Structural failure statistics

[cpirrmann]

Just out of curiosity, has anyone tried or been able to compile the stats involving Taylorcraft structural failure, esp. struts and attach points?
Not trying to start anything, just curious.

[cpirrmann]

Re: Stas

Just a little info I briefly compiled. I did a search of the NTSB records from 1/1/1946 to present. For all Taylorcrafts, the records apparently go back to 1964. I searched for any report involving 'strut' and they went back to 1983. The recent accident was not listed. There were no failures of struts in flight listed. In almost all, the struts were still attached even when the wing failed at the root.

Heres one interesting example:

"During the descent into the swamp, the pilot stated the airplane's right wing tip struck a tree causing the airplane to nose over into the swamp. The pilot reported the right wing spar was broken at the fuselage attach fitting, the right rear wing strut was bent, right wing tip bow was bent, and the right landing gear had crushed."

There was only one where a strut had failed in 1983:

"HE SAW TELEPHONE WIRES AHEAD THAT CROSSED THE LAKE & DESCENDED FASTER THAN NORMAL TO ASSURE A LANDING BEFORE THE ACFT GOT TO THE WIRES. SUBSEQUENTLY, THE FLOAT PLANE LANDED HARD & THE RIGHT FRONT STRUT FAILED. HOWEVER, THE ACFT REMAINED AFLOAT & WAS LATER TOWED TO THE SHORE."

Now, I'll stir something up, this isn't about safety. It seems to me, we're already doing the job pretty good.

[VictorBravo]

Re: Stas

Some of this is off-topic for this thread, but is somewhat related...

The "other side of the coin" on statistics needs to be addressed. Recently there was a big to-to about "best practices" in dealing with the aging aircraft fleet. The FAA, EAA, AOPA and lots of other organizations were involved. They put out a little pamphlet that basically said that most of the light aircraft flying are very old, and have been in service a lot longer than the designers intended them to be... so there needs to be much more attention paid to keeping them airworthy. The pamphlet specifically talked about newer and better and more thorough inspection methods.

As unwelcome as the FAA's most recent AD seems to be, the general idea that we need to start looking more closely and more frequently at our 60 year old airplanes is totally valid in my opinion. As per the specific thread(s) on the subject my opinion is that there needs to be changes in the AD, but we definitely need to be looking at our structures much more now than we ever did before.

Why?

First, the planes are old (duh). There were very few structural failures of covered "conestoga" wagons in 1865, and an AD would have been ridiculous even in 1900 based on statistics. However, if these same 1800's vintage covered wagons were still on the roads in 1940, they would have been all clapped out, rusted, and termite-infested. Anyone sharing the road (even lovers of Old West technology) would have agreed that you'd better take your antique covered wagon apart, re-glue it, check the welds or rivets, and put some more varnish on the wood BEFORE there is a statistic of your wagon falling apart... Maybe overhaul the horse while you're at it.

Second, there are hostile entities and people out there that were never there back in the old days. If a strut attach fitting pulled out in 1957 and an aircraft was lost, it would be a small blurb in a local newspaper and that would be the end of it.

If my struts pulled out today the accident would be used as fodder for any number of small time cockroach politicians who would use it as a bully pulpit to get themselves on TV (demanding that something be done to protect the public from this menace of rickety old airplanes).

The Right Rev. Al Sharpton would call a big press conference to say the crash was a clear attempt by a white man to oppress people of color. Hillary Clinton would try to get elected by claiming that she would redistribute the excessive wealth of the slimy rich Taylorcraft owners among the poor. The Ku Klux Klan would have a banana split field day, assuring everyone that if they were in charge this never could have happened.

And the NTSB, DOT, and FAA people would all have this horrible nightmare of losing their government pension if they didn't look very busy immediately.

Every light airplane crash today has the potential of driving a nail in the coffin of general aviation. Not on my watch if I can help it.

[cpirrmann]

Re: Stas

"As unwelcome as the FAA's most recent AD seems to be, the general idea that we need to start looking more closely and more frequently at our 60 year old airplanes is totally valid in my opinion. As per the specific thread(s) on the subject my opinion is that there needs to be changes in the AD, but we definitely need to be looking at our structures much more now than we ever did before. "

This has been my point exactly and earlier. The information needs to be put in our hands for us to use wisely for everyone's safety, not rammed down our throats at gun point. Earlier, I called for a comprehensive inspection manual gleaned from information found here and elsewhere, especially from the more experienced and knowledgeable members. A lot of times, we seem to have a 'don't ask don't tell' mentality. If you don't ask, we won't tell.

[Forrest Barber]

Re: Stas

Amen , look them over good! I was a bit concerned that the M&D's
( Malfunction & Defect Reports) were not really used a lot. I have discussed other failures that I am aware of with the FAA engineer . Look for the new thread with the ACS IF I can convert the PDF. bye

[NY86]

Re: Stas

The bottom line seems to be "Fix your wagon before someone else fixes your wagon for you..."

[Skydivematt]

Re: Structural failure statistics

The bottom line is that all of us with freshly rebuilt aircraft are being forced to tear our airplanes apart.

[Ron Coleman]

Re: Structural failure statistics

I'll make you a bet that there will be a lot of damage and stress to fittings and attach points during the act of removing struts to look for damage and stress cracks.

RonC
N96995

[Hank Jarrett]

Re: Structural failure statistics

Pulling your struts may look easy but take it easy when you do. You have TREMENDOUS leverage at the end of those struts and can easly damage them when you lower them (not to mention you have the potential to DROP THE WING or damage teh fuselage fitting!). If you have the SLIGHTEST doubt (and maybe even if you don't) in your ability to safely take your struts off, get some help from someone (like an old time A&P, not one of the Beach Jet crowd). After you have done it once with someone who knows what they are doing it is easy, but it would be a shame to damage a plane or set of struts and then find out the struts were OK. I think we will loose more struts to removal, transportation and install damage than from corrosion.
Hank

[cpirrmann]

Re: Structural failure statistics

That's what I'm wondering about, What if I ship my struts, they get tested OK and then get pretzelled in shipping on the way back? I guess that's what insurance is for.

[Forrest Barber]

Re: Structural failure statistics

Our X-ray procedure yesterday was with the struts in place and went fine.
The AMOC should go thru okay. Struts off, struts on, it is a matter of good workmanship by your A&P or IA. I too agree that shipping can be a problem, anybody need a slightly bent ( curved) American Champion 7KCAB front strut. The handlers on a major air line bent it in the shipping tube to fit into a cargo door!!

[O.Taylor]

Re: Structural failure statistics

I was thinking of this type of discussion the other morning while driving to work at a different airport than I usually work at, thinking of "why do we need an AD if a descent inspection has been done?", I find rusted out tubing every once in awhile, AC43.13-1B has been written to help us FIGURE OUT HOW TO REPAIR IT, when I look up and there on the side of the road is a state sign: "Observe traffic signals", OH, AM I SUPPOSED TO DO THAT???, WHY HASN'T SOMEONE TOLD ME BEFORE NOW. I feel the hand of the government upon me more each day, sadly. Have a Happy Day, O.T.