Diesel aviation engines

[310]

sstearns2,
I mentioned the IO-470D, not some of the carb version of lower compression ratio, .42 or .43 for the IO-470D.(260hp)

 

[MSNFlier]

what about small turboprops??

Just a thought (and I am BY NO MEANS an engineer of any kind): with the advent of jet engines which weigh just 85 pounds but develop 770 lbs of thrust like the Williams EJ-22 developed for the Eclipse (and yes, I know it is having some teething pains), is there a place for a small turboprop engine dervied from something like that, instead of a diesel, or no?

I would think that the initial weight issues are addressed because the EJ-22 engine itself is so light, but would the other mechanical requirements to make it into a turboprop make it so heavy or complex as to be impractical?

As I said earlier, I don't know much about the engineering side of making something like that happen, but I'm curious whether others with more knowledge about these kinds of issues might have some thoughts?

Interesting thread.

 

[CRJ200FO]

Re: what about small turboprops??

Just a thought (and I am BY NO MEANS an engineer of any kind): with the advent of jet engines which weigh just 85 pounds but develop 770 lbs of thrust like the Williams EJ-22 developed for the Eclipse (and yes, I know it is having some teething pains), is there a place for a small turboprop engine dervied from something like that, instead of a diesel, or no?

I would think that the initial weight issues are addressed because the EJ-22 engine itself is so light, but would the other mechanical requirements to make it into a turboprop make it so heavy or complex as to be impractical?

As I said earlier, I don't know much about the engineering side of making something like that happen, but I'm curious whether others with more knowledge about these kinds of issues might have some thoughts?

Interesting thread.

Actually, the main problem with a turbine engine on a light plane isn't the weight, it's the cost. Turbine engines are extremely higher in price than a piston engine, even if it is diesel. There are people that take their light singles and pay to have turboprop conversions done, but they usually end up spending half a million to have it done. Even the Eclipse, which is supposedly going to revolutionize light aircraft, costs in the neighborhood of $900k. For your average cessna or piper owner, turbine will not be a possibility for many years to come. The engine costs more than their entire aircraft costs.

 

[cvsfly]

A couple of years ago at the NBAA convention Williams had a display of all their engines including an experimental prototype turbo-prop engine. Measured about 3' long by 8" round and weighed 80 lbs. I think the we will see a reasonable/affordable turbine engine in the near future.

 

[DIRT]

Avgas

I guess when they stop selling Avgas I'll just get a really big rubber band for my C150.........

 

[310]

correction to previous post

According to zoche's and sma's webites the sfc of their engines is better even than I posted before. At cruise power zoche claims a sfc of .346 lbs per hour/horsepower and sma claims 215 gr/kwh average which converts to .353 lbs per hour/hp. (1 kwh = 1.341 hp) ( 1 lb is 453.59 grams)

These sfc are not possible in a 100LL as far as I know.

 

[sstearns2]

EJ-22 and zoche engines

Hello all,

The EJ-22 is an interesting engine. Williams developed it beause NASA gave them a tremendous amount of money. They claim a weight of 85 pounds, but they put everything possible under airframe weight. Things like fuel pumps, hyd pumps, stater/gens, etc. As far as efficiency and price are concerned, we'll just have to wait and see. I hope they can make it happen, but I think they told NASA whatever they wanted to hear to keep the cash flowing.

I'm sceptical of Zoche's claims. They've been working on thier engines for many years and have yet to actually sell an engine. Certification seems to always be 'about a year away'. I want to make a webpage about my new tubro-stearns cycle engine that makes 300 HP at 7 gallons/hour and see how many deposits I can get.

Scott