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Old Dec 15, 2002, 03:16 PM
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Charlotte, NC
Joined Dec 2002
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hehe

I was thinking the same thing!

I went to their site and all they have posted by the pic is,
Quote:
"This is a "Harrier" AV-8 Jump Jet model being made at the "Fleet Air Museum" in Somerset, England. It will be a technology demonstration exhibit with actual tethered vertical flight demonstrations. It uses 2 Max15-13D motors driving axial flow ducted fans and exhausting through 4 vectorable ducts."
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Old Dec 15, 2002, 10:24 PM
Carbon fiber is our friend
Steve C's Avatar
United States, CA, Lodi
Joined Feb 2001
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Sure doesn't look like enough room for axial flow. There's a possibility that radial fans would work in a similar situation, but I'm not sure how they plan to get air to the rear unit.

I've got ideas for a larger VTOL electric Harrier. I'd go with a large diameter and a geared motor turning the fan 12,000rpm or so. The reaction controls would be powered with a second motor/fan so that the lift fan can have clean ducting and maneuvering doesn't cause a reduction in lift.

Steve C
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Old Dec 15, 2002, 11:25 PM
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Joined Nov 2002
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WOW ! The power unit looks complex, I was thinking of something simple, like four seprate motors. The largest hurtal so far has been to find information on flying models. It helps to know what not to do and to see what has worked for others. I have seen one designer make a power unit that looked just like the real power unit but No footage of if ever working and it was a glow power unit.
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Old Dec 16, 2002, 12:29 AM
Should get a life
Tom Cardiff's Avatar
Muncie,IN USA
Joined Mar 2002
209 Posts
Looks a bit like the thing that popped out of John Hurts stomach in alien.
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Old Dec 16, 2002, 01:18 AM
Carbon fiber is our friend
Steve C's Avatar
United States, CA, Lodi
Joined Feb 2001
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There is one that I know of that is actually built like the real one. Some guy down at MWE showed me pictures of a gas turbofan that he had built. Looked just like the real thing. He had not figured out how to make the rear nozzles move yet, since they change dimension with the heat. I saw video of it running too.

The way I see it, starting with a Dynamax or similar (like the one pictured), is a handicap. That fan was intended for high speed, not high thrust.

Steve C
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Old Dec 16, 2002, 07:48 AM
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Charlotte, NC
Joined Dec 2002
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I'm trying one using 2 fans/motors. I'm working on getting the variable pitch rotors working right, currently the linkage cant support the torque needed if your above half throttle (it flexes). If you throttle down it works just fine (1/2 throttle).

It probably wont work, but what the heck!
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Old Dec 16, 2002, 10:24 AM
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Doc Watson's Avatar
UK
Joined Mar 2000
1,197 Posts
I've got 3 views and X-sections. (I've also got 90% complete drawings for a 1:9th scale GR7 using an OS91VRDF, Viojett fan unit and Weston mini pipe, but with 15% nitro and 100 dB I never built it )

Thrust was always marginal as you loose about 40% thrust due to turning the air through 90 degrees in the nozzles.

It has been done though, Eric Dainty? is the man with a 2 nozzle ic powered harrier.

Thought about doing the replacement of the harrier the F35b??

www.awatson1.fsnet.co.uk

I've been after a VTOL scale machine for years and I'm soooooo close I can taste that burnt out ESC



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Old Dec 16, 2002, 10:48 AM
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Charlotte, NC
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Looks great Doc! You'll have it soon

I would love to increase the scale on my project but unfortunately that would require buying a new truck And the Harrier is a must for me just cause its always fascinated me.

Good luck!
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Old Dec 16, 2002, 02:44 PM
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Doc Watson

Doc, I wondering if I might be able to get a copy of your GR 7 stuff, of course I am will to pay you for your time and shipping cost ?
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Old Dec 16, 2002, 05:26 PM
Carbon fiber is our friend
Steve C's Avatar
United States, CA, Lodi
Joined Feb 2001
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Doc, I know how difficult it can be to stay motivated on a long term project, but I'm sure you're going to make it work. We all wait in anticipation!

Mass flow is what's going to lift these things off the ground and Doc's has x 3! That's why I think a Harrier would be easier if it's bigger. It would take a pretty big fan to equal the lifting power that Doc has.

Steve C
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Old Dec 16, 2002, 05:27 PM
Big gov never Works
St. Martin's Avatar
Skunk Water, Rhode Island
Joined Jul 2002
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Originally posted by Steve C
The way I see it, starting with a Dynamax or similar (like the one pictured), is a handicap. That fan was intended for high speed, not high thrust.
Steve C [/B][/QUOTE]

I agree, I used the hurricane & the dynamax. I also used the Boss 601. This had very high thrust and no faster than my Byrons fan. Used OPS 65. 12-blades.
Don't think this is available anymore, Kress had it last. Believe it was made in England?
Steve
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Old Dec 16, 2002, 09:24 PM
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Aten W Arthog's Avatar
Joined Sep 2002
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I just wanted to suggest that you don't "necessarily" have to cut up a plastic model kit to get your sections.
I have found you can just wrap pieces of heavy-gauge solder wire gainst the model, then pop them off and throw them on the old scanner or zerox. back in the day, I hear tell they used to use wet spaghetti noodles draped over the model and left to dry... they would then pop off leaving perfect former shapes. If I would do this today, I would first spray the model with some nonstick cooking spray to facilitate removal of the somewhat brittle dried "formers".

And serve them with a nice marinara sauce with mushrooms;-)
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Old Dec 16, 2002, 09:29 PM
My cat up close
bipeflyer's Avatar
England
Joined Feb 2001
4,021 Posts
I think the Boss fan was Swedish.

Matt.
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Old Dec 17, 2002, 12:07 PM
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North Germany
Joined Dec 2002
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Hi World

Richard here from North Germany.

I just fell across the Subject here about the harrier, being a harrier freak myself ,I came across (Advanced design). They seem to be building the harrier and want to make into a kit.

(I think itīs odd they are looking for help with funding though!)

They sent me a e-mail because i said wanted one , but it still seems to be in itīs test phase.
Hereīs the address for people to look at the specs...

http://www.excitingrcm.equology.com/html

Looks like i shall have to stick with my cheapy MW54 and Mirage then

With kind regards
Richard.

P.s. I noticed in a few other places in the forum that people wanted help with communicating with German companys. Well if i can help anyone, here i am...
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Old Dec 17, 2002, 12:11 PM
Purple power
gregg f's Avatar
shadow hills,ca
Joined Apr 2000
6,594 Posts
richard: welcome to e zone. there is another thread about that project. interesting reading..............gregg

http://www.rcgroups.com/forums/showt...threadid=76736
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