Best Standard Airplane Engines?

Whether or not any of today's crop of piston engines is "perfect" is open to debate. Except for the ill fated Continental Tiara there hasn't been a new engine in at least 3 or 4 decades.

All are air cooled, a legacy idea from the 40's when people were convinced that liquid cooling was subject to problems. That air cooling may be more reliable may add some comfort but there is no question in my mind that air cooling costs us in thermal efficiency (higher SFC) and needs extra points in octane to ward off detonation.

I absolutely love the sounds of a big recip but in a world caught up in the economics and wars over oil, they are boat anchors nevertheless.

Turbines do nothing for me.

I suspect the piston engine is destined to become extinct a lot sooner than any of us anticipated.

L.J.

Hello Jaguar,

You state: "I suspect the piston engine is destined to become extinct a lot sooner than any of us anticipated."

Do you know some secret "other" mechanical power generating device we all don't know of?

Or, what makes you think that way?

I rather trust the statement of Dieselphil:

"And you can't beat the compression ignition cycle!"

Regards

For constant speed/power applications like aircraft, a turbine is far superior to any recip in "most" commercial applications.

If nothing else the maintenance cycles are a fraction of the cost of recips.

Hooker

Hello Hooker,

That is correct, I agree with you. It specifically applies for high altitude and continuous steady speed, best at full power.

Recreational sport flying however has no such criteria. Another good reason jet engines are not used in small aircraft are the cost for the turbine itself as well as the high amount of fuel they burn. In other words, the efficiency is not very high, especially at low altitude and at part load operation.

The comparison of maintenance costs is something I don't know, simply because there are no figures for small Turbines in the 100 to 300 hp range available as these are not in use. Small helicopters start at about 500 Hp. However, their maintenance costs are not low in comparison to a piston engine.

Although this option exists, it is not very viable.

What we should have is a piston engine (not necessarily a recip) that has a TBO of perhaps 3000 hr. What I mean to say is low overhaul costs.

Another possibility to some extend is the Wankel Rotary. It has a high endurance load capacity, burns a bit more fuel then a recip but not too much more. Some people argue that it is equal.

I still would prefer something round, not a waste-lake eight figure.

I think the Rotax 914 is a good example of what is slowly but surley the next generation of engines. liquid cooled with turbo in a light weight package though personally i think the fuel delvery system should be scrapped. I worked on them in the steme motor gliders, all the preditors use them as well.

Hi guys,

apart from the fact that there will never be a "perfect" engine the ones you mention are pretty good.

The still around after nearly 70 years flat 4 & 6 cylinder Lycomings and Continentals have remained "fit for purpose" for longer than almost any other mechanical device that I've come across, and so must be placed right up there. However there is a new crop of aero engines gradually coming into the marketplace so those old guys may not be cock-of-the-roost for too much longer.

On liquid v air cooling - it does seem a bit crazy to drag heavy coolant and systems into the sky, so if air cooling can be made to work it's obviously preferable. Failure modes make it much better to keep it simple whenever possible. Can you imagine air cooling a submarine engine!

Internal combustion engines aren't likely to disappear as long as they remain simple, reliable and efficient - there is no other technology to replace what they do. Sure there will be many new technologies introduced for heating homes, generating electricity and for larger uses but to provide mechanical work at a mobile location they are, and will likely remain, the best option for a long time to come.

And you can't beat the compression ignition cycle!

Happy replying ...... DP

Does the Rolls Royce Merlin not fall into the same category?

It powered the Spitfire, Hurricane, Mustang etc

I have only had experience with the Wright R1820-82A of which there were two on the Grumman S2-E Tracker.

Of the three years as a flight deck trouble shooter, we had no engine failures (other than one engine that had a blocked lower cylinder drain, causing a jug to rip off on start) for a squadron of about ten aircraft.

These planes flew 8 hour missions over mostly the North Atlantic, about 300 ft off the water, sometimes at night.

If you have ever seen a cutaway display of one of these radials, you would have to agree that they are works of art.

For light general aviation, my hats off to Continental and Lycoming : Reliability is all there and, in my opinion, that remains the foremost criteria. The various 4 strokes Rotax may be wonderfull jewells but are commercialized as such price wise. Additionaly, my understanding is that the TBO do not yet compare and even if they should one day, they remain more fragile items - to be or not to be a jewell...

I would not be surprised that much if, within the next 20 years, batteries would evolve sufficiently to make the electric motor the best choice for some light aviation applications (going further than assisted hang/para gliding).

http://www.youtube.com/watch?v=7Dr4FJsEjzU

I like em.....

Porsche had one flying around a while back. Lightweight, air cooled and powerfull. Don't know what demise was.

Some air-cooled VW engines still flying...some cut in half and converted to two stroke.

The Porsch engine (forgotten its designation) was basically too sophisticated and expensive for the marketplace - no point trying to sell something into a market that doesn't want it. I think there are still a few airframes with them attached preventing accidental lift-off in high winds.

There are many air-cooled VW derived engines flying in Europe, where there are also quite a few 2-strokes of various design, in flying bedsteads, microlights etc especially.

None of these can be regarded as great engine designs though. I am in 2 minds about the Merlin/Griffon - they certainly sound lovely and did a great job at the time but are not really the robust fit 'n forget devices that would tempt me into labelling them "best".

Any pilot will tell you that the "best" engine is one that is v. boring - it just goes on and on and on and on making that noise whatever the conditions, weather, attitude, altitude and the stupid pilot does to it.

keep them comments coming!

Ya.....with the Porsche the problem was servicing. Didn't exactly lend itself to field stripping.

Lycoming good that way. Easy to work on.

'Good' also depends on areas where one flies ie arctic, desert, jungle. Arctic definately has its parametres.

An engine I forgot to mention consists of an elastomeric loop with a fixed anchor and the output end attached to the prop shaft-very reliable!

Also, lets not forget the Corvair engine, originally intended for aviation.

What about the one the one made of muscle fiber, supported by calcium struts, often used to propel craft composed of folded panels of compressed wood-pulp fiber?

Here's another one: Flat four two stroke made by West Bend for target drones.

A guy put one on a motorcycle frame and set some land speed records.

Consider the ak47, ultra reliable, servicable by just about anyone.....

There is probably a lycoming, continental, that's been knocked off by russian designers, but been ruggidized for bumpy, dusty airstrips....& able to be serviced by any yahoo with a cresent wrench........

I used to work for a crop duster, who had these polish planes with radial engines, more powerful than the pratt & whitney equivelant, required less service, been a bunch of years, can't remember more details... ran on pump gas too

Here's a Russian AN 2 workhorse. Possibly the only dual wing a/c built today. Not bad to fly and remarkably stable. It had the only engine I saw start at -40'c without having to warm up the oil. Engine comes with a decompression valve.

Here's what I was talking about

http://en.wikipedia.org/wiki/PZL-Mielec_M-18_Dromader

& here's a very common US built biplane

http://en.wikipedia.org/wiki/Grumman_Ag_Cat, most commonly fitted with a pratt & witney radial, which should be in the running for best powerplant

Those are tough planes. I've seen a few of the Polish ones in Ontario.

http://www.vikingair.com/

These guys got the blueprints for the Twin Otter and Beaver before Bombardier had a chance to destroy them. Based in Victoria BC.

Just wanted contributors to this thread to know I have read the contributions so far. I am reminded of an earlier question I asked that seemed to suggest the 172 Cessna as the best commonly available plane. Damn I like to sit on a wing instead of hang from it. Anyway Cirrus is supposed to be a nice machine to fly around in and came from experimental. Further it seems there are about three engines to design around, maybe four, for light aircraft at least. Finalized list, with up and comers would be fun to close with. Someone with an Aircraft and Powerplant license to contribute for that close would be a valued critic.

The thing is, when you "hang" on a wing, Cessna 172, you have a good view down to the ground.

If you "sit" on a wing, so to speak, the view down which you need most, is severely restricted.

Greetings

Have you tried the FAA aircraft registry database?

What goes down least is probably best.

A "view down" and "going down" are two different things. Won't you agree? :)

But are right, that list is too big for what it should be, or could be.

"Best" is always a tough one - I spent years counting on the old turbine installed in the P-3 and C-130.

Reliable, tough, dependable.

But hungry! Turboprop is a great way to go relatively slow with lots of power on demand.

So as always, the question of best has to be put within context. The currently available Lycoming, PW, Continental, etc. are durable, reliable, and dependable. Also relatively underpowered, over-simplified, under-optimized.

And staggeringly expensive.

The EAA (Experimental Aircraft Association) membership have been doing some stunning work over the last decade moving auto engines into aircraft for many reasons, one of the strongest is the removal of a zero from the price.

Probably one my favorites for power vs weight is the old Mazda 3B rotary with turbo charging.

If you want to put your hands on some 28 cylinder engines and others, the air museum a few miles south of Tillimook Oregon has quite a few on display in an old world war 2 blimp hanger. Four banks of seven radial cylinders is very, very impressive close up.

How about the WWII Packard V12? It powered both aircraft and water vehicles.

Was that the engines they put in PT boats, 4 of them?

Dunno. They supposedly left the engine slightly unbalanced, otherwise harmonic vibration would shake it apart. I think the heads were disposable.

Gentlemen, gentlemen

The question was best STANDARD airplane engine.

As much as I may admire the engines cited here, such sterling examples as the Merlin, the Wasp; almost none of these examples would do today as an aircraft engine.

The standard rotary used nearly as much oil as fuel.

As we squeezed more and more power out of what we had to work with, reliability through the war continued to decrease; with some engines in the neighborhood of less than 1,000 hours of service life, and some major service required in as little 100 hours.

Probably my favorite aircraft, with the Wright engine. The Staggerwing:

http://en.wikipedia.org/wiki/Staggerwing#Variants_and_design_stages

Ah Bricktop,

Between the Power wagon and the Staggerwing I want to marry you and I really like your taste.

I'm into steady and reliable myself.

That would be the contractor team having finished loading up

I'd like one of these too:

The Hemi jeep conversion from AEV.

http://jalopnik.com/5068365/aev-hemi+powered-jeep-wrangler-first-drive

Something like this would be a whole lota fun:

I really like bi-planes. I got to fly a Stearman a few times:

not in military colors though.