

I just used the online comment capability to recommend Taylorcrafts be allowed to use the Piper Cub approved inspection method.

Danny Deger

[DannyDot]

Re: Strut Airworthiness Directive (AD)

Whats the deal, why can't we get them inspected the same as I do all the time on cubs, using x-ray, the guys come out and do it right on the plane for 175.00 and then they tell me what the thickness of the strut is and if there is any places that are rusted. I've got a F-19 in the hangar right now and thought I was done with the annual, now I've got to deal with this or have the guy come back. I've had t- craft struts x-rayed before, just to see if they would past and they did, the wall thickness on T-crafts are heavier, than cubs, but I been thinking its only a matter of time before this would happen. I guess I'll call the testing guys and ask them if they can do this type of testing, I've had T-craft owners calling me all day to find out what to do.

Can you call the FAA engineer, Andy McAnaul, (210) 308-3365, on this technique and post back here what you find? If there is a $175 x-ray test for wall thickness, I don't see why we can't use it. If you look at the Service Bulletin it is clear that the purpose of the test is to measure wall thickness. In my conversation with Mr. McAnaul it appears that the FAA just went with the SB as a first cut, but is willing to listen to other ways to make sure the strut is not corroded.

Also, what is the number on the cub AD. I would like to look it up.

Danny Deger

[Dano"T"]

Re: Strut Airworthiness Directive (AD)

I replied on that dot docket as well....I also said why can't we inspect the same way as Piper Cubs.....wht's good for the goose is good for the gander.....if it's safe for a Cub then it's safe for a T-craft IMHO

[DannyDot]

Re: Strut Airworthiness Directive (AD)

Right, agree, but it appears that Danny has found out that the FAA engineer is willing to rescind the off the plane portion of it. I like that.

More of us should submit that comment.

I just used the on-line comment capability at http://dms.dot.gov. The AD is called Docket No. FAA-2007-28478 on this site. The process was very simple. I recommend we all comment on changing the AD to allow for on the plane inspection.

As I said, I don't know how good the guy that did my recent recover looked over everything, so this time I am going to pull the struts, inspect everything and coat the inside of the struts with oil. In 2 years I will probably see some of you at an inspection/fly-in and get it done on the plane.

Danny Deger

Re: Strut Airworthiness Directive (AD)

The "real reason" for removing the struts is because the AD staes "Follow....Service Bulletin..."

Right, agree, but it appears that Danny has found out that the FAA engineer is willing to rescind the off the plane portion of it. I like that.

More of us should submit that comment.