Pelican’s Perch #20: Ground All Bonanzas?

The crash of a Beech T-34A in simulated air combat at Sky Warriors near Atlanta triggered an investigation involving the NTSB, the FAA, and Raytheon Aircraft Company. AVweb's resident pelican, John Deakin - who is current in T-34s himself - has been looking closely at this investigation, and believes that it is taking a wrong and dangerous direction that could wind up putting a lot of perfectly good airplanes on the ground ... not just T-34s, but also Aerobatic Bonanzas, early-model Bonanzas that use the same wing spar design as the T-34, and might ultimately have implications for all Bonanzas and perhaps even other models as well. John explains why he thinks the NTSB may be on the wrong track in looking for a probable cause, and why other participants in the investigation may have ulterior motives.

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Editor’s Note: Because of ongoing controversy with the Beech T-34 wing spars, John Deakin updated this 1999 column in May 2005. His updates are [bracketed in red], but the entire column is even more relevant today than it was then.


Ground all Bonanzas?Well, no, not immediately, and all parties will deny that this is even a possibility … but I don’t think Bonanza owners should be very comfortable with what’s been happening in the aftermath of last April’s Sky Warriors T-34 crash. I believe there is a strong chance this will eventually have major repercussions in the Bonanza world, if not the entire general aviation fleet.As I discuss the issues involved, please bear with me … it’s complicated. And every time I mention “T-34” below, please substitute in your mind the name of your favorite flying flivver, and imagine a crash where the structure is even slightly suspect. Because I believe that there’s nothing going on in this case that couldn’t apply equally to any other aluminum airplane.

Let me say up front that I’m truly appalled at what’s going on. I have seldom seen so many different owner organizations and alphabet groups so screwed up over a single issue as they are over this one. The NTSB seems to be doing a particularly lousy job on the investigation. Worst of all, the user groups — whose job it is to represent the interests of the owners of these aircraft — seem to be sheep, headed over a cliff of willful ignorance. [May 2005 Update: I blew that one, and I owe the NTSB an apology. The NTSB nailed it, and told the FAA it was the abuse of the T-34 beyond its limits in “Mock Aerial Combat.” The FAA did not respond, acknowledge, or take action.]Why should you care about any of this? True, right now only the T-34s are at risk, but we all need to pay attention — now! I believe that if events run their course in the current direction, it is very possible that most aircraft in “the Bonanza family” may be subject to another FAA-mandated fiasco that makes the V-Tail crisis of the ’80s look tame by comparison. It is possible the entire fleet could be grounded while a “fix” is designed and approved, and that the fix could be so expensive that many Bonanza owners would simply have to junk their airplanes because the fix would be economically disastrous. Others would be burdened with costs in lost time, money, and useful load.At this point, it is all too easy for the alphabet groups and owner associations to sit back and say, “Well, the investigation isn’t complete, and we don’t even know what happened, yet, so let’s wait and see.”True, the investigation is not complete. The NTSB ain’t talking, and the fat lady hasn’t sung. But there are some frightening signs that lead me to believe the investigation is badly off track, and may never get back on. Many of the current participants have “mixed motives” at best, and the key players appear to be rushing ahead with a fix that isn’t.

What Happened?

In recent years, a number of firms have come into existence to allow would-be fighter pilots to engage in mock aerial combat, using a variety of aircraft that give the look and feel of a combat aircraft. Most of these are well-run outfits that put safety first, with extensive training and well-maintained equipment. Most employ only instructors with real military experience at aerial combat, and all require the presence of such an instructor on all flights. Some have sophisticated laser sighting equipment that can register “hits” on the other aircraft, and some “victims” even trail smoke when a hit is detected. All good clean fun. [Update: I wish I hadn’t said that!]Sessions are recorded on videotape, with some simultaneously recording the forward view, the pilot’s face, and perhaps the instrument panel. The intercom is also recorded, so the tape will catch all the g-load grunts and chatter.It’s pretty pricey fun, with the lowest I know of starting around $500 per flight. The nature of the game requires at least two aircraft, and some allow even more.

On April 19, 1999, a T-34A Mentor owned and operated by Sky Warriors Inc. of Atlanta, Ga., was on such a flight with a very high-time retired airline pilot as the customer in the front seat, and the usual instructor in back.To relate to you the events that led up to the in-flight breakup of that aircraft requires me to engage in a certain amount of speculation. The mission was videotaped, but the NTSB has not made the tape or even a transcript available to anyone not directly involved in the investigation. There is some question over the ownership of the videotape (with Sky Warriors and the estate of the deceased customer-pilot both claiming ownership) and questions over privacy issues, with rumors of prior awards for public release of such tapes. For whatever reasons, the NTSB has sequestered the tapes, with only “interested parties” allowed to see them. To date, that includes only the NTSB, the FAA, and possibly Raytheon Aircraft Company (RAC), although some RAC people say RAC has not seen them. Apparently others have looked at some of the aircraft parts, and some pictures of the failure points have been circulated.In any case, I have not seen or heard any tapes or tape transcripts nor inspected parts from the accident aircraft at the time of this writing, and so I must rely on secondhand (or in some cases third-hand) information. With those caveats, let me proceed.The tapes are rumored to reveal that a head-on pass was set up for engagement, with one aircraft at 7,000 feet, and the accident aircraft at 8,000 feet (if memory serves). The pilot of the accident aircraft spotted the “enemy” below, and began an aggressive diving turn to begin the “fight.” From various clues, it is fairly obvious that the dive speed approached the redline, and perhaps even exceeded it — not an unknown condition in the heat of battle. The audio is rumored to have recorded something to the effect of the instructor calling “going through 4g, now 5g,” after which a roll to the left was reportedly seen on the video.At that point, the right wing failed, but remained somewhat attached to the aircraft, perhaps by the aileron cables. Accounts differ, but the flailing wing apparently banged into the cockpit area one or more times on the way down, and in so doing may have killed or injured one or both occupants, preventing their egress. (There are no ejection seats in the T-34.) Neither occupant got out as the aircraft descended rapidly to the ground, and both pilots were killed.Just two weeks prior to the Sky Warriors breakup, there was another disturbingly similar accident. From RAC’s Safety Communique No. 162, dated May 1999:

“On April 5, 1999, another Beech T-34A crashed at Maracay, Venezuela, as a result of an in-flight wing separation following the performance of aerobatic maneuvers. An investigation was conducted by Venezuelan authorities, with the assistance from RAC. The separation surfaces in the Venezuelan crash have not been available for inspection by RAC metallurgists and we are not certain whether those surfaces would also reflect the presence of fatigue.”

[Update: From the best available information, the Venezuela crash was pure overload, with no known evidence of pre-existing fatigue.]In addition to these two, there is one other long-ago T-34 in-flight breakup on record, but otherwise this neat little aircraft enjoys a wonderful safety record, with many enthusiastic owners. The safety record of the “mock combat” outfits has also been exemplary. [Update: This seemed to be true in 1999, but later events have turned up other problems not then apparent.] That’s even more impressive when you consider the use and abuse to which these aircraft are often put.The accident aircraft (and many similar ones) had about 4,000 “sorties,” or flights in which high-energy, high-g loads were repeatedly imposed. There is no way of measuring how many such events took place on the average flight, but it’s fair to assume “many,” given the nature of the program. I’ve also heard reports that the majority do a few yo-yos, get nauseated, and go home, cutting the session short. In any event, these are some pretty seriously abused airplanes, and they’ve held up very, very well.

Rush to Judgment?

A visual inspection of the wing separation points reportedly reveals some fatigue cracking, with similar cracks apparently found in the other wing. It seems everyone promptly decided this was the only cause of the accident, and the entire course of subsequent events has been based on this scenario.Repeating, the unofficial (RAC/FAA/NTSB) party line seems to be that the wing had fatigue cracks, and these cracks caused the wing to fail under high g-loading.While this simplistic explanation may be an appropriate hypothesis for one line of investigation, I consider it criminal for the investigators to proceed under such an assumption without looking for other possibilities. There are other possibilities, and (in my opinion) far more likely ones! One of the most fundamental rules of accident investigation is this: Never become committed to any one explanation for an accident until all reasonable alternative explanations have been identified and examined. It is my clear impression that the folks investigating the Sky Warriors accident have failed to follow this basic rule.It also appears that no one involved in the investigation has asked, or is now asking, what I consider to be the most salient question of all: What was the initial point of failure? What broke first?The “fact” that the front spar has fatigue cracks, and that it failed, does not mean it failed first! Lots of airplanes have fatigue cracks. In fact, if you look closely enough with a strong enough magnifier, virtually all aluminum airplanes eventually develop fatigue cracks! But that doesn’t mean that they’re unsafe. Primary aircraft structures are “overbuilt” and built with “fail-safe” design to compensate for the fact that no older aircraft has the same structural characteristics as it did when it first rolled off the assembly line.Yes, the airplane broke up and crashed. Yes, fatigue cracks were found in the front wing spar. But no, this doesn’t necessarily mean that the fatigue cracks were the primary culprit in the crash. Yet the investigators seem to be leaping to this conclusion without looking for other possible causes.As a result of this badly flawed assumption, there has been a rush to judgment and a knee-jerk reaction that may forever ground the T-34 fleet. If this same sort of thinking (or lack thereof) is used in the future, other major portions of the GA fleet could be treated the same way. This is a bad precedent that could ultimately affect all of us if not nipped in the bud now.Very quickly after the accident, RAC (who absorbed Beech) stated in the strongest possible words that no T-34 should fly until the investigation is complete. Mercifully, this strong statement is not legally binding, and very few T-34 owners paid much attention. The FAA, acting in a wiser and more rational fashion, simply slapped some restrictions on the airplane — a speed limit of 152 knots, and a maximum g-loading of 2.5g — which at least permitted the fleet to continue flying. Good move, FAA! I have no criticism of this as a temporary measure, although it probably should have been lifted [Update: for aircraft not used in mock aerial combat] rather quickly once the initial facts came out.[Update: But the abusive use of T-34s in mock combat continued. In November 2003, a nearly identical inflight breakup occurred. This aircraft was scheduled for one of the then-available kits as an “Alternative Means of Compliance,” but it had not been properly inspected, and apparently was flying outside the flight restrictions imposed on non-modified aircraft (speed limit, 2.5g, and no acro).Key point: All T-34s used in mock combat show fatigue damage, with three inflight failures. To date, only one T-34 not used in mock combat has been found to have fatigue damage, and that was an aircraft with documented, heavy-duty, long-term aerobatics.The fleet is now being inspected by a newly-developed eddy current inspection, and this additional data should help to develop good fixes. Ive personally seen this inspection, and its incredible stuff. Very accurate, and very easy to do.]From where I sit, it looks as if 100% of all current attention is now focussed on a “fix” for the presumed spar crack problem, with a final proposal due to come from RAC at any moment. According to RAC, the FAA has said it will move quickly, perhaps within a few weeks, to make this a mandatory AD. This before the NTSB has even announced a “probable cause”!

RAC’s “Fix”

The anticipated Draconian action will require the removal and subsequent reinstallation of the fuel bladders, no trivial task itself. A number of rivets in the primary structure of the lower wing surface at the front spar will be removed and replaced by bolts. Since those bolts need something to screw into, special nutplates will be installed inside the fuel tank cavity, inside a critically narrow channel on the bottom forward side of the front spar. Beech maintenance gurus tell me that this very painstaking process may require an A&P who is also a dentist experienced in root canal surgery. Drilling the rivets out and reaming the holes just slightly oversize is apparently a very critical process, and I’m told that any slip or error will destroy the wing permanently. If I were an A&P, I wouldn’t try this even on my own airplane — I’d rather be able to sue someone else.While the new bolt holes are vacant, they will be tested for flaws by the “eddy current” process. According to non-destructive testing (NDT) experts I’ve talked to, this is a highly subjective test with results very uncertain. In case you’ve never seen it done, eddy current testing involves an expert NDT technician watching an oscilloscope trace as a probe is moved across the part to be tested, and trying to interpret squiggles in that trace. I’ve heard that one part (not from the crashed aircraft) was tested twice. Reportedly, it passed the first time, and failed the second, with nothing else done in between the two tests! There is no reason to believe any spar (including a brand new one) will have any guarantee of passing this test. The NDT gurus say that eddy current testing is useful in detecting flaws in solid metal components, but far less effective in testing multiple layers of different metals such as the T-34 spar. In any case, two experts are likely to see two different outcomes from the same test.If the spar passes the eddy current test, the bolts will be screwed back in, and the airplane returned to service — only to be subjected to the same test again every 50 hours thereafter! RAC mumbles something to the effect that if repetitive tests reveal no general problem with the fleet, the 50-hour requirement “may” be modified – “someday.” I’m not holding my breath.Time estimates alone for the initial “fix” range from a minimum of 50 hours of labor, to well over 100 hours. Eddy current testing is available at only a few locations around the country, with very few well-qualified people to do it.This is RACs definitive answer to the T-34 problem … their ONLY answer! Several user groups seem to be shrugging their collective shoulders, and saying, in effect, “Hey, it’s a fix, and it’ll get us back in the air, so let’s support it!” But it looks to me as if they’re lambs being led to slaughter, and just don’t know it yet.[Update: Eddy current testing in 2005 is quite effective, if done properly. The folks at GAMI (General Aviation Modifications, Inc., of Ada, Okla.) have now identified the specific area, and can identify fatigue cracks with great precision. They have a process that fixes the cracks, and a most elegant, highly engineered add-on plate (internal) that totally and permanently fixes the problem.]

A Short Course in G-Loading

Do I know what happened, or what the fix should be? Of course not. But the available evidence suggests a far more likely scenario, and one that I believe deserves some real investigation. Follow me through here.All pilots — especially pilots who engage in aerobatics — should understand g-loading thoroughly. Unfortunately, many pilots don’t learn any more than necessary to get past the FAA knowledge tests, after which they forget it forever. That’s too bad, because this is a very important subject.The FARs require “Normal” category aircraft to be able to withstand at least 3.8g positive flight loads. “Utility” category must withstand 4.4g, and “Acrobatic” category aircraft 6.0g.[Update: Most Bonanzas are in the Utility category, but the T-34 is in the Acrobatic category. Both have essentially the same wing and center-section carry-through structure. The Bonanzas are much heavier than the T-34; so in the end, the actual stress on the wings and center sections are about the same at 4.4g in the Bonanza and 6.0g in the T-34.]Also, all GA aircraft have a “Maneuvering Speed” (Va) published in the “Limitations” section of the POH. If you are flying at or below that speed, you can move any flight control to its full limits, without damaging the airplane. Many pilots do understand that full “nose up” elevator deflection at exactly Va will result in the aircraft stalling just as it reaches the design limit load factor. That relieves the wings of any greater stress. To put it another way, if you’re pulling more than 6g in the T-34, you’re going too fast! As the speed is increased above Va, it becomes possible to pull much higher g-loads than the airframe was designed to take, obviously overstressing the wings, and it won’t take full nose up elevator to do it, either.[Update: Fatigue is cumulative. That is, you can badly overstress an airframe once with no measurable damage. 100 times, perhaps. But every time there is a “strain,” there is some fatigue, and it adds up. Hundreds or a thousand 6.0g loadings are extremely destructive to a 6.0g airframe! We now know that the only T-34s that have measurable fatigue are those few aircraft used in “mock air combat,” for thousands of hours, with frequent overloads. It is common for those instructors to yell, “Pull, pull, pull to the buffet!” at high speed. Even if the g-meter only reads 6.0g, the instantaneous g-loads at each buffet cycle can go much higher, and the “count” adds up quickly.]The Sky Warriors T-34 was probably going faster than 200 knots (Vne is 214) and clearly far above Va (148 knots in the T-34). It was therefore capable of being destructively overstressed by an unwary pilot. At 200 knots, more than 9g can be imposed before the wing will stall.Most pilots are at least exposed to the above principles with reference to pitch forces. In all cases I know of, they are shown the “symmetric loading” case, where there are no roll or yaw forces present, only pitch forces.[Update: I originally questioned the issue of whether these “missions” were really pulling more than 6.0g. I don’t like anything over about 4.5g myself, these days; but I’m overweight, 65 years old, with very low blood pressure. I can remember pulling 6.0 in aircraft intended for that use (Pitts Special, others), and I didn’t like more than 6.0g about the same as I don’t like more than 4.0 today. But accurate, sensitive g-meters will show momentary or instantaneous loads far above what the pilot perceives, and without knocking him out.]The FARs also address the certification standards for rolling the aircraft, and Va gives full protection for stresses on the wing at Va with full aileron deflection.But not at 6g in pitch!Read that again, please, it’s critical to what follows.In other words, you may pull full back at Va, or you can apply full aileron at Va, but you can’t do both at once!Any combined pitch and roll loads are called “asymmetric wing loading,” and are of major importance. For example, modern military jet fighters routinely fly at well over 7g, and some even exceed 9g . ALL have major restrictions on how much g-load can be pulled while rolling. I am told the F-15 must be “unloaded” (in pitch) to under 2.5g, if full roll rate is needed. A key point in Air Combat Maneuvering (ACM) is to “unload,” “reposition the lift vector” (by rolling), then “load,” again. For example, if coming down the backside of a loop, pulling 7g, and you suddenly look out to your left and realize you need to go that way “right now,” you must first “unload” to under 2.5g, then roll (pointing the lift vector), then “pull” to go that way. Watch any of the high-performance jets at airshows — this is very clear, if you know what you’re looking for.In the F-15, any attempt to pull more than 2.5g in pitch and use full aileron deflection at the same time will probably destroy the airplane, because this is outside the operating envelope. An entire F-16 squadron in Europe was trashed because the pilots were either unaware of this limit, or routinely pushed it just a little too much, and caused too much fatigue over time.(Now folks, I’m T-34 qualified, but not F-15 qualified, and so I may have some of those specific numbers a little bit wrong. Give me a little room for error there, and try to understand the principle, which I do not have wrong.)[Update: No one has stepped forward to contradict that statement in six years.](During EAA AirVenture, in a room with about 150 T-34 pilots, I asked, “Show of hands: How many in this room have heard the term ‘asymmetric wing loading’ and think they understand it?” A lot of hands went up, but a lot more didn’t — and some that did appeared to be none too certain.)Back to the Sky Warriors breakup. There was an experienced pilot in front, so the instructor might have been just a wee bit more relaxed than usual in his oversight, and may not have been ready to block the controls from a dangerous input. The customer almost certainly did not understand asymmetric wing loading (there’s not much call for that in airline flying), and it’s just possible the instructor did not fully understand it, either.[Update: It is very, very difficult for even a good instructor to “block” another pilot from pulling hard, then applying roll input.]They spot the target below, and dive and turn to engage, possibly exceeding 200 knots, maybe even a lot faster — very easy to do in the T-34. The g-load builds to “four, going to five,” and then the tape reportedly shows an increased roll rate to the left.That’s an absolutely classic setup for “asymmetrical wing loading,” and the numbers are terrifying. It’s very possible they were beyond the limits for the “simple” (no roll) case of 6g, plus they were rolling, too!What does this do to the airplane? Since the roll is to the left, the right wing is forced to suddenly produce “more lift” by the aileron deflected downwards. That moves the leverage at the wing root well outboard, and well aft, producing a major twisting force on the wing, loading the rear spar far beyond design limits.If that happened, the rear spar would fail, and the wing would twist off and fold. The front spar would inevitably fail, of course, with or without fatigue cracks.And you’d have precisely the accident we’re looking at.If this is the correct explanation, then the proper action is … nothing! If I’m correct, the airplane was grossly overstressed far beyond its limits, and simple pilot education is all that is needed. Just like the F-15, “Don’t pull hard, and roll hard, simultaneously.”

What Axe Is RAC Grinding?

Now, if a dummy like me can figure this out (with a little help from my friends), RAC surely can. Why wouldn’t they? Why didn’t they?It is just possible there is an agenda here, and an ugly one.Let’s face it: Raytheon is fundamentally uninterested in piston airplanes to begin with. Folks, wake up, please? It’s no longer “Beech” or “Beechcraft.” Walter and Olive Ann are long gone, and there isn’t any romance with aviation left. Like all big companies, Raytheon’s only consideration is the bottom line in the next quarterly report. The thought of having anything to do with 50-year-old airplanes must give them nightmares in the Raytheon boardroom. The GARA 18-year “Statute of Repose” has cleared them of all liability on the T-34, and they have nothing to gain by getting involved, risking any new liability. Fact is, Raytheon has never supported the civilian T-34 in any way.But there is some pressure from the FAA for RAC to help out with the situation, and Raytheon certainly wants to keep the FAA happy. So what better steps could the company take than come up with this madness of an eddy current inspection, which may very well ground all or most of the T-34 fleet? RAC can act all sympathetic in public. They can send “reps” to address the user groups, as they did in Fond du Lac during Oshkosh — where they sent a marketing rep, not a tech rep! They can offer drawings and other support without incurring liability. But the moment they put a new part on an old airplane, they open the Pandora’s box of liability. If I were running RAC, I wouldn’t do it either.RAC has stated repeatedly that it will provide zero financial assistance, and I agree they should have no obligation in this matter. No criticism on that, from me. RAC has stated in public that they have spent a good deal of time, effort, and money on this T-34 “problem,” and I believe it. If nothing else, every move they make has to be carefully scrutinized by their legal eagles, to make sure they are not opening that box, and so RAC’s legal fees must be substantial. Legal costs aside, it takes attention, man-hours, meetings and other expensive resources.Several folks have told me that RAC reps have said RAC would be delighted if the entire T-34 fleet was just grounded forever. I believe that, too. While I haven’t heard anyone from RAC say this with my own ears, it makes sense from an economic point of view. Remember, at giant Raytheon, economics is the only point of view.The eddy current inspection is so stupid — and the rush to judgment is so obvious — that I can only wonder if RAC has come up with a very clever ploy to accomplish several desirable (for RAC) things at once. They come up with a fix that requires nothing from RAC except written instructions. (38 pages, according to one RAC rep, and it’s not finished yet.) RAC gets to wear the white hat for being “helpful.” But the eddy current test may well ground the fleet, at which point RAC gets to wash its hands of the whole matter.[Update: I wish I’d said that differently. My objection was not over the eddy-current process itself, but over the massive disassembly required to do it the RAC way, and the 50-hour limit, when it had to be done all over again!]What’s next under the eddy current microscope? All the acrobatic Bonanzas? All the early V-Tails that use the same spar as the T-34? All Bonanzas? How about Barons? Once the crack detectors are set loose, is any aluminum airplane safe?

0)]RAC has done some puzzling things during the course of this mess. Julie Clark, the airshow performer who uses a T-34, voluntarily stopped doing her shows, and has lost a ton of revenue as a result. In an effort to be helpful and move the investigation along, she voluntarily gave one of her T-34’s wings up to RAC for examination. This was priceless evidence, for Julie has operated the aircraft to highly precise limits, for a very long time, with immaculate records, and has been its only owner for many, many years. This wing could have been tested, first by non-destructive means, then (if warranted) by testing to destruction, and close examination.But before anything substantive was done, the wing was cut in half (without Julie’s permission!) to “make it easier to transport” to RAC. This was a criminal act, in my opinion. Julie is the only T-34 owner who has been totally grounded, since her airplane doesn’t fly well with just one wing.

How About the FAA?

The FAA is short-staffed, short of money, and unwilling to do anything it doesn’t absolutely have to do. [Update: Remember, this was originally written in the summer of 1999. This situation has gotten much worse since then.] In fact, it’s getting damned difficult to get the FAA to do things that it is supposed to do! Functions previously reserved only to the FAA are being farmed out to outside agencies, taking them out of the FAA budget. In effect, user fees by another name.Many of the best FAA people have bailed out for jobs in the private sector, leaving a higher percentage of drones than before. Yes, there are still some very good people, laboring under very tiresome situations. It must be very hard to keep up any kind of morale.For the FAA in general, there is nothing to be gained by getting involved in airworthiness issues on a 50-year-old airplane like the T-34. All indications are that if RAC comes up with anything that “sounds good,” the FAA will rubber-stamp it and send it out the door as a mandatory AD, washing its hands of the whole matter.[Update: With that, the precedent would have been set. We know there are a number of Bonanzas “out there” that have suffered massive overloads, but were repaired without inspecting the area most likely to have suffered the most fatigue damage. Let just one of these aircraft “fall out of the sky” for any reason, and if there is damage there, we may see 10,000 Bonanzas treated exactly like the T-34.]

Finally, the NTSB

In my opinion, the National Transportation Safety Board (NTSB) has gone downhill steadily since the advent of Cockpit Voice Recorders and Flight Data Recorders (CVRs and FDRs), which have all but replaced good hard detective work in crash investigation, instead of supplementing it. The agency has become increasingly political, with fewer and fewer qualified people. The top jobs go to political appointees regardless of talent or qualifications, although a good TV image is very important. They are forced to react to the media and public pressure, always with demands for instant results. Other agencies often interfere (witness the FBI screwup in the TWA 800 investigation).I can recall some outstanding forensic work decades ago by the true experts. For example, the Trans International DC-8 crash at JFK, and the rudder hinge failure on the 707 doing a low circling approach in training with two engines pulled back on the same side. Those accident reports were works of art, compared to some of the trash turned out by the NTSB today. Experts like that seem to be few and far between, now. Like the FAA, NTSB resources are short, and there is no time or money to do really good work. Again, why should the board bother much with a 50-year-old “toy” airplane (no disrespect intended, I like the T-34), when they don’t even have the time or resources to solve the TWA 800 case, or the two yet-unexplained Boeing 737 crashes? Once investigators discovered fatigue cracks in the T-34 front wing spar, it must have been very, very easy to just relax, and go with that. All indications are that’s just what the NTSB team is in the process of doing, although their report is not yet final.What is most likely to happen is that the NTSB will move glacially, then state the probable cause as wing failure due to pre-existing fatigue. Case closed, and it will be all but impossible to reopen it at that point.[Update: OK, time to eat some more crow here (pass the salt). They really did nail the issue after the first crash in 1999 (after I wrote the column). They made it crystal clear that the real problem was the extremely abusive and inappropriate use of a fine aircraft. To this day, the FAA has failed to come to grips with the concept that there are two different fleets, with two very different fatigue patterns.]

What Can Be Done?

The best and most obvious course of action is for the user groups to get together and hire a very highly regarded outside expert, and have that person gain “Interested Party” status with the NTSB. This will allow firsthand examination of all the evidence now in existence by an unbiased third party with no axe to grind. If this expert feels it is warranted, further action could be taken as needed, whether that includes the RAC fix, or some other course of action.Please note this is in no way a suggestion to alter the course of the current NTSB/FAA/RAC investigation, or to slow it down, or complicate it. This is a suggestion for a parallel investigation, by an outside party. All information should be shared fully, even if only one way (to the NTSB). We should not be trying to play one-upsmanship games here, we should be looking for the truth as it is, not as we would like it to be, and for a genuine solution, if there is a real problem.If all parties are currently proceeding in an intellectually honest manner (and that’s a very big “if”), they will welcome this as an added search for the truth. If they do not welcome this parallel investigation, that would indicate all the more need for it. This is exactly comparable to getting bad news from a doctor, and saying that you might like a second opinion. If the doctor blows up and yells at you, it’s pretty good evidence that second opinion is a really, really good idea. The good doctors will suggest the second (and even third) opinion, and mean it.There is a splinter movement from the T-34 group afoot, and the American Bonanza Society (ABS) seems to be waking up and deciding that it might be a good idea for them to get just a wee bit more involved. That’s good news. [Update: They didn’t, sadly.]The bad news? It’s going to take money, and the ABS may not be willing to foot the bill. I’m a member, and they’ve hereby got my vote to proceed with all speed to make sure that all reasonable avenues are explored by someone who knows how to do it. But if this job is to be done right, and it must be, then it’s going to take $15,000 to $30,000 for a good expert to do it. Spread among the T-34 owners, that’s trivial, and if the ABS will come in with help, the burden will be small indeed, at the individual level.The T-34 splinter group has already gained pledges of over $9,000 in just 24 hours, and will be sending information to all the members soon.Remember, there is no one interested in keeping these birds flying — except you.[Update: George Braly and Tim Roehl of GAMI were deeply involved from the start; and after some bickering and politics by various groups, “The T-34 Spar Corp.” was formed. Contributions were accepted from the T-34 users to fund a huge engineering effort by George, resulting in a most elegant and economical AMOC (Alternative Means of Compliance) for the problem. Both are very quick to “fade into the background,” and give a lot of credit to others, but I believe they personally funded a large portion of the effort, and I have personally witnessed a massive expenditure of effort and time by George himself. They are very reticent on this issue. Those who did contribute to the effort received discounts on the repair.George also insists on giving a lot of credit to others who developed other AMOCs. He lists Nogle and Black for getting approval to replace the T-34 spar with a Baron spar, and Earle Parks for a different spar modification: A spar strap was developed.The most recent crash in Texas was very different, a whole new problem, although still a fatigue issue. This time there is much more cooperation, with Nogle and Black helping GAMI, and many people contributing time, effort and money to another massive engineering effort.If this group is successful, they may set the new “Gold Standard” on how to deal with this type of problem in the future. It would be very helpful if the FAA could find a way to be much more flexible in how they deal with these problems. If they dont, these “orphaned” aircraft may end up grounded, and the FAA will be out of a job.]Be careful up there!


AVweb’s resident pelican, John Deakin, has dozens of other columns available.


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