What's going to happen in the future

[jarrodeu]

Re: What's going to happen in the future

if anyone is interested in reading the full Air&Space 6-page article about the evolution of the Thunder Engine/Orenda V-8 conversion for aviation use, please mention so and I'll scan and post them in this thread (if it's OK with Wayne). It's quite informative to those interested in automotive-to-aviation powerplant conversions and problems.

AirDOGGe, I would be interested in the rest of the article!

Thanks,
Jarrod

[shadow]

Re: What's going to happen in the future

But I don't believe gear drives reduce these loads in any sufficent quanity to solve the damage problems. Merlins use reduction gears too, and their crankshafts still experience such vibrations (but merlins went through years of expensive development, testing and redesigns to help them withstand these aviation-related problems).

And you can't compare boats directly to aircraft. The large diameter propellers on aircraft produce rotational vibrations that are far different than those of small diameter, high RPM boat screws.

First off, excellent post. That one page illustrates perfectly the issues with automotive conversions.

The Air & Space article uses the term Torsional Vibration, while the website I linked to uses the term Torsional Excitation. The Air & Space article refers to power pulse diagrams which actually exist on the link I posted. If you want to know more about the problem follow the link and you will develop a greater understanding of the issues involved than you could probably ever care to (maybe 100pages worth). It's almost like a book on the issue, it covers so much information. Even then it's still only an abbreviated source. The engineering literature behind these issues would span volumes.

EPI have solved the problem and have a PSRU that should be nearing testing now that in a certain configuration can handle 1600ftlbs of torque, will weigh around 100lbs, will have jet-like smoothness at the prop, and cost around $10k. This is a design they are testing now.

I am certain that these guys can come up with a PSRU to handle 3000-4000ftlbs of torque. It might cost $50k, it might weigh 250lbs, but it will be something that is produced today, and supported by the manufacturer (read engineers experienced in this area) when it breaks. AND these breaks will lead to refinements and modifications of their product.

Be wary, all this information I have gathered from the site (http://www.epi-eng.com/GBX_TOC.htm), and from other articles on the internet which are dumbed down engineering stuff (http://www.interfaceforce.com/suppor...excitation%22).

In short, the issues are known and measured. Solutions exist, have been tested, and are in service today. All we need is a bigger version that can handle more power.

Making new powertrain systems for unlimiteds class racers sound like $10M projects with scads of engineers, development cycles, and thousands of hours torture-testing is fallacious. Are the race engines used today subjected to such things? No, they are one-offs created by trial and error (Trial and error accumulated over many years of experience working with them).

The engine exists, the PSRU is waiting for someone to order it. What is needed now is someone with some capital to be sure, but with the motivation to seek out these components and bring them together. It will take time, but what doesn't?

From what I've been able to find out: Cost of the 904ci Schubeck engine $85,000. It weighs about the same as a BBC.

In the car industry, there will come a time when the price of gas gets to the point where alternative fuels become economically feasible. I suggest the same will happen in Unlimited Air Racing. There will come a time when alternative engines will be cheaper than the engines we have today.

[Bill Marsh]

Re: What's going to happen in the future

The auto v8 myth never dies.... GREAT energy and INTEREST tho !!!!!

I know its old info, but the basic problem still is the same, it Odena couldnt make it happen with a rat / chev / gm starting point..... finally making everything from scratch and with lots of willing buck$$$ (to a point where investors bailed? (i guess))

Sooo, How can a handfull of Sport racers manage to do better..... and where will the money come from.

Seems the ga powerplants will do fine ..... going way past the 400 mark.


BM

[AirDOGGe]

Re: What's going to happen in the future

AirDOGGe, I would be interested in the rest of the article!

Thanks,
Jarrod

I'll try to get it scanned and posted later today.

[Fence Sence]

Re: What's going to happen in the future

Just curious as to why noone has brought up the Allison issue. With a modern airframe and a properly tuned Allison, couldn't a reasonably priced Unlimited be produced that could seriously compete?

[jarrodeu]

Re: What's going to happen in the future

Just curious as to why noone has brought up the Allison issue. With a modern airframe and a properly tuned Allison, couldn't a reasonably priced Unlimited be produced that could seriously compete?

Like the grand 51?

http://cameronaircraft.com/team51/team51.htm

Jarrod

[Fence Sence]

Re: What's going to happen in the future

Yeah, like that one. We need Air Race Addict to give us an update on that thing. Last I talked to him, he said they were skinning parts. That project, at least to me (I know, BFD), seems like the future of the Unlimited class. With all this talk of new power plants, I tought it approprate to bring those guys up.

[Race5]

Re: What's going to happen in the future

FYI, Orenda is alive and well. It was sold to a group of investors and is moving from Canada to Texas, about two miles from my house. They will be shipping engines again by Dec. Their main focus now is a dedicated aircraft engine, not a conversion. However the auto conversion problems are being worked on for them by Franz Weis. (sp) If you are not familiar with that name, he is one of the major brains behind what was Ilmor Mercedes in Indy cars and F1. I know, I know, cars and airplanes are different, but he has the knowledge, people, facilities, and $$$$$$$ to get it figured out.

[AirDOGGe]

Re: What's going to happen in the future

They use to have the V8 mentioned on their website, but don't see it there anymore. They seem to be concentrating on turbines, which is what they started with.

This bit of text I ran across seems to verify what you said about trying to restart the line...

In the late 1970s, race car driver Lee Muir started a project to adapt the 8-cylinder aluminum-block Chevrolet CanAm engine for aviation use as Thunder Engine.

In 1994 Orenda purchased the design, completing the certification process in 1998, and putting it on the market as the Orenda OE600. They marketed it primarily as a replacement for 600 hp turboprops, notably the Pratt & Whitney PT-6. The engine offered better altitude performance due to its twin turbochargers, as well as somewhat better fuel economy.

They also set up a conversion facility as Orenda Recip at the former CFS Debert in Debert, Nova Scotia, and started certifying conversions for various popular aircraft, starting with the DHC-2 Beaver, with plans to offer similar conversions for the DHC-6 Twin Otter, King Air and various crop dusters powered by the Wright R-1830 or eastern-block designs of similar power.

Magellan (who owns Orenda) dropped the project in the early 2000's, reportedly after $100 million had been invested in development. There is an effort underway to restart production in Texas, but it is unclear if this is continuing.

In 2002 the engine sold for $150,000 USD, instaled and ready to fly.

.

[Danimal1]

Re: What's going to happen in the future

So, the subdivision investors have gone to Montana or LA
(Lower Alabama) to seek their property and RARA has become a
"FOR PROFIT" agency huh?

[Apteryx]

Re: What's going to happen in the future

Just curious as to why noone has brought up the Allison issue. With a modern airframe and a properly tuned Allison, couldn't a reasonably priced Unlimited be produced that could seriously compete?

Cameron Murdo and Dan Mortensen hope to find out.
(Carbon-fiber full scale 'stang, in case you didn't know).

Did anyone see a Team-51 display?
(They were going to sell t-shirts and hand out info).

Paul

[Race5]

Re: What's going to happen in the future

They seem to be concentrating on turbines, which is what they started with.

.

Actually, they have a piston design that is intended to REPLACE the turbines in some models. Mostly AG stuff. Once they get a little more set up, I am going to run over there and see what it is all about. I noticed them putting stuff in the "show room" in the building today.

[AirDOGGe]

Re: What's going to happen in the future

OK, here's the full 8 page article (not 6 page, my mistake), plus a second sidebar about automotive-powered aircraft of the past. Enjoy.

Article title: POWER STRUGGLE: Wy car engines can't fly
Article source: Air & Space Smithsonian magazine, Jan. 1997
Author: Don Sherman

[jarrodeu]

Re: What's going to happen in the future

Wonderful! Thank you very much!

Jarrod

[AirDOGGe]

Re: What's going to happen in the future

Actually, they have a piston design that is intended to REPLACE the turbines in some models. Mostly AG stuff. Once they get a little more set up, I am going to run over there and see what it is all about. I noticed them putting stuff in the "show room" in the building today.

That's the same motor as in the article, which was intended as a PT6 substitute for several aircraft. It's a "spin-off" division solely for the V8 known as Orenda Recip. That's the line they're trying to restart in texas.

They have (had) packages for AG planes and others like the King Air and Otter. The biggest advantage of the V8 is a much cheaper rebuild cost over the turboprops.

Orenda (the main component manufacturing division that is now named Magellan Repair, Overhaul & Industrial ) is still about turbines and is still located up north. Here's their website:

home page:

http://www.magellanroi.com/index.html

component manufacturing division:

http://www.orenda.com/

.