Warbird Information Exchange

Hi all

I know this topic was raised a couple of years ago by Matt, but am interested to know if new T-6 wing attach angles have ever been reproduced? I know that new old stock wing attach angles are (or were?) still available, but has anybody made or considered making new ones??

From my experience 60 year old 2024 just isn't the same as new material.

Thanks for any info.

Jason

Not sure about the production of replacemebr attach angles, but I'm almost certain that none have ben produced in recent years. I'd be happy to be proved wrong however!

We're after a set of servicable attach angles for the wing centre section, both top surface, lower surface and those fitted to the stress pannels. We also need a set of lower attach angles for the outer wing panels (we have to surface angles), both left & right.

I know that Lance will have some, but does anyone know of any other suppliers?

Thanks,

G

_________________
BURMA! Sorry, I panicked

Contact Midwest Texans. I think they're making new ones.

Gary

Were working on it, but we don't have them yet...soon, hopefully.

I was out at Nelson Ezell's place in Breckenridge last week to look at the P-38 and noticed a T-6 wing in a Jig. The gentleman working on it said it was a newly fabricated wing. The Jig is set up to fabricate both Left and Right wings. Maybe they are making the angles too. You might contact them.
http://www.ezellaviation.com/

Tim,
When the new ones are made, will they be subject to the AD or not? Thanks.

I believe it's a reaccuring AD not just a one time thing.
I don't recall a clause in the Ad referencing new built units.

_________________
Don't touch my junk!!

In our prelminary discussions with the Aging Aircraft folks at the FAA, the AD would not apply to new angles, at least not until 10k or so hours. This is of course all subject to their final approval. Our goal, however is to eliminate the AD.

Any even bigger issue beyond the cracking AD is the corrosion problem. When we pull wings and center sections part, which we do on a weekly basis, we invariable find corroded angles. In fact, we recently rebuilt a wing from an accident and when we went to reinstall the angles found two bad ones of the two that we removed to fix the damage. Not from stress cracks mind you, but from intragranular corrosion. In my opinion that is a much greater problem with these parts than stress or fatigue.

When Tim gets his new angles approved, he would apply for an "Alternate Means of Compliance" to the AD to the small airplane directorate in Wichita for an approval to clear any re-occuring inspections of the angles.

Simple to do actually, just have to have the engineering data for the new angles to show that they are equal or better than the original.

I know the eddy current is a alternate inspection method for the AD.
Can a good operator pick out corrosion when inspecing for crasks
in the angels??

_________________
Don't touch my junk!!

Very much so, eddy current is a great way of inspection in the right instance.

I am not expert on NDT or eddy current, but I do know that we have seen a lot of angles come through the doors that have passed eddy current, but we have found corrosion on them when we have removed them. Could just be a situation of bad operator etc.

The problem now with NDT (non-destructive testing) is that the technology is getting so good that small original manufacturing anomalies that really are not a problem are causing problems after inspection in todays world.

We had spar carry-thru on a Cessna Citation 560 that had been eddy current inspected for years and passed. Cessna incorporated a new type of eddy current inspection and it pinged a problem area. We reamed out the attach hole several times until we got to a stop point and did not want to go any further.

I eventually brought in an engineer who's specialty was damage tolerance to analyze the this and write a new inspection criteria for this particular area. Of course the Damage Tolerance analysis showed it needed to be inspected every 10k cycles or 8K hours which exceeded the original inspection criteria from Cessna.

We saved the aircraft owner from having to replace his spar carry-thru structure, which is a huge if not impossible job.

That is usually the case. NDT professionals that are approved by the OEM can be too good to a fault. See above!

The AD only calls out to inspect the bolt holes, not the rest of the angle so you won't find anything where you aren't looking! Eddy Current should pick up intergranular corrosion internal to the attach angle, but surface corrosion between the skin and the angle would not likely be detectable unless there was exfoliation.