Gnat mods
#1
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I have built and flown many HORs and like them very much. Friends are frustrated with trying to get the same performance from the Gnat. Is it possible to take the Gnat fus and tailfeathers and use a HOR wing and improve things? I saw a Gnat fus of 29 inches length mated to HOR horizontal stab and addition of small vertical stab and the thing flew extremely well. Maybe the Gnat fus is too short for my idea but am trying to recycle some abandoned Gnats
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Those two just do not perform the same. The HOR is a smooth flyer, the Gnat sort of bobs around. The nice thing about the Gnat is it's unpredictability and the fact that it has almost no "recovery" altitude to speak of after a mid air or a lot of hard turns. The name reeally fits this plane. They are two different styles of combat/flight, just pick your fav!
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A group of us have been flying the GNAT in combat for a few months. Many of us have gone to a CG of 3 3/4 from the leading edge instead of the suggested 4 1/4 inch. The GNAT is a better flyer when set up this way. More predictatable, has some useful glide, and behaves much better when inverted. Has anyone else seen the same thing? What other modification are out there? DickB
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We have been flying modified Gnats for 4 months and love them. The signs we originally used were only 32" so we streched the wing chord 1" to compensate. The first gnat proved a 15 was too small so we ar runnig 25s & 32s on them. They handle great at slow speeds and can turn ona dime. The key to making the stable is to raise the ailerons so that the tips are almost even with the top of the aluminum channel, otherwise they constantly want to climb at high speed and fall out of the sky at slow speeds. In the event of a major impact the recover nicley providing engine is running and all control surfaces are intact.
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A follow up question on the Gnat. I note on some that the airfoil shape is clear near the fus but rapidly fades away as you move to the wing tip. Do you need to maintain the airfoil shape to the wing ends? Is this done by lightly creasing or folding the coro? Thanks, I have several SPADS but none with this airfoil shape and expect the same question when building the PQHOR style plane.
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The airfoil shapes on our GNATS is consistent across it's length - although this is not all that critical. Some of us have but receivers in the "gap" along with batteries, this plus foam can result in a bit of a bulge, but has not made any apparent change in flight characteristics. I like to use a piece of 1/2 inch thick foam at the wing tip, held in place with hot glue and the coat hanger "clip". Doing this helps to keep things "crisp". Are you slitting the coro along the five veins you make the bend over? DickB
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I have not found the crease to be a problem but am not able to bring the airfoil shape to the end of the wing. It is present near the fus but fades toward the tips.
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FrankC29
YUP.... a heavy duty coat metal coat hanger at the tip of the wing helps. That and the foam works great. 1/2 inch between the "legs" of a u-shaped coat hanger seems to do the trick. DickB
YUP.... a heavy duty coat metal coat hanger at the tip of the wing helps. That and the foam works great. 1/2 inch between the "legs" of a u-shaped coat hanger seems to do the trick. DickB
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ORIGINAL: Barland
A group of us have been flying the GNAT in combat for a few months. Many of us have gone to a CG of 3 3/4 from the leading edge instead of the suggested 4 1/4 inch. The GNAT is a better flyer when set up this way. More predictatable, has some useful glide, and behaves much better when inverted. Has anyone else seen the same thing? What other modification are out there? DickB
A group of us have been flying the GNAT in combat for a few months. Many of us have gone to a CG of 3 3/4 from the leading edge instead of the suggested 4 1/4 inch. The GNAT is a better flyer when set up this way. More predictatable, has some useful glide, and behaves much better when inverted. Has anyone else seen the same thing? What other modification are out there? DickB
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TwoStroke,
We are doing it with a 34 inch wing and 24 inch fuselage. Throttle servo mounted in front of a 4 oz tank... front of the tank just about even with the front of the wing. 15LA with the blue 8 X 3 prop... The ailerons are pulled up, reflexed I believe it's called, so their trailing edge is just a bit above the bottom of the fuselage. DickB
We are doing it with a 34 inch wing and 24 inch fuselage. Throttle servo mounted in front of a 4 oz tank... front of the tank just about even with the front of the wing. 15LA with the blue 8 X 3 prop... The ailerons are pulled up, reflexed I believe it's called, so their trailing edge is just a bit above the bottom of the fuselage. DickB
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Still not sure I made my point clear. I am speaking about the look of the wing profile on the instructions. It appears to have an airfoil going from fus to wingtip on each side of the plane, but in practice I see most have only some slight airfoil near the fus and a flat wing near the tips. The foam and coat hanger don't affect the airfoil that I can see.
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I think I know what you mean now, and I've had this too. It doesn't seem to effect the flight any that I can tell, might even add a bit of a stabilizing dihedral effect, who knows.