Extreme Speed Prop Planes Discuss the need for speed with fast prop planes (Screamin Demon, Diamond Dust, Shrikes or any REAL sound breakin'''' plane)

Need Advice on my F-5

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Old 05-30-2009, 10:56 PM
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Steve_S-RCU
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Default Need Advice on my F-5

Hi,

I am almost done building my Bob Campbell T-38 which I kit bashed into a F-5. My question is it too heavy to fly? I found that the nose is very heavy and requires 1 lb and 7 oz of lead in the tail to balance the aircraft. I would like to here from people that are fly prop jets if they think it will fly or if I should make changes. If so what??


Here are the specs:

Wing span 56 inch
Wing area 575 sq inches
Wing loading ~ 48oz/sq ft (I think the plane will weigh ~11.5 pounds)
Engine Magnum 0.52
Prop APC 10x7

Thank Steve
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Old 05-31-2009, 12:19 AM
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Default RE: Need Advice on my F-5

Sounds heavy, for that size model, models in that size catergory generally weigh about 6-8Lbs I think, you may need a lot of runway.
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Old 06-08-2009, 01:32 PM
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Default RE: Need Advice on my F-5

Hello there

You will need a Bigger Eng for that .
Webra .60 rear exh. just make it flyable.
You need ,77 to .91 to fly that bird.

Have Pic in my Gallery This one has a Rossie 81 gets this plane going'
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Old 06-08-2009, 01:57 PM
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Default RE: Need Advice on my F-5

Hi!
Sorry! But it 's too heavy! Perhaps it will fly if you use a tuned pipe but not otherwise.
Lighten it and it will fly good!
Never ever put lead in a plane to balance it! Move or remove things to achieve proper Cof G!
Aim for a weight around 3,5-4kg!
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Old 06-08-2009, 10:54 PM
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Default RE: Need Advice on my F-5

What would you do at this point to balance an under powered plane that is ALREADY nose heavy and seriously overweight [with no ballast included]?
I think it is a very pretty prop-jet and it should be hung from a very select spot in the workshop.
I would not waste my time trying to fly it. There's too many other good planes out there to swap your gear into and have some real fun with.
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Old 06-08-2009, 11:43 PM
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Steve_S-RCU
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Default RE: Need Advice on my F-5

Hi All,

Thanks for the input.

Angelrcdesign,

Your T-38 look to be about the same size as my F-5. What is its weight? What is it construction? Where is your CG? How did you get it to balance? Did you do it with only need equipment?

Thank

Steve
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Old 06-09-2009, 01:17 PM
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Default RE: Need Advice on my F-5

you guys have it all wrong lol take the weight out of the back and then add a jett 60 LX to the front and the rear. This will take care of the power and get rid of useless weight.
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Old 06-09-2009, 03:47 PM
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The weight is (9) Light weight  balsa in the front but its a little soft, heavy stuff from the C/G back. and faom wing tail and rudder. I also add 3 inch
to the tail and took off 2 inch in the front. And the C/G was 3 inch back from the leadnig edge. ALL THE EQUIPMENT IS IN THE REAR and the fuel tank is on the C/G.   

I would like to see that done.  60 in the front and back.

I'am still working on my proto type for the .50 size.
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Old 06-09-2009, 10:47 PM
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Steve_S-RCU
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Default RE: Need Advice on my F-5

Hi Angelrcdesign,

Thanks for the info. One more question, you said all the equipment is in the back does that include the aileron servo and flap servo?
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Old 06-10-2009, 12:35 AM
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Default RE: Need Advice on my F-5

The servos are in the wing  between the gear and the trailing edge.
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Old 06-11-2009, 12:49 AM
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Steve_S-RCU
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Default RE: Need Advice on my F-5

Hi Angelrcdesign,

Thanks for the info.
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