PMA doesn’t help either in most cases because there simply isn’t the market nor the qualification to do proper R&D. The risks of using different materials/processes is large and there is no return on substantial R&D which is why you get the same 1950 metallurgy from the PMA manufacturers.
That is true; a PMA part has to be provably the same. But it is easy enough for a US company to get an STC for an improved cam follower. After all, somebody got an STC for a substantially improved camshaft with an internal oil feed. I have seen STCs for “improved” air filters for the TB which I don’t see as needing substantially less due diligence. Rightly or wrongly, the engine business has a dirty reputation and the market is ripe for “improved” parts. “All” somebody would have to do is show that the originals are crap. It would be easy to show that the metal or the heat treatment is crap. Yet nobody seems to be able to do it, despite the overhaul parts market being worth many $ millions. Are all these companies stupid, or do they know that there is no data proving the metal is crap?
Lycoming have gone to roller tappets which now makes it a declining market anyway, but these issues have been around ever since these engines have been around. I know people fly less today than in the 1960s but IMHO not enough less to suddenly make the engines fall apart at the interfaces.
A revision of a Mercedes car engine (i.e. improving an existing model) costs them north of 1 billion Euros in R&D
I think that is PR talk – like saying that the $750k price tag on a certain new plane is due to product liability 
Especially as nobody has managed to locate the relevant item(s) in the companies’ accounts 
But why an earth should one have to send of oil to be analysed?
It is just this
Some people prefer to not know – they just enjoy flying. Happens in the medical business too.
I can understand a flying school not bothering, because they spend some 99% of their time in easy reach of a field, and catastrophic failures are rare. The only time the school needs to worry is if at the 50hr check the engineer opens the filter and finds it full of metal and risks the loss of future business by refusing to release it to service, and then they are stuck with a grounded aircraft.
Actually schools are probably OK because even UK ones fly a lot through the year.
Lycoming have gone to roller tappets which now makes it a declining market anyway, but these issues have been around ever since these engines have been around. I know people fly less today than in the 1960s but IMHO not enough less to suddenly make the engines fall apart at the interfaces.
In the 60s/70s cars would fall apart every other week. I have memories of my dad spending every weekend in the garage trying to fix the Renault… Cars have evolved greatly, airplane engines have at best not evolved at all. We simply have different expectations today, rightfully so.
think that is PR talk – like saying that the $750k price tag on a certain new plane is due to product liability
Obviously companies like to declare everything as R&D, down to cleaning the toilet. However, it does cost massive amounts of money to make changes to engines. A lot of time spent on dyno tests, very large test runs and a lot of trial and error attempts. Even car companies share engine designs because they cannot afford the R&D.
In the 60s/70s cars would fall apart every other week
I don’t think it was due to catastrophic engine failures. Those have (for many decades) been extremely rare with cars.
One could not fix an engine anyway in a garage. Maybe the ignition system or the carb.
Most of it was stupid electrical failures, compounded by the fact that a modern car will just stop when there is any electrical problem to do with the battery or the alternator. The industry invested a lot of effort into improving the electrics from totally dirt cheap crap and awful and unable to tolerate water, to merely dirt cheap crap and awful but mostly OK when they get wet.
Then a lot of it was due to crappy mechanicals outside the engine. Loss of coolant was common, and evidently still is – my Toyota got that once. Crappy rubber hoses.
Don’t car companies share engine mfg too? I would think the VW/AUDI 2 litre diesels all come from the same place.
I am sure you would get a ~100% failure rate on car engines within a year if you ran them at 65% of max rated power the whole time. It’s not possible to make this comparison. The car industry has a vast experience from actual usage, and they make sure the product is “reliable enough” in that usage.
Not that I think there is much common ground either way between cars and aircraft, but most American cars of the 50s and 60s were not unreliable. I remember a coast to coast (and back) trip in a very basic six cylinder ‘64 Chevy in which no repairs were needed. Call that 5000 miles. It has occurred to me however that the relatively recent increase in European car reliability (since the mid-80s, although I think of mid-90s as the peak period) explains something about attitudes of those who drive them. I’ve spent a lot of time fiddling with all of them so I think I’m beyond thinking about any of it any more than necessary.
My never overhauled 1971 O-320 Lycoming tested at 78/80 compression on one cylinder, 79/80 on the others yesterday. My 140,000 mile turbocharged Japanese car is still on the original belts and hoses. I’m only really interested in spending money on what works for me, and both those are pretty good examples.
Peter, Once again refer to my post #118 it has all the details. I stated that, filters were cut open and oil Analysis was done by Blackstone Labs. Whats the point of cutting open a filter without looking for metal etc. To expand on my statement I change my own oil and cut open the filters myself and inspect for metal. On the rare occasion that someone else changes the oil I make sure to ask if they cut it open? Then ask did they find any metal?
If I had metal in the filter I would look for the source no matter how little. Fortunately up till now have not had any metal. If a mechanic said that to me that would be the last time he would have my plane in his shop.
“I am sure you would get a ~100% failure rate on car engines within a year if you ran them at 65% of max rated power the whole time. It’s not possible to make this comparison”
Yet MB derived diesels are run at close to 100% power to TBR and we’ve yet to hear about a “100pct failure rate”.
I am sure you would get a ~100% failure rate on car engines within a year if you ran them at 65% of max rated power the whole time.
My friends in car engine R&D (everybody here besides me works in the car industry) tell me this is wrong. With the right cooling, they can sustain high power ratings almost indefinitely and do so on the test stands. It’s just a matter of dissipating the heat but there is nothing that makes aircraft engines exceptionally capable of delivering high power outputs over a long time. It’s 1950s technology, equivalent to what a 1950s car engine was.
It’s 1950s technology, equivalent to what a 1950s car engine was.
I think it’s 1940s technology, developed for aircraft and very effective in that role, with essentially nothing in common with car engines past or present. Cars are today IKEA throw away technology, which would be inappropriate for any long life privately owned machine. I would and will never buy car technology for a plane, ever.
“Effective” only if you use it one hour per week, at half the power it’s supposed to deliver, said power set with exacting precision on the basis of a visual evaluation of RPM drop on a equally highly accurate tacho, and then usable only between 5 and 35C otherwise it either won’t start or overheat on the ground if you taxi more than 5 minutes.
