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It's annoying how antiquated the engines used on these single engine planes. Continental is selling engines designed in the 60s that are just so inefficient.
by google234123 4y ago
It's annoying how antiquated the engines used on these single engine planes. Continental is selling engines designed in the 60s that are just so inefficient.
- _ph_ 4y agoI think that is one of the reasons why the upcoming electric small planes are such a huge thing - getting rid of not only combustion engines, but very old and inefficient combustion engines. Could be a real game changer.
- jacquesm 4y agoThey'll end up with a fraction of the range/payload of the old planes.
- _ph_ 4y agoYes, of course. But the range (1-2h) might be just enough for a lot of szenarios.
- ElevenLathe 4y agoMaybe that's fine if the point is just to go up on a Saturday for fun and land at the same field you took off from.
- Toutouxc 4y agoI'd literally fly a bicycle with wings for fifteen minutes at a time if that made [fixed-wing] aviation more affordable. I live in one of the better-off eastern-bloc countries and I make significantly more than most people I know, but getting a PPL would almost certainly ruin me financially at this moment. I know that paragliding and hang gliding exist, but those are a bit out of my comfort (and safety) zone.
- jacquesm 4y agoThere are clubs that own small aircraft that you can fly, I've done some time in these: https://en.wikipedia.org/wiki/Ikarus_C42 https://en.wikipedia.org/wiki/Ikarus_C42 Technically it is a microlight but top speed and handling are much closer to a regular GA craft. I absolutely loved it and if my eyesight was better I'd definitely go for a license.
- outworlder 4y agoThere are also actual gliders (aka soaring). These are planes in all but the engine, and are pretty safe.
- Axien 4y agoBuy a Cessna 150 or 152. About the same as your bicycle and about as affordable.
- outworlder 4y agoThey are probably not going to take off (pun intended) any time soon. Just fuel reserve requirements alone are about the full range they have. I suspect hybrids will be developed first. Basically an APU sending power to the main motor + a relatively small battery. The 'APU' can be relatively compact and deliver a lot of power, with less engineering requirements (can place it anywhere, doesn't need to interface with a prop). If it fails you have some emergency battery power. Electric motors are incredibly strong and have very few moving parts, so reliability is higher. They are also light. Net net, there's some complexity and the combined equipment may be heavier (may! existing powerplants are some heavy beasts) but there's probably advantages. Certification would be horrendous, I imagine.
- AtlasBarfed 4y agoYeah BEV / Teslamania obscures the fact that what automotive REALLY should have done was hybrids from year 2005+ for virtually every vehicle as the first step. Instead, they are doing the great leap to full electric. In my vision a compact rotary (that inside-out rotary patent a few years ago looked even more promising) would recharge the battery subsystem. Or maybe a fuel cell. The same would probably work for GA. Really, hybrids will work regardless of the battery tech for the next couple decades.
- _ph_ 4y agoYes, considering the first hybrid with the Prius was available as early as 1998, the car industry should have switched to hybrids in the early 2000s. But unfortunately they didn't. Just keeping selling pure combustion engined cars was far too profitable. I think Tesla did indeed play a huge role in pushing full electric cars. Which today is of course the correct technology for most applications as it skips the combustion engine completely. Hybrid planes would be quite attractive, but of course the certification bareer which might be too large
- AtlasBarfed 4y agoI thought going directly to BEV was a good plan, but then someone on this site pointed out that if civilization needs to go to BEVs, and there is X supply of battery materials, should we use those in 100kwhr packs for full BEVs, or in 20 kwhr battery packs for PHEVs that will deliver 80-90% of trips electrified? So you effectively electrify 5x the number of cars... But, that opportunity has passed, at least we are moving towards electrification.
- nickff 4y agoThis is a product of the regulatory process. I am sure Cessna would love to sell new stuff, but it's just not worth it for them or their clients.
- mopsi 4y agoThe whole small piston-engine plane industry collapsed in 1980s because of excessive liability: https://en.wikipedia.org/wiki/General_Aviation_Revitalization_Act https://en.wikipedia.org/wiki/General_Aviation_Revitalizatio... If I recall correctly, Cessna was found infinitely liable for every plane manufactured, meaning that each new plane off the assembly line increased their potential overall liability without liability over decades-old planes expiring and decreasing it.
- mfkp 4y agoThat's true of US-based manufacturers, but foreign manufacturers thrived during that time (French, etc).
- light_hue_1 4y ago> If I recall correctly, Cessna was found infinitely liable for every plane manufactured, meaning that each new plane off the assembly line increased their potential overall liability without liability over decades-old planes expiring and decreasing it. This was a problem in the 90s. And it was fixed! Back when the government still fixed things. https://en.wikipedia.org/wiki/General_Aviation_Revitalization_Act https://en.wikipedia.org/wiki/General_Aviation_Revitalizatio...
- Axien 4y agoCessna did sell some new stuff. It all failed.
- bombcar 4y agoThe market for small planes is basically entirely gone; the entire amount is so small that they can't really get through the cost of certification for the amount they sell. Even the relatively modern SR20 uses a Lycoming engine: https://cirrusaircraft.com/aircraft/sr20/ https://cirrusaircraft.com/aircraft/sr20/ - https://en.wikipedia.org/wiki/Lycoming_IO-390 https://en.wikipedia.org/wiki/Lycoming_IO-390
- flangola7 4y agoWhy is the market smaller than in the 60s? There's more people with money than ever.
- metadat 4y agoThe cost compared to the 1960s seems to be much higher. Even for "people with money".
- 0xffff2 4y agoIt really isn't though. Yes, the GA fleet is extremely old, but the inflation-adjusted cost of a PPL is pretty much exactly what it was in the 1960s.
- kevin_thibedeau 4y agoInflation adjusted wages aren't.
- jeffbee 4y agoThese engines have parts that are interchangeable with pre-WW2 engines. It's pretty generous to say they were designed in the 1960s.
- _yb2s 4y agoContinental sells a range of general aviation engines based on modern Mercedes Benz diesel car engines, initially developed by Thielert as the Centurion. They run on regular Jet-A fuel, and are extremely efficient. https://www.continental.aero/diesel/engines/cd155.aspx https://www.continental.aero/diesel/engines/cd155.aspx https://en.wikipedia.org/wiki/Thielert_Centurion https://en.wikipedia.org/wiki/Thielert_Centurion I think these, combined with biofuel based Jet-A are a good solution to this problem, as electric tech is a long ways from having the range needed. Maybe someone who knows more could chime in why these haven't already completely replaced the ancient air cooled leaded gas motors? My guess is that they're very expensive...
- bluGill 4y agoYou need to get the whole airframe certified to change the engine. If the airplane hasn't been in production for 40 years+ who will pay for that? Does the engineering data needed to start that process even exist anymore?
- _yb2s 4y agoInterestingly, I found that the airplane in question here, the Cessna 172 was actually sold with the Thielert / Continental diesel, but ended up cancelling it because they were so much more expensive than the gasoline models that nobody bought them: https://en.wikipedia.org/wiki/Cessna_172#Special_versions https://en.wikipedia.org/wiki/Cessna_172#Special_versions
- jabl 4y agoI think this is the $100000 conversion alluded to in the article. Not sure what makes it cost that much. Maybe the same thing that seems to have caused GA to stagnate, very small volumes combined with high certification costs. (There's also a company called Austro engines that makes aero diesel engines, AFAIU even based on the same MB car engines Continental/Thielert uses. I think Austro is a subsidiary or spinoff of Diamond, so that's where you see these engines used.)
- _yb2s 4y ago
- jabl 4y agoI think if you want to see 'modern' gasoline powered piston aviation engines, you have to look elsewhere than Lycoming or Continental. ULpower and Rotax make fuel injected aero engines with FADEC. I think Rotax has even certified some of their models.
- Zak 4y agoThe efficiency difference isn't as much as you might think. Car engines today are much more efficient than they were 50-70 years ago, but that's because the difference between maximum power and cruise power for a car ranges from about 5x to 20x. Much of the efficiency gains come from devising ways to deliver short bursts of power from a small engine, such as variable valve lift and turbocharging. General aviation aircraft cruise at about 75% power. There's much less to be gained by optimizing the engine to run efficiently at 10%, and running a small engine at high RPM and high boost continuously is a recipe for frequent service intervals. That's ignoring improvements to transmissions, tires, and aerodynamics in cars that aren't relevant to planes. There's certainly room for improvement, but not to the dramatic degree we've seen with cars.
- jabl 4y ago> The efficiency difference isn't as much as you might think. True, the BSFC numbers of these old school aero engines aren't that bad, actually. > General aviation aircraft cruise at about 75% power. There's much less to be gained by optimizing the engine to run efficiently at 10% I think the real advantage isn't a small efficiency gain in optimal conditions, but rather that with a modern FADEC there's less pilot workload, with a single lever for selecting the thrust the pilot wants, and the electronics takes care of selecting the optimal parameters (throttle position, amount of fuel, ignition timing etc.) for that thrust setting, taking into account input from a number of sensors (temperatures, pressure, etc.). And all those sensors provide data that can be logged and help with planning maintenance before something goes pear-shaped up in the air. > running a small engine at high RPM and high boost continuously is a recipe for frequent service intervals. The Rotax aero engines rev to a max of almost 6000 rpm, cruise is ~5000 rpm, and they have a normal(?) TBO of 2000 hours, including the turbocharged 914. (The turbocharged 915iS has a TBO of 1200 hours, but I suspect it's due to the engine being relatively new, probably the interval will be extended when more experience has been gained?). Of course, these engines are designed for that from the ground up, not saying you could take a random car engine off the street and run it at 5000 rpm for 2000 hours.