This Is Why We Can’t Have Nice Things
A student gets handed a new DA40 NG for his first solo and the engine quits on takeoff because the mechanics installed the wrong induction hose. And no, a pilot shouldn’t be expected to know that.
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.
Faith.
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.