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Mustang
07-22-2005, 04:44 AM
I Have a gws Mustang which I have modified by adding carbon fiber to the wings and a glass/resin shell to the exterior skin of the airplane. The firewall/mount was also reinforced with glass resin combo. as well as the entire fuse. All of the hindges for flightsurfaces have been replaced with robart hindge points. Just got a new Himax HG 2025-5300 brushless motor and Phoenix 25 amp controller using a 1700 ma li pol. The Plane weighs in at 20 oz after all that and the motor and prop combo should produce 40 oz thrust.
I cooked the 300 series motor that came with it so I am going to install the new one tonight. I just got back from the field where i was wringing out my 182 Skylane so after I get the oil out of my hair I am going to put the new motor controller in.

Any coments/ sugestions???

Reformed Nitroaddict
07-22-2005, 04:52 AM
Sounds like a champ - What gearbox prop combo are you running for 40oz of thrust? Thats hardcore. I can only get about 18oz of thrust out of my 2015 and keep it under 12amps.

Mustang
07-22-2005, 05:01 AM
6.60 gear ratio 3 cell li-pol with a 10X7 prop gives you 38.1 oz thrust at around 15 amps. The best part is I have a wing loading of just under 18 oz/ft.
But even with that the 300 series motor thaat came with it was blowing smoke after about 5 min of flight time. I can not wait to see how it will fly with the updated drive. The best part of all is I got to pull dead weight out of the nose the new motor is just heavy enough that it should be all that is needed up front to keep the cg in place. we will see...

Reformed Nitroaddict
07-22-2005, 02:31 PM
Very interesting - Keep us updated!

Reformed Nitroaddict
07-22-2005, 02:32 PM
BTW - the one common concern I have seen with others who have that plane is that it has a nasty tendency to tip stall - You seem to have already flown it a bit though, so I imagine you are aware of the flight characteristic by now though.

RickAvery
07-22-2005, 04:06 PM
Ive recently built up a GWS Mustang but went a slightly different route. I put a HiMaxx 2816 1220kv outrunner direct drive system in it. Using a CC25 ESC, 3cell, 1500mah 10c LIPo, and an APC 9045e prop, she flies excellent! 10 to 15 min flights with mixed flying. I wanted to eliminate the gear box and the associated hassles Ive encountered with them in the past. I also added much carbon fiber, 2- 1/8 tubes in both fuse halves nose to tail, a flat ribbon embedded in the bottom of the wing tip to tip, a small rectangle embedded edgewise in the horiz stab tip to tip, 2- uni-directional strips glued to the inside of the sides of the cockpit & 2 of the same type strips glued along the wing saddle flats on the fuse. She turned out to be 19.5 0z ready to fly. No landing gear. Hand launch belly land. Shell go straight up for about 200 and climb unlimited at about 70 deg. Not having a gear box is sooooo cool. She is why they are called silent fliers. Once you go outrunner direct drive, youll never go back. I know I wont. I think that once you put a brushless system geared or outrunner, the tip stall issue becomes a non issue as she accelerates so quickly past the stall speed you never notice it. You can tip stall them on landing though, but I found it NOT to be the demon it was made out to be. Under powered systems bring out bad traits that otherwise would not show up. With 50+ flights on her, she is the workhorse of my fleet right now. Ill throw up a pic when I get home. Good luck with your build!
Rick

Mustang
07-22-2005, 06:16 PM
WHen I put the carbon fiber in I installed it in the panel groves on top of the wings it was at that point the carbon fiber came flush with the top of the wing. I embeded it in epoxy and smothed it out so it was flush with the surface. One thing I also did was to shape both inboard sectons of the lower part of the wing to increase the aoa in regards to the wing tips. I did the same thing on the fuse. opting to put severl small thin pieces of carbon fiber instead of a couple of thicker ones. I agree with Rick it is a power issue with the airplane as it come out of the box. I would say that the airplane kit as it is sold is way underpowerd. If you note in the book it states the prop and motor will only give yu 9 oz of thrust (best case) that means that if you manage to build it and come in at the 12 oz design weight best case thrust to weight is only 9:12, or 75% of gvw.
But keep in mind guys this is a warbird, it will fly like one, quick response it not a stable flyer by any strech of the imagination. With out flaps a P-51 will exhibit a tendencey to tip stall when landing. That is why I made the change to the aoa of the inboard section of the wing, that mod. to the wing seemed to eliminate much of that problem. The drawback to that is I lowered the top speed a bit, but I don't see that as much of a problem as I am not chasing down ME 109's or 262's with it, lol
Paul

Joe Ortiz
08-01-2005, 08:50 PM
I'm currently building a GWS ME-109, it will be outfitted with an Aurora 400T brushless direct drive, 15amp esc, 2 cell lipo, Hitec HS-55 servos, 8x4 APC e-prop, it's main purpose is for e-combat, can't wait to try her out.

Joe

Reformed Nitroaddict
08-01-2005, 09:00 PM
How much power are you seeing with the 2S lipo? Any GWS plane I tried to fly on less than 9V just didn't have any power. A 7.2V pack just doesn't seem to have enough thrust to move a plane of that weight. Is the weight savings that good, that it offsets the lower voltage?

Joe Ortiz
08-01-2005, 09:47 PM
The plane is still under construction, this being my second electric, I don't know much about them, I'm a nitro plane kind of guy:eek: , are we allowed to say nitro here?:D , I do have a Kokam 3 cell 15C lipo as well, I can use all the sudgestions I can get.

Joe

Mustang
08-13-2005, 07:05 AM
UPDATE:

The Mustang will go vertical no problem.
I can get about 9 minutes of speed or 15 to 18 minutes of regular flight.

Cooling may be an issue when you are doing high speed flight although I have not seen any problems yet.

I have an old Top Flight Mustang that I am thinking about converting, if the cost come down.

E-Challenged
09-11-2005, 06:01 PM
UPDATE:
.

Cooling may be an issue when you are doing high speed flight although I have not seen any problems yet.
the cost come down.

Mike at Cheap Battery Packs told me that their PolyQuest 1100mah 3S should work well with my geared MiniAC1215/16 brushless but it must get some cooling air. I'm building and a GWS Zero and the battery compartment is too tight to allow much airflow over top and bottom of pack even though I have carved and dremeled it out as much as I dare.
I may have to mount the battery pack in the cavity above the aileron servo instead, which would require taking off the #$% wing to disconnect and charge the pack. Ideas?:confused:

Twmaster
09-11-2005, 06:08 PM
Hey E-Challenged, you are using the 1215/16 in the Zeke? Which gear set? I have a Zero and an ME-109 and a NIB 1215/20 looking for a plane.

E-Challenged
09-11-2005, 07:31 PM
Hey E-Challenged, you are using the 1215/16 in the Zeke? Which gear set? I have a Zero and an ME-109 and a NIB 1215/20 looking for a plane.

I have it in a "C" ratio gearbox now and will run 9x7 prop to get moderate 7.5 amp draw at cruise and 9+ amps at full throttle. This motor gearbox gave lively performance with 8-cell KAN 1050 pack in my Switchback, should be a little hotter with the PQ1100 3S pack. I'm just wary of insufficient cooling of pack in close fitting battery compartment in the Zero. I enlarged the compartment as much as safe and coated it with epoxy for strength. A thinner two cell 1100-1500 pack would allow more air flow but I don't have one besides I wanted a mild "hot-rod". A two cell pack with larger prop/different gear ratio might work well with your 1215/20 motor. Larger props can give unwanted torque and P-factor problems though. My Switchback always needed right aileron trim with 10-11" props. BTW, I plan to coat the inside of flimsy cowl with lightweight fibreglass cloth and epoxy and use larger 1/8" ply plates for the landing gear mounts and a bamboo skewer imbedded in the stab foam for added strength. Will cover bottom of wing tips with fiberglass cloth and epoxy.