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HELP funtana 125 dle30

Old 03-12-2012, 07:25 AM
  #1  
gwweber
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Default HELP funtana 125 dle30

Lord help me ive doen it again. Built a funtana 125 this winter. Installed a 30cc dle in it as i read that everone was putting like 8 ounces of weight in the front. I moved the firewall back. (very good job) and kept all the angles the same. Unded up having to put two washers on the bottom of the mounts as the plane wanted to pull to the ground whenever i gave it gas. I am runnong a three blade prop in it and it is now flyinf very well. One big issue, Landing is a ***** cause it gets er pitchy at low speeds. It tracks and flies perfect and when flown upside down no correction is necessary flies flat and level.
The balance is supposed to be spot on according to the manual, so in the beginning it is nose heavy cause of the tank fill.

The point here is that the plane is way overpowered and is it possible that the three bladed prop is causing the pitch issue when the plane is slowing down to land? Can it be acting as a big airbrake and causing the pitching. Otherwise it is an increadable plane to fly.

HELPMEPLEASE
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Old 03-12-2012, 12:47 PM
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da Rock
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Default RE: HELP funtana 125 dle30


ORIGINAL: gwweber
The point here is that the plane is way overpowered and is it possible that the three bladed prop is causing the pitch issue when the plane is slowing down to land? Can it be acting as a big airbrake and causing the pitching. Otherwise it is an increadable plane to fly.

HELP ME PLEASE

It's not the 3 blades that's the problem. It could be the pitch, but the problem from that happens when you got too much pitch and can't idle the engine any lower. Then you're stuck with too fast a landing speed. Now, if you're stuck with too fast when landing, the elevator could seem too sensitive compared to other planes you've got landing slower than this one.

If whatever prop you're using is acting as an airbrake, the problem it might cause would go away once the speed stabilizes. Usually.

The problem is pitchyness, right. So work directly on that. Try more exponential on the elevator. Or use your low rates and dial them down until they give you what you want.... or you get into where the elevator won't do the job (not likely if it's too effective to begin with). Now, if the pitchyness is in one direction only, maybe the CG is too far forward, but that doesn't match up with your inverted flight needing no trim. so......

I'd try adjusting elevator throw first. That's what can easily fix pitch sensitivity. I almost always fly everything of mine with the CG aft and every one of my model's elevator throws are way under mfg suggested throws. Never ran out of elevator either.
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Old 03-12-2012, 12:52 PM
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Default RE: HELP funtana 125 dle30

BTW, what I've always found with too much power has been lack of low speed throttle. The left stick is pretty much just an on-off switch. And landings can be a pain without any real low end throttle available. Sometimes trying to give a click or two on approach just launches the sucker back into Mach speed. If the thrust line isn't spot on, it'll show up then. Also, any "torque" issues show up in spades when you are trying to throttle just a touch. Ain't no touch to be had.
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Old 03-12-2012, 01:41 PM
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Default RE: HELP funtana 125 dle30

I'll try to measure the CG on mine. It's got a DLE30 too and I did not move my firewall. Yes, if it is just a touch tail heavy it takes some effort to get it on the ground. For the wing area this thing has it is very light leaving it with a tendency to want to float as the tail drops when slowing down. I have found a happy medium on the CG where with good throttle management I can do greaser landings all day long. With the SFG's on it, rolling harriers and knife edge flight is awesome. There is NO wing rock in harrier flight nor in a elevator with the SFG's. I am running 45 degs of elevator travel with my lowest rate set at 25% and 10% expo. The highest rate is 100% so I can get all 45 degs of elev travel and the expo is 70%. I am using a DX8 and have the throttle curve set to 0 18 45 75 100. I am thinking about picking the 18 up to 20 as it's just a tad soft down on the low throttle range. It's got a 19X8 XOAR on it and I have NO trouble getting a low enough idle for good slow landings.

I'll post the CG as soon as I get time to check it but I just kept moving it forward tiny bits until the plane flew as I desired. Good luck getting yours ironed out.
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Old 03-12-2012, 02:09 PM
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Default RE: HELP funtana 125 dle30



thks it is not an expo issue it seams like a balance issue it flies very very well just very hard to land. i guess the cg needs to go forward but i had it set to the book with a full tank. Jesus it is a torque machine

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Old 03-13-2012, 06:45 PM
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Default RE: HELP funtana 125 dle30

ORIGINAL: gwweber



thks it is not an expo issue it seams like a balance issue it flies very very well just very hard to land. i guess the cg needs to go forward but i had it set to the book with a full tank. Jesus it is a torque machine

I can't remember ever hearing of a model that was balanced with the tank full. Doing so (unless it should be that way) would cause it to be balanced tail heavy and of course that increases pitch sensitivity. I'm betting that the sensitivity got increasingly worse with flight time as it burned fuel. There has been many a model that was manageable at the beginning of a flight but became unmanageable and crashed as fuel was burned. I had one... a Spitfire... flew great for a while and then it got exciting and then it got more than exciting.
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Old 03-14-2012, 03:06 AM
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Default RE: HELP funtana 125 dle30

lol   i ment empty   with the tnk full you would think the weight would be far enough forward to make up for the cg being a tad off in the manual
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