Guardian

Whats the fastest turbine heli ? I might attepmt to break it !!!

BasinBum

My Feedback: (2)

I'll ask Scott at work today if it's true.

jwoolridge

I dont know how many here know this but Hp is only a factor of your torque times rpm. Torque and HP are equall around 5200rpm when u double the rpm to 10400 you double the HP. Now you think about the rpms a turbine turns. It's usually around 150000rpm now you know why they have these huge HP numbers. Horsepower is a uselees number the important number is torque. Wish that engine manufacturers would give out torque numbers because then it be easy to compare the power of one engine to the power of another.

Back to the important stuff now going fast. Glad I'm not the one trying to keep my eyes on a plane going 280mph. I dont know if I could and I got 20/20 vision. Congradulations to all those who can keep up with the planes and have set these records.

James

BasinBum

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Scott said he was clocked at 264mph with a radar gun on a speed pass head high after a race. They can't get that fast during the race because of scrubbing off speed in the turns. He said everybody took a few steps backward when he came by.

erazz

Ahemm... James,

Don't want to knock you but you took one fact waaaay to far.

HP = torque * rpm. That much is true.
HP and torque are NOT equal at 5200 for the simple reason that they are not the same thing! One is the product of another.

You might have meant that HP and torque max out at 5200, that might be true for SOME engines but certainly not for all.

Also, doubling the rpm does not double the hp for the simple reason that torque does not stay constant at different rpm. The torque that our turbines turn is minuscule and is not a real measure of the power of the turbine (actually torque is force per distance while power is measured in watts or hp).

One more thing. There are a couple of ways that you can measure the power of the engine (static, flight etc..). If you look at flight power (thrust * speed) then the power of a turbine actually increases as airspeed increases and THAT causes the huge performance we see in turbines.



One more footnote about fast airplanes. At my university we have a long range program to develop and fly a supersonic rpv. Just so you know, our engines are not capable of taking airplanes to supersonic speeds just because their exhaust velocities are subsonic. Taking such an aircraft to supersonic speed will have to include certain improvements such as an afterburner and variable area nozzle.

Mike James

I am not currently a jet pilot, but I come in peace, my brothers in aviation.

I learned while skydiving, that to convert miles per hour into feet per second, you multiply by 1.466667 (You can "track" in skydiving, at about 180 mph, or 264 feet per second.)

At 300 mph, you are moving a 6-foot-ish object at 440 feet per second. I think a turn at that speed would bend the sticks on your transmitter...

Amazing.

jwoolridge

You are probably totally right I just wrote what someone once told me. He happened to be a car mechanic and I assumed it applied to all things which had torque. Anyway not a huge deal I just wonder what the HP numbers would be if the maximum torque of a turbine was acheived at say 7000rpm so they could be compared to large gas engine for example.
James

grbaker

My Feedback: (29)

erazz
Please keep us posted on the progress of this project. It sounds very interesting.

diceman

My Feedback: (10)

The FAI is the international sanctioning body for all world aviation records. This includes everything from sailplanes to spacecraft. All aspects of R/C are also recognized.

The AMA also list the US / AMA records.

mr_matt

My Feedback: (10)

Once you get into this realm the sky is the limit. THere have been supersonic "rpvs" for probably 50 years.


http://www.vectorsite.net/twuav1.html

mr_matt

My Feedback: (10)

It's do-able......I have done 413 fps, just make sure your eyeglasses are clean and you have been eating your carrots.

erazz

Shhhhhh! The AMA/KGB/Secret police are listning! You get into trouble...


Yup, costs go sky high as well. Our goal is to use off the shelf products as much as possible.


It is and I will. Please remember that this is a long range program meaning a couple of years. It's also subject to the whim of the money holders... I just hope it doesn't get cancelled.

All we have now is an idea for the engine + a vague idea on how we want to do the airframe. We havn't even begun work on control.

seanreit

My Feedback: (60)

FWIW, I heard that a glider in the swiss alps did over 400, I've never thought to myself whether this was fact or fiction, as the person that told me was an experianced modeler. Can anyone offer opinion as to whether or not this could have been achieved? Reason I ask is, based on what I'd heard, I've told a few people that claim from time to time. I was never told "that's impossible" so I just kept on believing it. Has anyone heard of this?

JWN

My Feedback: (42)

Sorry, but this is not correct. The correct equation is:
HP = (torque x rpm)/5252

Because of this, HP and TQ will ALWAYS have the same figure at 5252 RPM. There is no way around this.

John

Mluvara

My Feedback: (10)

304 in a straight line would be very much possible if over a wide area to gain the speed. Like was said, 300cc + a very high pitch prop will gain speed. The Super Corsair that Scott pilots does 240 avg on the course and the pylons are only 1600 ft apart.

mack845

The world speed record is held by Niels Herbrich of Germany flying a slim pink delta equiped with a data log recorder.
The speed in level flight was 576 Km/Hr or 360 mph. The model was powered by a standard Behotec JB130 (28.8lbs thrust)
Go to www.behotec.com and see the JB130 and also have a look at the Galerie, the pink speed model is there.
UK agent for Behotec.
mack 845 @aol.com