This Is Why We Can’t Have Nice Things


I really should stop reading so many accident reports, but I am suffering from some sort of psychosis that prevents me from quitting. Just as soon as I think I’ve reached step two of the 10-step withdrawal process, I’m clicking on another one and plugging the details into my database.

And just as soon as I think I’ve seen the most bizarre thing imaginable, I find another one that plummets below even that standard. Like this accident (PDF). I’m working on a follow-up report on the engine failure video we published last week. I unearthed this accident because I wondered if there had been any failures of the Austro AE-300, which I consider to be the most refined piston engine in general aviation today.

The almost comically sad summary is that this crash happened to a 14-hour student pilot on his first solo. The engine rolled back to one-third power because the shop replaced two induction hoses with the wrong type, one that had an inner lining that wasn’t stitched. This caused the hose liner to collapse and starve the engine of air. The airplane did not come from the factory with that hose. The long and the short of it is we handed a well-engineered, modern airplane with a superb safety record and an engine to match to a 25-year-old student pilot who got an e-ticket ride through power lines and drainage ditches because mechanics installed the wrong hose. On the upside, it looks like the student was well trained and performed admirably.

And let me interrupt the flow of this commentary for a brief rant. This accident still doesn’t have a final probable cause from the NTSB. It occurred exactly four years ago almost to the day and is still in progress. Frankly, this is pathetic. The NTSB should be doing better than this. A lot better. When you read it, you’ll realize that the G1000 in the airplane provided excellent technical data and an engine inspection filled in the rest. Now, back to your previously scheduled blog.

And this week, I was asked to discuss the engine failure video with a group of California pilots, one of whom asked how you’re supposed to tell if a mechanic has improperly torqued a rod or a cylinder base nut or bolt. If the NTSB reports are accurate, this is a frequent cause of engine failures. My answer is to babble incoherently because I don’t know. There is no way to know if a rod cap bolt either wasn’t torqued or is coming loose. If you’re really obsessive, I suppose you could buy a cylinder wrench and check the cylinder base nuts. I have never done this and probably would not because I prefer the religious method.


No, not praying to the Almighty for my salvation in the event of an engine failure, but faith that the shop I’ve engaged generally knows what it’s doing, always does that and has a track record to prove it. A track record is not necessarily blemish free, because A&Ps and IAs are human and they make mistakes. Mistakes are forgetting to log something correctly, missing an AD or forgetting a ground wire. It happens.

For major engine work or overhauls, I have no means of second-guessing that work. I rely on the shop’s reputation. It has generally worked, but in the engine failure video, the Lycoming engine that failed and put our Mooney into a swamp was a factory engine, so there’s that. Overhauls I’ve bought from Penn Yan Aero and Zephyr Engines have been good soldiers. So has the engine in the Cub, from Don’s Dream Machines. With evidence of proper torque throughout, I would, naturally, go back to those shops.

None of these shops were named in the many dozen accident reports I read on maintenance-caused crashes. Quite a few lesser shops were. If I were to generalize about what they did wrong—and this topic eludes broad generalizations—it’s that they did stupid stuff even I know not to do. For example, using sealants on crankcase halves when the overhaul manuals say not to do this. Or not following the prescribed torque tightening method and sequences. Those things are there for a reason.

At most shops, you’ll see a step-by-step assembly checklist so that nothing is missed and nothing is improperly installed. The factories now have at least some of this computerized, including automated recording of torque values on critical fasteners. This is just one minor example of things the factories have done to minimize manufacturing and assembly errors.  

It’s a different story in the field. And I don’t want to overstate the case here by suggesting airplanes are raining from the sky because of incompetent mechanics. That’s simply not the case. The overwhelming majority of maintenance is done correctly and professionally. It’s just that the egregious errors often get their own NTSB numbers.

Owners can do their part by tending to maintenance in the first place, repairing stuff that should be repaired and being a little careful about deferring too much. When you decide to skip replacing a cowl fastener, just make sure that four more aren’t about to go off duty. Because the minor things so rarely cause accidents, there is tendency to ignore them to the point of complacency. If you can’t afford to or don’t want to do the necessary maintenance, you’re better off not owning an airplane.

No Aero

When I got the email canceling Aero in July for the second year in a row, it was actually a relief. First of all, it was jammed up against AirVenture and I wasn’t sure I wanted to do the international travel anyway. Aero is, by far, my favorite of all the shows. It’s quiet, focused and they have beer and coffee in most of the booths. You can at the same time be drunk and over-caffeinated and on a sugar high from all the pastries you swore you wouldn’t eat this time.

I don’t know if this is the right thing to do or whether it’s an overreaction. The show is held in a complex of indoor, well-reventilated halls, but indoors nonetheless. It seems inconceivable to me that with the international crowd Aero attracts, there would be no COVID-19 transmission. But would it be a little or a lot? If it’s a little, is that worth the risk? If it’s a lot and there are deaths, is that the price we have to pay to carry on with these shows?

For me, after writing the obituary of my friend Mike Collins six weeks ago, the answer is no, it’s not worth this risk because there are other ways to do this work and this job. The CDC tells me my risk, as a fully vaccinated person, is 0.005 percent of acquiring in infection and lower than that from dying of it. That’s vanishingly little, but much remains unknown about how variants may swing that number. I don’t mind hanging back for a while.

We’ll eventually get back on track with these expos, although after a two-year layoff, Aero may look a little different. Sun ‘n Fun, which I did attend, had a slightly different feel to it. But I spent 90 percent of my time outdoors. Can’t do that at Aero. I’m glad it was decided for me.

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  1. With respect to the DA 40 engine fail the very unlucky student pilot did the right thing. He did not try to turn around and kept the aircraft under control until it stopped moving. The instant the engine rolled back the insurance company bought the airplane and the pilots primary task was to arrive back on the ground without injury. This was a good news story.

    I would be interested in Paul’s thoughts regarding engine failures caused by faulty maintenance, vs engine failures after pilots went flying with known defects. My suspicion is there is considerably more of the latter then the former.

    I own 2 airplanes so I am very aware of how expensive it has become to properly maintain an aircraft. I also see a significant number of airplane owners that look like they are scrimping on maintenance.

    Engine failure accidents seem to be increasing, but the plain fact is that many of these could likely have been prevented by a greater commitment to not let maintenance slide and not live with known defects.

    • I didn’t sort the data for trends in pilots knowing about defects versus other failures. If pilot-caused fuel-related stoppages are eliminated, I would say the majority of the maintenance-related accidents were not caused by known defects, but stuff the shop did or didn’t do. The above accident is an example of this.

      If we want sophisticated, efficient powerplants–and the AE-300 is that–then mechanics have to learn to maintain them. The hose in question was a numbered, approved part. If a mechanic replaces it with a generic part, he or she needs to know what the implications of that are.

      The Nall data shows that maintenance-related crashes have been rising over the past five years. Engine-related accidents are the lion’s share of these mishaps, so they may be rising. I didn’t sort the data to confirm that, however.

  2. I find the almost daily stream of reports of engine failures disturbing. At my age (mid 70’s) I tend to be more conservative than I was in my 50’s. Even then, after one OMG experience hang gliding, I made the decision that it was more important to maintain my physical integrity (and earning power) rather than satisfy my brief desire for excitement. Perhaps I should get trained and licensed as an A&P. Or, just buy a three monitor, VR capable, computer system and “fly” virtually.

    • “Perhaps I should get trained and licensed as an A&P.” Rich, unfortunately the FAA has made it almost impossible to do so if you have a full-time job. Even if you are retired, the time to acquire the experience for qualifying for the license is enough that you may be too old to fly by then. I, and others here, have railed against the problem and suggested the FAA promote training to allow plane owners to legally work on their own aircraft, but no others. Sadly, the odds of it happening are about the same as Paul’s dying from COVID after receiving the vaccine.

  3. The chinese have a word for it which springs out of communist factory mind-set, which roughly translates as “good enough” to leave the factory.
    It is why my sister and brother in law were stranded in the middle of the African bush for a night when the extremely cheap bolt used to hold the main pulley assembly of the Chinese pick-up they were driving shattered, leading to what my sister, a nurse, described as multiple organ failure.
    The mechanic who cut the air tube out of what they found lying around instead of ordering the part or double checking, obviously thought too it was “good enough” for him to get out of the shop and home for a beer. Sometimes communists and capitalists are just the same.

  4. “asked how you’re supposed to tell if a mechanic has improperly torqued a rod or a cylinder base nut or bolt. ……… My answer is to babble incoherently because I don’t know.”

    My answer:
    Don’t worry about the nut or bolt Just assume that the engine will quit and have a plan of action. Execute the plan and walk away from the wreckage.

    • Utterly ridiculous reply, of course. he only way you can do that is to fly from long runways and depart non-standard in circles over the airport, don’t fly over forest or rough terrain and arrive over the airport high and circle down. Try that at VNY.

      • Though having a proper takeoff briefing and planning your route for contingencies will go a long way toward mitigating the risks of engine failure. Not all of them (some maneuvers by their nature leave very little room for engine failure, like a short-field takeoff in some multi-engine piston aircraft), but at least a good number of them.

        • Gary, I absolutely agree with your first sentence. Second part, not so much. When it comes to multi-engine airplane operation you suddenly have a whole new set of hard performance figures. You either fly out of it or you don’t. In single engine airplanes there are no options. You’re or up, or down. And Grant’s assertion that you will walk away from the wreckage if the flight was properly planned is, to me, still not a fully understood statement.

  5. “Ignorance Is Bliss”… Most pilot/owners prefer not knowing. Drop the keys off with the maintenance shop and wait for the call that the plane’s Annual is complete. Maintenance shop mechanics are not paid to study manufacture manuals. It takes several hours to learn a new engine and/or aircraft. Should the aircraft owner pay or should the mechanic study on their own time?

    Some mechanics work directly with the owner/operator by educating them about what an Annual is and how to use the aircraft manuals/publications. Every aircraft owner should have a copy of AC 43.13 and study it like their life depends on it.

  6. Joe

    The good news is that engine failures where there are no good options to land are still surprisingly survivable IF impact occurs at a lower speed with the aircraft wings level and a level or slightly nose up attitude.

    This is why most people survive crashing into houses, dense forest, large rocks etc etc. 60 kts to 0 knots takes 24 feet with a steady 9 G de acceleration. Even a few feet of space for de acceleration greatly increases survivability. This is why the steep nose down hits are almost always fatal.

    Paul, what I was thinking of was more along the lines of pilots who choose to minimize maintenance and then suffer a failure. The poster child for this was a accident I am aware of where the airplane suffered a catastrophic internal mechanical failure and instant total power loss. At first glance you would say that this was not foreseeable, but the pilot insisted that an oil change was only required even 100 hrs because the airplane had a oil filter. However he only flew 30 hours a year and therefore he would not pay for an oil change at the last 3 annual inspections. I believe it is likely that if the oil filter had been examined at the last inspection which I believe was shortly before the accident flight it is likely there would have been signs of engine distress

    It is impact f these kinds of owner driven maintenance decisions to save money, that I wonder about.

    Finally as a general comment I would suggest basic mechanical competence is is fading as we live in a repair by replacement world for virtually everything we own. My personal experience is that light airplane system understanding is often very weak in GA pilots and so they miss the clues that are often present before the catastrophic failure.

  7. Looking at the photo of the hose in the NTSB docket linked from the report, it looks like the hose is aircraft type orange silicone, of the type commonly used for induction hose. So this probably wasn’t some off-the-wall substitution of Home Depot crap for aircraft hardware. Unfortunately, that “aircraft quality” material appears to have been designed to carry air at pressure higher than ambient, and when used for air at a pressure lower than ambient it collapsed. Personally, I’d classify this one as a failure of imagination more than anything else. The mechanic failed to imagine that stuff they were familiar with, that is perfectly adequate most induction applications, was not appropriate for all induction applications.

  8. As an A&P of over 50 years experience, I URGE your non-A&P readers to stay away from cylinder base nuts and don’t go buying cylinder base wrenches to see if things are tight. Mike Busch has a LOT to say about this sort of thing and even he doesn’t fiddle with cylinders. Unless you want to hose up an engine, start a leak (requiring RTV to fix it [kidding]) or otherwise cause issues, keep your mits off those nuts. Leave this to your mechanic. Make sure they have the appropriate tech data for the engine in question, the appropriate wrenches and torque measuring devices and that’s that. After that — as you said — leave it to Faith. And if your mechanic thinks it’s OK to pull more than one cylinder off your engine, find another mechanic. There’s a process to ensure loosening cylinder bases and through bolts doesn’t cause subsequent issues. Bottom line … this is serious business. I have never actually seen an engine problem due to loose cylinder attach hardware but PB is “the” man when it comes to airplane crash analysis so … if he says it happens, then it does.

    This is one of the reasons that Rotax INSISTS that anyone doing maintenance on their engine has been through their appropriate engine schools. Even an A&P isn’t ‘technically’ allowed to touch them. Anyone flying a Rotax better make sure their mechanic has the appropriate training certificates. Same story, different flavor.

    Two weeks ago, I did a Flight Review in a 172 with a nicely remanufactured Garmin panel in it. Right away, I see things wrong with the instruments. The operator finds out I’m an A&P (but away from where I do that sort of work) and he wants me to spend an hour and fix all the crap that was wrong with the airplane. This is typical. If you own an airplane, there will be times when you have to part with some Benjamin’s to make sure that it’s safe and legal. If that’s not something you can do, take up boating.

    • “I have never actually seen and engine problem due to loose cylinder attach hardware…”. My airplane experienced a loose cylinder shortly after the previous owner had the engine overhauled. Fortunately both the plilot and engine survived the incident. I have wrestled with whether to pull the #3 cylinder that seems to have developed chronically low compression of late. Borescope and oil analysis reveal nothing amiss, but at 1,600 hours (and 26 years), I wonder if an overhaul may be preferable to messing with the cylinder. I have read several Mike Busch articles and his book cautioning against cylinder removal. Maybe I’m just being paranoid.

      On the subject of pilot assisted annuals, I am blessed with an A&P/IA that allows me to do most of the grunt work each year. I learn something new about the plane and its condition each time. I must admit that the temptation to substitute hardware store items for aircraft grade components is always there, but his oversight keeps me on the right path in that regard. That, and Paul B’s recurring reviews of NTSB reports about what happens when you go over to the “dark side”. 😉

  9. The sudden, unforeseen engine failure is a rare phenomenon. NTSB reports are rife with engine failures preceded by puzzled pilots wondering about, then dismissing strange indication, noises, vibrations, etc. Engines talk–we just have to listen. The preflight and engine runup gives us the opportunity to listen. Don’t squander it by ignoring what your engine tells you.

    • My wife has heard me say hundreds of times that … “Things mechanical talk to you … you just have to learn how to listen to them in their language.” Good advice for everyone. It’s not JUST engines … it’s everything. Fortunately for me … the last thing that is failing is my hearing … I can hear things most people can’t see. 🙂

  10. I agree completely with regard to the NSTB. There is no reason or excuse to drag something like this out for 4 years. This only reaffirms the point that critics make of government agencies. Slow, cumbersome, and not results oriented.

  11. Kudos to that student pilot! As far as owners doing their own maintenance, I disagree as many are not capable, but some are. Over the years as an A & P/IA I can cite many instances of where an owner puts automotive brake fluid in their hydraulic system, or decides to remove a slightly corroded bolt/fastener and replace it with a nice shiny one from the hardware store, or shines up that bolt on a wire wheel removing the coating. Then there’s adding un-approved oil or fuel additives. Sure, they could be taught, but there’s a lot to know about airplanes in general and thats why it takes so long to get an A & P. I work with owners during an annual so that they can see what goes on and learn from that. And if you’re working on a 50 year old airplane, don’t expect to be able to order a fuel or hydraulic hose, it will have to be fabricated. TOM C -BUFFALO

  12. Paul, your quickly becoming my favorite AvWeb author with well written articles like this one. Kudos.. It also brings to mind the round table discussions at the local airports about the “impossible/improbable/high risk turn” attempted after takeoff encountering an engine failure. Many have practiced, but few have thought through the details of what’s happening and the probable human factor elements in that equation. This 14 hour Student Pilot, and your videos/articles should give all pilots pause. And that, is what will open the safety margin for all GA related accidents.

  13. As an A&P, pilot, and aircraft owner, I have found that many aircraft owners are simply not interested in knowing their aircraft systems or maintenance schedules other than the time and cost for the next upcoming annual. Aircraft maintenance is the “responsibility” of their A&P. I believe this mindset comes from several factors.

    Many people associate anything mechanical and maintenance requirements with their personal car or truck experiences. Very little on modern vehicles can be practically owner maintained. Even oil pan drain plugs often need removal of a myriad of plastic fairings. Need an oil change? Go to the nearest “Jiffy Lube”. Spark plugs rarely get changed with vehicles running 200K+ on the original plugs. Air filter needing service? Wait for the vehicles message center to tell the owner or if ignored, eventually, the check engine light comes on. Even then most will continue to drive the vehicle because it still runs well enough. Consumers have become so lazy about basic maintenance, most manufacturers have replaced the transmission dipstick with a sealed plug. Most have no clue that the trans fluid and filters needs regular changing. As a result, seal the trans, limiting outside contamination with most transmissions running 150-200K on the original fluid. Cars and trucks have improved so well that outside of the most basic fluid changes, combined with everything computerized, in addition to so much hardware crammed into a small space to facilitate daily operation of a 20 year old or newer car/truck, most will run with virtually no maintenance at least 100K. With rudimentary maintenance for 200K, and with someone who really has educated them selves on the systems and has the capability to diagnose and repair the ailment 300-500K easily. The bet by the manufacturer is most will trade before they repair.

    Schools do not encourage vocational skills. Basic shop skills are not taught anymore. Military recruitment videos promote push a button and move a stick while staring a computer monitor as the two primary skills one needs to maintain and operate modern weapons of warfare. Need to find an answer to who makes the best pizza, the location of anything, and the best repairman for ( fill in the blanks) ask Alexa or post on one’s FB page soliciting for opinions. The societal result has been…Google or YouTube it…looking for an immediate answer for an immediate problem. Therefore, anything that happens prior to the vehicle or consumer product failure that may or may not “talk” to you its symptoms prior to failure are not even recognizable to many.

    Now this consumer mindset, conditioned over the last couple of decades, enters into the aircraft market. Now, we have to deal with “ancient” magnetos, mechanical fuel injection, carburetors, wires, hoses, exhaust systems, mechanically operated turbo chargers, mixed into modern, sophisticated glass panels, airframe parachutes, including a mix of composites with aluminum, fabric, and tubing airframes. Even the “modern” Cirrus is now almost a quarter century old. And the Bonanza is well past 70+ in production.

    So the consumer leaves this mixture of old and new to the “expert”…the A&P. It is getting tougher and tougher to be the maintenance “expert” as the A&P. Old school maintenance skills combined with state of the art modern mixtures of aircraft manufacturing techniques, along with the staggering avionics advancements makes it almost overwhelming in the wide knowledge base that is required by the FAA regs and expected by the consumer. This is why I see many shops specializing in a single brand or in many cases a single model of a particular brand.

    To be proficient in cylinder R&R on a Cub or a modern 550 powering the latest and greatest SR22 requires a lot of model specific experience. A cylinder change on one airplane is a lot different process in another. But, to many aircraft owners, their expectation is if one is an A&P, they know everything about every airplane. And the manufactures as well as the FAA expect likewise. Yet the average A&P makes a lot less than the average dealership line mechanic.

    We have entered a new age of consumer expectations combined with a fleet of new to 85+ year old airplanes that can have the sophistication in many areas of modern avionics combined with type/model specific old school knowledge of simple or complex systems. The demands on the A&P today is enormous, largely misunderstood by a large number of aircraft owners, and regulated by the FAA that has few and fewer abilities to keep up with regulatory and oversight that this blend of old and new demands.

    How does the GA or even commercial aircraft industries recruit for candidates to enter this age of unrealistic expectations? And how does aviation begin to educate the end user that they need to be more proactive in gaining basic systems and maintenance skills instead of handing this increasingly enormous responsibility over entirely to the A&P?

  14. I suspecting many of the commenters here are not schooled on a category of aircraft described as “Amateur Built”. Amateur Built aircraft are built and maintained by NON-A&P mechanics. There’s ten’s of thousands of them. Many of these aircraft are the finest examples of workmanship found anywhere.

    Many of these people who couldn’t tell you where the hood release on their car is five years ago. Now they fly over a 100 hours a year in an award winning 170 knot Van’s aircraft. Many of these folks have built STOL aircraft that can out perform any certificated aircraft built and maintained by the best A&Ps. Amateur Built aircraft can be at both ends of the spectrum in standard of build. I think that’s a good thing that each of us can decide to do it our own way. I think they call that “Liberty”.

    • Klaus, I as well as several other commentators have built, flown, and maintain Experimental/Homebuilts. I agree that this portion of aviation has provided knowledge and experience to many builders who had previously no experience maintaining anything. Sport Aviation is filled with such examples of exceeding craftsmanship. But at the end of the day, it takes an A&P sign off for the yearly conditional inspection adding a whole new additional skill sets needed to determine airworthiness.

      For those who build their airplane and gain the Repairmen’s certificate, they are the best qualified to do the conditional inspection on the airframe and avionics. But do they have the skills needed to make the same determinations on the engine if they did not assemble them? Many of those incredible Van’s creations have factory built engines. They were installed because of the lack of engine assembly knowledge in many cases.

      However, the vast majority of this ever expanding fleet has changed hands with many buying these airplanes with the same mindset and experience level I commented on that you are addressing. Once again, an additional regulatory, liability, and training burden that is placed on the A&P. I have no problem inspecting some Experimentals. However, there are many I would not get involved with for a myriad of reasons. Therefore, I would not want my name in those logbooks.

      • Every time I think about the five year + long effort to provide the FAA with a regulatory recommendation and framework for the Part 23 Rewrite a few years back, it makes me irate. There were about 40 to 50 people who met for years, actually did a decent job and then gave it to the (then) Small Aircraft Directorate in KC only to have it basically ignored. If adopted, the FAA could have literally copy/pasted what was written. THE most important part of that effort was the recommendation that certificated aircraft could be relicensed in a “Primary Aircraft” category (not to be confused with today’s Primary aircraft category). This would make them — ostensibly — an E-AB with all the benefits that category affords. AND … it was a two-way street … such a converted aircraft could be converted back to certificated IF a survey was done by a DAR. Annuals on such a relicensed aircraft could have been done by an A&P or owner if they took the appropriate training. I can’t remember the Appendix of the paper that was written but it was perfect for many qualified owners.

        And what did the mythical “we” get instead … NORSEE. Dynon/EAA was the first to use that with the “surprise” installation of a D100 in a Cessna at a Sun n Fun a few years back. But I can’t help but think of what COULD have been if the paper had been adopted, as written. It’s better than nothing but it COULD have been SO much better …

    • Both Klaus and Jim bring up salient points on either side of the aircraft ownership/maintenance experience.

      When I was in an aircraft partnership and the other owners wanted to “help” doing an annual, I finally got to the point where I shoo’ed them away and told them I’d call them when it was done. Some of them brought their left handed screwdrivers and I knew I was in deep doo-doo trying to keep track of what they were doing. Oft times, they’d take fasteners out and not keep track of them, as an example.

      And I’ve seen E-AB airplanes that were SO impeccably built that they left me speechless. As you say, I recently saw an RV-7 that was that way … knowing I likely couldn’t match such worksmanship. That said, MOST of the people who do these airplanes aren’t 20 years old … moving back to Jim’s story. There’s a few but not many. It takes years of patient learning to arrive at the point where one can do such work.

      The “Dirty Jobs” guy, Mike Rowe, talks about being able to work with your hands and have a ‘noodle’ in tune with all things mechanical. When I grew up, we were SO poor I had to build my own scooter out of a 2×4, orange crate and half of a clamp on roller skate. I even figured out how to put a light on the thing. That ability has served me well throughout my life not to mention all the $$ it has saved me over time. If I could change one thing about the way today’s schools teach, it would be forcing them to return to the days when home economics, wood and metal shop, auto mechanics, et al, were taught. Heck, kids can’t even manage money or use a checking account properly, oft times.

      Now that I think about it … this is probably why Airbus’ are SO automatic … you just point the thing and it takes you there … talking to you the whole way. 🙂

  15. Reading what you said about how procedures are there for a reason made me remember reading the bit in Yeager’s autobiography where he talks about the flight in the F-86 (I think it was) where the controls locked up completely. He was doing a flight specifically to test for problems, because there had been some airframe losses. He recognized that the problem happened when he loaded up the wing with negative G, and so he unloaded it and the controls came unstuck.

    Turns out somebody at the factory (!) was putting in a set of crucial bolts upside down, because everybody knew that the head should go on the top. Under load, the wing flexed enough that the improper clearance caused things to bind.

    So, yeah. Procedures are there for a reason.

  16. I had almost the exact same thing occur with my 1946 Ercoupe a couple of weeks back.

    Only it was not an induction hose. It was a brake line. It was a lovely morning and after a 30 min flight I decided to head back to the start of the runway and take off again. I pushed the throttle in but about halfway down the runway I noted that there was plenty of noise and the instruments looked great but we were not going very fast. I chopped the throttle and we stopped without my touching the brake pedal. The brakes had locked up, not solid but enough to require at least 50% power to taxi at maybe 2mph.

    Opening the brake bleeder released the brakes and thoughtful analysis led me to conclude that the rubber hose from the brake master cylinder had collapsed internally, forming a “check valve.” This was not a 75 year old line but a new aircraft grade line no more than 10-15 years old rated for a lot higher pressure that it ever sees. When I described the problem to one very experienced A&P he nodded sagely and handed me a fuel line that had developed the same problem. My regular A&P said he had never heard of anything like that but recommended the old line be replaced with new Teflon lined armored hose; that stuff is $12.50 a foot and the end fittings are $63 each, but I payed it.

    I also study mishaps and have given college lectures on space launch mishaps. Sometimes weird stuff just happens.