NTSB Report On Tennessee V-35 Could Include A First

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The National Transportation Safety Board (NTSB) has issued its preliminary report on the May 15 fatal in-flight-breakup accident involving Bonanza N47WT near Nashville, Tennessee. It answers some, but not all, of the questions on how this accident happened. One segment of the report suggests that the accident could mark the first time, ever, that a Bonanza top wing bolt has fractured.

The report shows that the pilot, Dr. Lucius Doucet III of Louisiana, purchased the 1966 V35 Bonanza in December last year, registering it in January. Though it does not detail how long he had his pilot’s license or what ratings he held, his total logged flight time was 366 hours, with 15 hours in type. What is also still not clear is the extent of his instrument flying experience, nor what training he might have received specific to the V-tail Bonanza.

The report newly reveals that about three hours after departing from Louisiana at 8:50 a.m. CDT on May 15, Dr. Doucet was in contact with Memphis Center on a northeasterly heading at 7,000 feet toward his destination of Louisville, Kentucky. He requested a “deviation” and a climb to 9,000 feet as he approached Nashville Approach’s airspace. There were areas of precipitation in the area, though convective activity was characterized as “light.” Memphis Center relayed the request to the Nashville Approach controller, though no reason was given by the pilot for the request. After the switch to Nashville Approach control, the pilot was given a vector of 360 degrees and was advised to expect a turn back on course in about 15 miles.

The vector took him into an area of medium to heavy precipitation. He climbed to close to 10,000 feet and was instructed twice to maintain 9,000, which he acknowledged with “descending to 9,000.” Once cleared to turn back on course, his heading began to fluctuate, and he no longer responded to radio calls. After flying “several miles” toward the assigned VOR, the Bonanza began a tight right turn to 213 degrees and its rate of descent began to increase, ultimately reaching as high as 15,000 feet per minute.

Another new piece of information in the NTSB report is that a witness recorded video of parts of the airplane emerging from the base of clouds, indicating that the breakup occurred before the Bonanza descended into clear air.

AVweb asked Tom Turner, executive director of the American Bonanza Society, for comment, and he responded: “The NTSB preliminary report describes an accident sequence beginning with departure from controlled flight for unknown reasons that led to a steep spiral dive from which the pilot does not recover. This in turn leads to exceeding Vne and stressing the airframe beyond design limits, resulting in an inflight breakup.

“The only anomaly in this report is that it appears the left wing’s top, forward wing bolt ‘fractured.’ If true, this is the first documented case of wing bolt failure in flight in a Bonanza. It may be the fitting failed and the bolt remained intact, and the NTSB was not clear in its preliminary report. But the description of damage to the other wing attach points is different. So, if in fact, the bolt itself failed this may be a bellwether.”

Mark Phelps
Mark Phelps is a senior editor at AVweb. He is an instrument rated private pilot and former owner of a Grumman American AA1B and a V-tail Bonanza.

40 COMMENTS

  1. So, a Doctor was flying a Bonanza and there was an in-flight breakup? Hardly a “1st”.

    • We need a special Comments section for those who comment on the headline rather than reading the article.

    • The headline says the REPORT, may contain a first, and then goes on to describe the breaking of a bolt in this incident as the first, Not that a v-tail crashed, or that a doctor was flying it. Do you always look at life through brown tinted glasses?

  2. The spatial disorientation of the pilot occurred first, most likely precipitating the loss of control and resulting in a steep spiral dive. This uncontrolled descent led to the aircraft exceeding its structural limits, causing the in-flight breakup of the aircraft-period.

    • I’m curious about the potential in-flight effects of a “fracture” of the top forward spar attach bolt. Could such a fracture allow a subtle alteration of that wing’s angle of attack, leading to progressive control difficulties especially in IMC? What was the status of the other attach bolt(s)? Would one fail but the other(s) still be sufficient to secure the wing’s AOA? I don’t have any knowledge of the details of the spar attachment.

  3. Raf is correct Jethro. The positive G limits are 4.4, the ultimate (structural tested limit) is 6.6.
    Anything above that number could lead to structural failure and “in flight breakup”….
    Without on board recording (Garmin data?) the G forces are unknown…however, if the wings detach in flight then it is above approximately 8 g’s.
    Misnomer: V tailed doctor killers….better: Doctor’s killing V tails.
    Long time CFII/CFI/MEI with ABS BPPP and now BPt, INc, Navy Test Pilot
    Lottery number: 22 41 54 64 66…PB 01

    • Ha ha! Indeed, many fine airplanes have been killed by inexperienced pilots or stupid mistakes.

  4. Is it normal practice for an NTSB report to not include how long he had his pilot’s license or what ratings he held?

  5. Normal part of the PRELIMINARY Report by the NTSB as their investigation ramps up with a final report issued way down the line– 18 months or more into the future — to not include the full data of pilot certification, ratings,etc when they are still not verified and still must be delved into by way of logbooks , instructor interviews, training center(s),etc.

  6. Didn’t the older vee tails have an identified weak spot in their forward attach fitting? If that failed at high speed and G, the wings would instantly be subjected to negative G failure loads and the top bolts or their fittings would be the logical initial wing failure point. Aluminum + magnesium + steel + time (+ perhaps an AD or two poorly, or not complied with) seems a likely formula for a scenario like this. Just sayin’.

  7. None of the above excuses the pilot. Instrument proficiency is the ultimate responsibility. I’ve signed logbooks “Instrument proficiency check INCOMPLETE” when I wasn’t comfortable with the pilot’s performance. It’s a perishable skill and needs constant nourishment. Hard for some type “A” personalities to accept.

  8. Long ago, I read a report on the Bonanza praising its aerodynamic cleanliness. I can’t remember the numbers, but just a fairly shallow nose down pitch will take it past redline in an astoundingly short time. It was making reference to a pilot’s distraction and how quickly they could pull the plane apart.

    • I don’t have any V35 time in my log book, but I do have about 1000 hours of part 135 flying in an A36 to go next to my other 28,000 hours mostly in jets. I can tell you this, when I was flying the A36 I had maybe 2500 hours and I thought it was one of the nicest and easiest flying airplanes I had flown. That being said I have always told new aviators they must understand that every pilot and every plane has its limitations that must be respected. Unfortunately those professionals such as MDs, lawyers who might in their own right be very good at their profession and very smart have allowed their wallets to kill them. Wisdom is a very valuable asset and I think many of those professional types and otherwise wealthy types forget that when they purchase a high performance aircraft.

    • Guess you missed the main gist of the article, that was that there had never been a report of this particular bolt breaking before this accident.

  9. These comments about Dr killers are tripe; it’s a case of a pilot’s wallet exceeding his skill level. 366hrs total time. What had he flown before? Any dual on type? Any IF training on type (single pilot, new panel, heads down looking for the right switch/system).

    I concur with the comment re IF skills. He’s flying a relatively high performance single, new to him, in convective weather without radar. The initial change in altitude followed by a rapid turn developing into a spiral is classic disorientation.

    • Well, my doctor was killed flying his V-Tail many years ago. These were sold to the public as fast personal planes for professionals and, as it happened, many of whom were doctors. No one back in the day cared about anything but having a license when buying these things. The FAA did not even exist when the first of these planes were flying. I know it’s hard to fathom in today’s world of regulations but the name stuck for a reason back then.

      Only parallel to living in those free and happy days now is getting a motorcycle license in 2 days and being able to buy a 200hp sports bike for the street. Risks? Yea, but it’s all up to you. Don’t be stoopid and freedom is a wonderful thing.

      • My motorcycle qualifications test consisted of riding around the local NG Armory while a DMV dude yelled out commands to do a circle, figure 8, etc.
        Sometime later I took a friend to the new DMV course, which looked mostly like the layout of narrowish hallways in a building. At the end was an accelerate/stop section where you had to get the radar to a certain speed and stop before the line.
        That was it…
        After that, it was the “Good judgement comes with expierence; experience comes from bad judgement” phase.

  10. If the flight track depicted is correct he was vectored and flew into the heaviest precipitation / convention.

    If a controller gives you instructions that you feel are unsafe you may deny them, just say unable, tell the controller why, and do what you have to. Turn around, descend, climb, whatever it takes to keep you alive.

    Complying with ATC is secondary to living to fly another day.

    • True, but that voice on the radio carries an implied air of authority that most new(ish) pilots are reluctant to question. Saying “unable” when you are up to your a$$ in alligators is very difficult when you are thinking (hoping) that they are trying to help you.

      • New pilots could learn that lesson from this accident. Don’t blindly follow everything ATC tells you.

  11. Most likely the accident was due to pilot error, but not a bad reminder to inspect wing bolts for corrosion and to make sure drain holes a not plugged.

  12. Convective activity was “light” but he was vectored into an area of moderate to heavy precipitation? I believe this flight was at night, it appears that he was imc and I’m guessing he didn’t have onboard radar. ATC didn’t do him any favors with that heading.

  13. If the NTSB is thinking that the bolt may have failed, I presume they have at least part of the bolt that can be subject to metallurgical analysis. That would be critical to determine if the bolt had corrosion or a preexisting issue rather than a sudden structural overload. A preexisting condition would most certainly result in an AD for inspection of the fleet.

    On another note, those of you who fly for a living have a different perspective on proficiency than those of us who fly for pleasure, separate from our main avocation. We ALL know and agree that proficiency and thorough knowledge of the plane we fly is important. But those of you who have to demonstrate that proficiency on a routine basis are naturally attuned to keeping those skills fresh. A busy professional who is practicing his/her talents in their own chosen field are current with those skills, but find it difficult to stay current in flying at the same time. I’m not a doctor, but I put myself in that second category. It takes a special effort to overcome your ego that you are good at both things and admit that your flying skills are perishable and need to be honed on a regular basis. Flying a high-performance aircraft makes it even more critical to be proficient and current. I’m not making excuses; I’m encouraging my fellow professionals to recognize just how important it is to know your limits.

    • John, thank you for your very cogent comments.

      I am a doctor, am 80 yrs old, and have been actively flying for 61 years. I’ve owned and flown a C172, a Beech Debonaire, two Cessna 310’s, a P-Baron, a V35, a C337, a C414, a Piper Lance, and now a Comanche 250. I’ve had three engine failures (all in twins) but I’ve never had an accident or incident or FAA violation, in part because I’ve recognized that flying skills are perishable and have attempted to keep current and proficient. Also in part, of course, because of luck, (and maybe in part because I know what an ASRS report is!)

      I know of no data that proves doctors are more likely to die in a Bonanza or any other high performance single than other type-A non-professional pilots, but for some reason the media always seems to be impressed when a doctor screws up. Admittedly doctors tend to be in a higher economic strata than some, and thus may more easily afford a high performance aircraft. So their risk exposure may be higher, but when compared to the well-to-do businessperson or entrepreneur, I doubt there’s much difference.

      • Agree. The idea that doctor-pilots are inherently reckless is simply untrue. In my experience training pilots from a wide range of backgrounds – doctors, law enforcement, educators, skilled laborers, and construction professionals – I’ve found that success hinges on individual aptitude, not their previous profession.

        While doctors’ strong academic foundation often leads them to excel in the theoretical aspects of flying, piloting skills require practice and development for everyone, regardless of background. Some individuals naturally take to flying more readily than others.

      • WBJohn, that’s an impressive list of aircraft! I would be interested in hearing which is your favorite. You make an excellent point about the moniker of “Doctor killer”, when the reality is that anyone who aspires to fly high performance aircraft needs to devote the time and effort to stay current. Busy professional people with a career other than flying have to maintain both their own professional licensing requirements and to be proficient in their flying skills. Since your main profession pays the bills, it obviously takes precedence, but both take time and effort. You can kill yourself in any airplane, but those like a Bonanza require a higher level of skill and experience to operate safely. I have personally had two engine failures, one in a twin and one in a single. They taught me valuable lessons on proficiency and inspecting and maintaining your plane. To paraphrase Mr. Spock, Live long and fly well, sir. 😉

  14. Most airplanes with conventional tail location have a significant download on the tail. Remove the tail and there will be a substantial negative load on the wings.
    The accident airplane right stabilizer with more than half of the ruddervator attached, as well as the left ruddervator were the first parts in the breakup path. The failure of the left upper main spar bolt along with both rear spar bolts is to be expected with the severe negative G that followed the tail failure. As a side note this is not the first failure of a Bonanza upper wing bolt.
    I remember a very early Bonanza accident where one wing came down in deep snow with only minor damage. A A&P/AI friend who recovered the wreckage said the one wing was in near perfect condition. The Beech wing bolts are a flawed design that continued thru the Travel Air, Baron, Queen Air and many early King Airs.

    • I agree with your negative G theory. But the “very early” Bonanza’s were quite different from the later. I’ve picked up bonanza’s where the wing was completely severed at the root and those bolts didn’t shown any signs of distress. This was a Bonanza incident where the pilot forgot to remove his locking gust lock before takeoff and ran it into a tree. I have no Idea if he was a doctor. I too recovered and also rebuilt numerous Bonanzas and Barons with well over twenty years doing so and I’ve never heard of the wing attachement being a “flawed” design. That same design is continued through models delivered to this day. As few as there may be. You might want to post your sources for this new information.

  15. The problem here is the upper wing attachment in a positive G situation is in compression. Bolts don’t fail in compression nor would the attach bathtub fittings. Having removed and installed virtually hundreds of these bolts, I would be totally amazed to hear that bolt itself failed. Much more likely the attachment structure itself if anything did. If it or any of the components of the upper wing attachment fails, it would have to be in a negative G situation not positive. And believe me, from experience that is totally possible in thunderstorm conditions.

    From what I have read so far, it would seem very plausible the good doctor was already in heavy turbulence when he requested the change in altitude and heading. More than likely following what he interpreted from his avionics. And it also appears the controller wasn’t a whole lot of help to him. I had mentioned on another post where a controller vectored us into an area of heavy storm (in an A36 I might add with only a Stormscope to help) for what was said to be traffic issues in the Tampa area. We entered that weather, got beat all to hell and when we cleared out of it, we were well over a thousand feet higher than our assigned altitude.

    For all of those trashing the good Doctor I would hold off until the facts are in. Until you’ve been there you have no idea what mother nature can put you through. And as for all the speak about Vne? You do not need forward airspeed to tear an aircraft apart in these conditions. He could have very easily penetrated tornadic weather for all we know. Tossed around like a feather.

    And finally, just when did the American Bonanza Society become the go to experts on these matters? Really?

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