# Rear Bear Vs. The Russian Bear

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by pie_row, Dec 2, 2009.

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1. Jan 15, 2010

### Dana

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As did many of us... at least I did! We made pipe bombs out of match heads and set 'em off way out in the woods too.... just good clean American fun.

Nowadays if a kid even mentions something like that the school gets locked down, police called, parents called, kids sent home, and once the Homeland Security goons determine he just might not have been serious, the shrinks have at him to "cure" him of his evil deviant thoughts. Ain't political correctness wonderful?

Be glad you don't live in Hawaii... they shut down general aviation across the whole state when he went there on vacation.

-Dana

As I learn the innermost secrets of the people around me, they reward me in many ways to keep me quiet.

2. Jan 15, 2010

### Topaz

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Yeah, don't even get me started. Here in the People's Republik of Kalifornia, you have to have a permit from the local fire authorities to fly model rockets of any size - even a kid flying a 1/2A motor has to call the fire department out to the flying field to have them "inspect" his rocket and launch equipment before every day's launch. How many times do you think the fire department is actually going to come out and do that? They have better things to do. So the kid ends up being limited to flying with the big organizations once or twice a year at their meets out in the desert - an hour's drive for the parents, who may or may not be involved in the hobby. Rocket clubs at schools are a thing of the past. The school won't allow them because of "the potential liability."

This is assuming said kid could even find a field where he could fly in the first place. Every park or schoolyard here is posted for no operation of anything with a motor of any kind, and most specifically spell out model cars and "anything that flies in the air". All the "open fields" are posted "private property, no trespassing", because the lawyers in this state have made a pasttime of suing landowners when somebody gets so much as a splinter on their property.

And then we all wonder why kids just want to stay indoors and play video games, and develop no interest in math or science... Grrrr.... :roll:

3. Jan 15, 2010

### bmcj

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You jest, yet you raise a very valid point.

4. Jan 15, 2010

### pie_row

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In 1995 (Or there about) Tom Clancy wrote a book that had someone crashing an airliner into The US capital building. In 2001 they did it. Some thoughts are best left un-thought. Some words are best left unsaid. You just don't go there.
9/11/2001 is still to painful.
With a single stage of compression you are going to have less than a 4:1 pressure ratio the theoretical limit is 24%Te for a 4:1 PR. With an 80% E compressor and a 80% E turbine that works out to a 15.36% Te for the cycle. 1lb/hp/hr fuel consumption. Give or take a bit.
ya stow and go is the only way to go.
Cheap CNC is my dream. Getting the compressor E up is what is limiting the output of those small engines.
Here is an idea about tort reform. After everything is done asses the amount of responsibility of the parties involved. The responsible parties (and their lawyers) have to pay the non-responsible parties the damages. So if you steal someone's car get hurt and sue the owner of the car for the damages (to you) then you have to pay them for the amount of the injuries to you. Well your lawyer will at any rate. Split 50-50 and no one gets any money. If they hurt you and they were responsible then you get payed. If they hurt you and you were responsible then you pay them. No more deep pockets.
You said it. We have protected our selves so well that we have stopped living.

5. Jan 15, 2010

### Dana

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On one of the earlyl versions of MS Flight Simulator (I forget the version, but the copy I had was CGA graphics running on a 286 DOS computer), the default situation when you started the program was flying over the Twin Towers on climbout. Natually, the first thing I tried to do was a barrel roll between the towers (if you missed, it just got dark as you passed through the building). I've long suspected that's where the terrorists got their idea from.

-Dana

New Yorkers like to boast that if you can survive in New York, you can survive anywhere. But if you can survive anywhere, why live in New York?

6. Jan 15, 2010

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Which is nonsense.
At least a couple of hundred Hollywood movies and several series like "24" give dozens of ideas each of how to commit effective terrorism. Maybe shut them up too, including your economy?

I have the digital version of "Mein Kampf". Block me from this forum. Shoot me when in sight!

How about forbidding to print or possess the bible? The Bible, Torah and Koran all mention that you have to slaughter non-believers. Burn all those books, track down their owners and put all people who possess one in prison!

I hope you got the point

Because some people got killed? Get over it and stop whining...
Well, I should have made my point clearer, by using CNC I finally see an opportunity to make one axle with several stages relatively affordable. So in fact we more or less agree

Do you guys think the very reason America has such an incredible/horrible liability system is (partly) caused by the way lawyers get paid?
In Europe most countries forbid such a way of payment for a lawyer and though I've always seen it as an interesting system I've heard a couple of people using the above argument.

7. Jan 15, 2010

### Mac790

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This thread is really amazing now we have discussion about politics mixed with religion, what's next? I'll have some ideas but....

Seb

8. Jan 16, 2010

### bmcj

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Maybe if we retitled it "THREAD DRIFT", it would finally stay true to its name. :gig:

9. Jan 16, 2010

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Well, the timeline is a bit distractive, we started in the cold war, went to diesels (21st century), then back to hitler (1930's) and the U2 (1950's) and now we're talking about CNC'ed turbines (21st century).

How about a realistic time machine, I'm sure we can think of a light weight solution to that too onder:

10. Jan 16, 2010

### Autodidact

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Autoreply, America and Americans are no different than any other place or people. We were blessed with enormous resources and our Founders were intelligent and innovative people. Also, it takes a fair amount of resoucefullness to immigrate to America from other places, so we tend to get the best people from other places as well (not a "strict" rule, though). This has made us a very powerful country. But still, were just ordinary people. A lot of what seems like arrogance to Europeans may easily be bravado or "whistling past the graveyard" in attempt to shore up our own confidence (might even try a bit of "dutch courage" now and then ). No one likes to be attacked, and any warrior thats been blooded will tell you that anyone who says they are not afraid of violence is either ignorant or a liar (PTSD, anyone? And didn't the Spartans used to wear diapers?).
Actually it may be good to talk about it, get it out into the open and deduce what is possible so that it can be prepared for. I wasn't so serious as I was commiserating with others who are so tired of terrorism. And please don't put the blame all upon America, we're all at fault here; Europe did its share of empire building, you know.

Last edited: Jan 16, 2010
11. Jan 16, 2010

### pie_row

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Would you please tell that to the department of homeland security. They are reading my emails.
We (The US) are in the process of shutting down our economy as it costs too much money to make stuff in the US and so little to do it in China.
Does bad taste mean anything to you? There are places for The Bible Etc. and there are places to talk about terrorism as well, please not here?
More or less. You need to raise the efficiency of the compressor stages in order to effectively raise the pressure ratio. Two stages you get this. 0.8*0.8=0.64 E 0.9*0.9=0.81 In order to make a two stage or more compressor effective you need to make the E of each stage higher. Why do I want a two stage compressor for my engines? This chart should show why.

It shows a flat torque curve from 9,200rpm to 9,700rpm That is a very wide power band!!!! Now at 7,000rpm it is showing 1.71 bar boost. With a 1.8:1 PR turbo (using 1980's tech) it is possible to run full boost with a 3:5 ratio in rpm. From 6,000 to 10,000rpm or with my old Audi 5000 T from 3,000 rpm to 5,000rpm. So 1.8*1.8=3.24 you would get a 3,000 or 4,000 rpm power band. In a race car that would be a decisive edge.

From here for the chart http://www.gurneyflap.com/bmwturbof1engine.html

12. Jan 25, 2010

### macdonca

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What kind of prop reduction unit are you going to use on a motor that is turning 10k rpms? Thats like a 5:1 reduction to get the prop to 2k RPMS. are these even in production?

13. Jan 25, 2010

### Starman

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Please, don't concern yourself with reality, at least not on this thread, were just talkin' theoretical BS here.

Like, you know, you could use a triple turbo 200cc engine to put out 300hp at 20,000rpm at 80,000 feet, and use the steam from the water to drive a steam turbine, which also has a turbo, and the steam turbine drives another compressor so you can go to 100,000 feet, where the air is so thin that you can go mach 2.818181 with a propeller - as long as it's a pusher. A tractor simply will not work under these conditions! The best shape for it is circular so it looks like a UFO, and you can have solid rocket assisted take off too, and it will only weight 283.556 pounds! You might need to hire a refueling plane, but where could you stick the refueling probe?

14. Jan 26, 2010

### macdonca

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If your going to quote HP numbers why stop at 1400? Engine builders are getting 7-10k HP out of top fuel cars.

Simply put, the auto conversions you are contemplating are not practical for aero use. If they were, someone would have already done it, a long, long, time ago.

My apologies if this was already discussed in the prior 30 pages, but you are going to have a problem with wieght. The airframe you would have to build to accomodate the duct work, hoses, proper cooling, radiators, water tank, etc etc will negate any benefit you gain from the added power of the motor. Now the airframe needs to be solid enough to handle 800hp. Ill give you a hint, a midget mustang, or anything of similar size, is not.

another thing to remember there are a lot of low performance pilots out there that meet there demise attempting high performance homebuilt aero projects. Think about it.

15. Jan 26, 2010

### pie_row

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The engine that has my attention altho it is not rated for continuous power is the TAG Porsche F1 turbo engine. It made 950 hp out of 1.5 L with something like aircraft reliability. (They never broke one in competition.)
The application is Reno air racing.
There is a difference between size and strength. The midget mustang is about the correct size but it would have to be far more massive to handle the power.

16. Jan 26, 2010

### macdonca

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Not going to work in an airplane.

Im assuming you have no race pilot experience.

Exactly how many planes have you built?

When you stop thinking about this one and start doing (big difference between thinking and doing) let us know. Id love to be proven wrong.

17. Jan 26, 2010

### pie_row

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I'm working getting the money. best guess on when is by Novmber maybe. It may be two years.

The porsche wont work it is not built to cool 950hp continuous out put. I'm going to build one to cool A LOT OF POWER.

18. Jan 26, 2010

### macdonca

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Best of luck to you.

19. Jan 29, 2010

### pie_row

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I am more interested in engines than airplanes. I made a pic of the engine I wanted to built in Nov. of 2008. The pic has been revised a bit but I've been doing research for a year on the project. In getting the money I hit a snag (The recession) So I got a bit distracted and have been working on a cure for the recession. I've got a plan for getting rid of the recession. Cure is the word that I'd be using.

20. Jan 29, 2010

### macdonca

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If $is a concern for you then your project is never going to get off the ground, literally. Just on your basic assumptions, your engine will need to run consitantly in the 9,000-10,000k RPM range consistantly to maintian proper propeller effieciency. Your talking abount full complete overhauls every hour of flight time. Its not a practical vision by any means but if you have$ to burn by all means. I suppose you would need at lease \$2 million to burn on this to get a prototype in the air. And a considerable amount more to keep it going.....