Pontifications: The nuts and bolts of air disasters

March 9, 2020, © Leeham News: Commercial aviation accidents are high profile news events.

By Scott Hamilton

These happen rarely. Many times, a lot of people are killed. (It should be noted that often survivors may outnumber those killed as safety improved.)

In this era of 24/7 cable news and minute-by minute social media, everyone wants instant answers as to causes.

Finding answers is not simple. A typical accident investigation usually takes 12-18 months before the investigators issue a final report with a probable cause.

One reason for this is that sometimes, the cause of an accident comes down to a single bolt, or even a single cotter pin.

This is where the new book, Flight Failure, Investigating the Nuts and Bolts of Air Disasters and Aviation Safety, serves to remind us of just how intricate accident investigation is.

Many contributing causes

There are many contributing causes to any accident. Author Donald J. Porter doesn’t overlook these. But he cites several accidents where improper installation of a single nut and bolt, or overlooking putting a cotter pin into a bolt, caused loss of control.

Most of Porter’s accidents date to the piston and jet-prop days. One of the crashes cited was the 1961 accident of a TWA Lockheed Constellation in Hinsdale (IL). (Accidents always draw sightseers. Dad took my older brother and me to look at the crash scene. This was my first visit to an airplane crash. It would not be my last.)

Ultimately, the Civil Aeronautics Board (the forerunner of today’s NTSB) determined the cause to be an improperly installed bolt. It fell out shortly after takeoff from Midway Airport, causing a loss of control.

There are also examples in the jet age. Allegiant Air’s near crash on take off from Las Vegas is one. The Boeing MD-80 was on a take-off roll. It began to rotate without pilot command. The pilots successfully aborted the flight. The incident was traced to an improperly installed bolt in the elevator.

Emery Air

Another jet-age incident that was not as fortunate as Allegiant is the crash of an Emery Worldwide Douglas DC-8-71.

This one illustrates how pilots did everything right and still wound up dead.

As the DC-8 was ready for take off from a California airport, the pilots did a control check. Everything worked as it should.

But immediately after lift-off, the plane assumed an abnormally steep nose-up attitude. Control was virtually impossible. As the pilots struggled to return for an emergency landing, the DC-8’s flight path zigged-zagged with up-and-down motions. Pilots tried and tried, but the plane crashed into an auto salvage yard adjacent the airport.

The NTSB investigation determined that a bolt, installed without the locking cotter pin, worked its way loose and fell out during the take-off roll. Three pilots died. So did Emery Worldwide. The investigation revealed systemic safety problems. The parent company shut down the airline.

This accident was features on the program Air Disasters.

Other accidents

Although the focus of the book is on nuts and bolts, Porter recounts the Boeing 737 MAX, American Airlines and THY Turkish Airlines DC-10 accident and other incidents and crashes.

This is a short book, less than 200 pages. Although, as noted, most accidents date to propeller days, it’s clear that today’s jets are not immune to the nuts and bolts of air disasters.

The book is available through Amazon and elsewhere.

26 Comments on “Pontifications: The nuts and bolts of air disasters

  1. Not quite a single bolt accident, but still highly unusual. In the 1960s JAL DC-8 crash landed in the bay on final approach to San Francisco. You would think that was the end of that , but no the plane was retreived from the water and did a repair and overhaul at San Francisco before being put back into service. That could make a new book, crashed planes that flew again.

    • @Duke: Interesting idea.

      *Qantas never has had a hull loss, repairing every airplane that was involved in an accident.
      *There was the famous TWA Boeing 707 “nose job” in which the nose was blown off in a Middle Eastern desert by the PLO or similar after a hijacking. The airplane was repaired in the field and returned to service.
      *A North Central CV-580 was involved in a mid-air collision with a private airplane. Miraculously, it landed with part of the small plane embedded, repaired and returned to service.
      *A TWA 707 and a Pan Am 707 separately lost one of the wings outboard of #4 engines. Both landed safety and returned to service.

      • >*A TWA 707 and a Pan Am 707 separately lost one of the wings outboard of #4 engines. Both landed safety and returned to service.

        There are some truly stunning photos around, from at least one of those 707 incidents…

          • The plane Pan Am sent to Travis to collect the passengers had it’s nose gear collapse on the runway. So a 3rd plane had to be used.
            The engine failure that was the start of the chain of events was shown to be connected to an inspector who signed off faulty overhaul work he hadn’t overseen.

    • The. ‘Gimli Glider’ Boeing 767 that ran out of fuel and glided into Gimli disused military airfield that was being used as a racetrack . It had its nose undercarriage repaired, flown out and after overhaul , returned to service

  2. “This accident was features on the program Air Disasters.”

    This ( and other sexed up popularized media presentations ) I deem a problem.

  3. These are a good argument for …
    Digital assistants that actually TALK to the crew , as well as follow their instructions .
    The best accident avoidance systems are those that combine experienced human judgment , with superior digital operating and computing speed .

    • I would put it this is where science of what works and what does not in a cockpit and how the whole range of spectrum pilots react.

      Bells, horns, and voice have been added and they have proven not to work.

      So, you need to test.

      One that has worked (at least in Simulators) is upset training. You acualy expose pilot to extreme attitudes and its not rote, they have no idea which extreme attitude they will encounter.

      The idea is they understand the basics of recovering from anything odd, not a specific odd run over and over and over again until its not longer a test.

      A lot of Sim training prior to AF447 was take offs and landings.

      One of the reports on that said, if they can’t do that they should not be flying.
      I believe it was 3 (maybe 5) takeoff and landings were mandatory in a given period. Those are like riding a bike, you can do them in your sleep.

      What you need is a landing where an engine quits, that tests you. A takeoff just past V2 and the electrical system quits.

      We really need a stalking horse aircraft to test that in an aircraft.

      It may be that an elecric shock to the butt breaks pilots out of the stupor they get into.

      So far all the cute stuff has failed miserably, so anything has to be tested and confirmed by science and proving it or you just add another layer to the mess cockpit systems already do.

      It is highly likely its a multi discipline approach.

      Pilot may (and appear to) act totally differently across the spectrum.

      And how to deal with that? One size may not fit all.

  4. Accidents happen, they are investigated, hopefully we learn, and adapt regulations to make air travel safer.

    I see various sources reporting that the FAA is to require Boeing to separate or move wiring bundles so that they conform to current regulations.


    The regulations are there for a reason, I don’t understand why Boeing didn’t change the wiring to conform when they built the MAX …

    I see also that the UK withdraws completely from EASA on 1 January 2021.

    under Planning assumptions if no UK-EU aviation safety agreements are in place at the end of transition period.

    I am still hoping some common sense prevails, but already there are signs of questionable thinking, and knee jerk reactions to the UK leaving the EU:

    North Sea Energy Cooperation platform
    “Luxembourg argued the platform is not an EU body but an intergovernmental agreement “and if anything, the Commission should leave,” the minutes read.”
    7 out of the top 10 largest offshore wind farms are in the UK.
    Another 4.8GW installation is being planned for Dogger Bank (In the North Sea), and could eventually support more than 100GW of offshore wind power.

    • “”The regulations are there for a reason, I don’t understand why Boeing didn’t change the wiring to conform when they built the MAX …””

      Boeing was in the certification business, they didn’t care, only they needed to care about was blaming the pilots if something went wrong.
      There must be many more examples that they didn’t follow regulations. I doubt FAA/EASA checked all certification documents. How can a regulator be sure the MAX is save without checking all self-certification documents. How can airlines be sure. Did we learn something or are we waiting for another crash to get more data.

  5. Ironically, this made me less comfortable about flying in a Boeing aircraft considering their significant recent history of found debris issues, relaxed Washington State laws regarding marijuana, rumors of relaxed views in Boeing’s management about employees who use methamphetamines, and Boeing’s culture of covering up problems instead of addressing them (recent forced PR cleanup notwithstanding).

    • Now there is an interesting picture of whacked out drug laden employees cranking out aircrat.

      I think the focus belongs on managers, inspections and failure to follow process and procedures.

      But the mental picture of Woodstock has more fun appeal.

      • A well-treated workforce is a conscientous and ultimately cost-saving workforce.

    • “.. relaxed Washington State laws regarding marijuana, ”

      A carefully placed distraction afaics to depress visiblity of the core issue: A dysfunctional corporate culture at Boeing.
      ( And Boeing is not really special in its national environment. Only fall out @B has more impact.)

      You could booze up on alc all you wanted before.
      or on pain meds or similar.
      I don’t think recreational pot smoking or not makes a noticeable difference.

  6. While the single failure has a lot of simplistic appeal, it does no tell the story.

    For that fastener not to have been secured correctly is a failure of a whole system that is supposed to ensure it does.

    The complex dive into an accident often does not need that scrutiny, in Alaska its pilots do stupid things and we haven’t figured out how to stop them.

    But like the two MAX crashes, doing so does a snap shot of a system and cultures and it can (and in those cases) did reveal other short comings that have to be addressed or they will bite you latter on.

    • Ya, a single bolt does not tell the story of the failure of management to utilize Systems Thinking and implement Built In Quality controls in their processes.

      Though, in a very telling way, it kind of does.

  7. The technical causes of a crash are one thing, the reasons for technical mistakes are another. Asking “why” five time can get to some pretty fundamental issues quite quickly.

    Sometimes I wonder these days whether there’s any point looking for technical or piloting shortcomings when the real underlying reasons why a crash occured are more and more likely to be profit motive and / or politics. If investigators keep having to say “culture”, “cost savings”, etc and nothing ever changes, there’s little point investigating more crashes.

    I don’t think we’re quite there yet, but we are at a tipping point for the industry. For me a lot hinges on the manner in which the MAX is returned to the sky (or, if appropriate, kept on the ground).

    In my opinion a software fix as the only fix for the MAX is inexcusable, especially when it’s basically fully acknowledged that the 737 airframe is far short of what human endeavour can achieve. Saying it’s “safe” ignores the fact that in many aspects of design there’s 50 years of progress that it doesn’t have, and not just in flight controls design.

    • In February 2020, three Senate Transportation Committee members introduced a “Restoring Aviation Accountability” bill, which would specifically require implementation of the Joint Authorities Technical Review’s recommendations, and more generally would set up a commission to review the FAA safety delegation process and assess alternative certification schemes that could provide more robust oversight.

      • Leon, that’s a very encouraging thing, and if that’s what happens I suspect that’ll have to do. I notice that the 3 senators are all Democrat, but it’s a Republican majority Senate – does that mean it enjoys bi-partisan support?

        My point about asking “why” begs the question, how did the FAA get to be the way it was? The answer to that question is not covered by the JATR report, it’s entirely related to US governmental politics. Changing that as required is probably fundamentally impossible.

        For the interests of balance, I’d best say that I’m not entirely encouraged by the increasing role the EU Commission plays in the running of EASA, or by the UK’s withdrawl from the EASA (pretty sure UK Gov has no idea how large a job being a civil aviation agency is). This sort of role should be wholly protected from and thoroughly independent of politics.

        • Won’t it be the other way around…the senior staff at EASA are predominately British and the they will return to the UK CAA?
          After all a reciprocal recognition agreement like that with most Western countries means they won’t have run a certification from scratch

          • It’s too early to tell, it’s been only a weekend and bit since the announcement.

            But I think it’s fair to say that whatever it is the UK gov thinks it takes to set up a world leading, properly staffed aviation authority, they’ll be a long way short of the funding it’ll actually take. That could mean it’s a dead duck of an idea, if they baulk at actually funding it properly.

            Afterall, borrowing someone else’s rubber stamp is cheap; making the machine to make one’s own is a lot more expensive.

            The bulk of the personnel may or may not be British, I can’t tell. One thing I do know is that they’d be returning from jobs with nice, juicey European-scale salaries to sign on to the books of the British Civil Service. It’s going to be a painful pay cut. A lot of them might decide to cash in their nice fat pensions and quit the profession.

        • Yes very encouraging Matthew, but is it only a game (I think the TAB was only a game).
          About EASA I have doubts sometimes too, but I think they won’t accept a software fix only after fight testing. We will see, I’m sure there are some stricter regulators than EASA.
          And in the end the passengers will decide which airline they use. I was in church last week, it was very empty because of Corona. People care, passengers will care.

          • I agree, I think that at least in the short term EASA will play this straight down the middle, nice and proper.

            My longer term concern is that the EU Commission seems to be wanting to drag more and more non-EU organisations under its own umbrella. If EASA end up being answerable to the EU Commission, then it won’t be as independent of politics as it needs to be, and that’ll simply set up the world’s industry for a permanent trade war between the US/Boeing/FAA and Europe/Airbus/EUASA. It won’t be possible to demonstrate that when one regulator says “no it can’t fly”, it’s been said without any thought of trade / business / politics.

            Between themselves the EU and the UK could end up wiping out European representation at the very highest levels of world aviation governance.

            Another good example of politics getting in the way is the European Space Agency. Previously nothing to do with the European Union, it is now being dragged into the EU Commission’s clutches.

            The ESA head has just resigned in protest at the state of affairs seemingly stoked up by the EU (or its member states); he’s been staunchly sticking to the ESA’s precise remit (which includes keeping doing business with the UK), but it seems that the EU wants to snaffle ESA for itself and expel the UK from it. Quite how that’ll go down with Canada (another non-EU member of ESA) I don’t quite know.

            It’ll be anyone’s guess as to what’ll be left of ESA by the time they realise that one of the major contributors is no longer contributing, and all the others are broke.

  8. A close call as the nearly new Pacific Western 77-200 with a missing engine bolt, due to nut not tightened/safetied properly in the facgory..

    In the hanger a few hundred hours after delivery – probably for a B check, an inspector rubbed his back against a cowling while waiting for a mechanic to finish a task he had to double check.

    Shouldn’t be that flexible! Digging revealed no bolt.

    The engine had three mount bolts, that forward IIRC one was installed head down in tension, due geometry of the installation. Departure of the JT8D-9 engine mounted close up to the wing could have torn enough flap off to cause serious roll asymmetry.

    Boeing hosted an employee dinner for the inspector, both because he deserved recognition and to give a message to production employees about the real world.

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