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Old Dec 16, 2002, 03:36 PM
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yb2normal's Avatar
Broomfield, CO, USA
Joined Jan 2001
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How much Bandit pitch-up on spoiler deployment is ok?

First, thanks to the tremendous amount of information here on the 'zone regarding the FVK Bandit, I was not a *complete* wreck on my first flight

I have all the control surfaces set up per the mfg stated throws and I now have two questions:

1) When I hit the spoilers (on a switch) the model shifts to a slighly nose-high attitude and holds this angle all the way onto the ground. The first time I tried it at altitude I reflexively pushed the nose down, but then I let the nose back up and it settled into the nose high position and kept gliding... albiet a bit slower and steeper decent. I then tried it on approach and let is just settle onto the ground in this position. It slid maybe 10 feet at the most. Does this sound reasonable?

2) My rolls are very non-axial. The difference between the up and down ailerons seems pretty significant and I suspect this has something to do with it, do all you guys who get nice looking axial rolls have mfg recommended throws? Or did you increase the downward aileron?

Thanks for the help,
Bill
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Old Dec 16, 2002, 04:01 PM
Foamie Hater
Joined Jul 2001
308 Posts
1)You should put your spoilers on the throttle or a slider so you can manipulate it accordingly. Some models require some down elevater mixed in with the spoilers, Just a little.

2) You might try moving your cg and playing with you differential. Try 40%-50%. Play around with it until you get a nice axial roll.
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Old Dec 16, 2002, 05:16 PM
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Dave Wenzlick / Slickraft's Avatar
Mesa AZ
Joined Jun 2001
655 Posts
The landing angle sounds pretty typical. The nose can stay up during landings as long as you aren't at risk of stalling and you are still able to make flight path adjustments as you line up to land.

For axial rolls I have 100% throw up and only 50% throw down. As flyerman states, get your CG where you like it and then adjust the aileron differential throws for axial rolls. Your placement of the control horns during building can affect the differential slightly from your plane to mine. Also remember that an axial roll at high speeds might not be as axial at slower speeds.

Have fun.

Dave W.
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Old Dec 16, 2002, 06:29 PM
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Broomfield, CO, USA
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Thanks for the quick replies.

I suspect my down movement is less than 50% of up movement so I'll increase it a little bit. I have the linkage set up to provide some mechanical differential, and probably over did it a bit when programming the extra amount in the radio.

I'll also start working the CG back as I get more comfortable with the plane.

Beautiful little thing, I have to say
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Old Dec 16, 2002, 10:00 PM
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Andy W's Avatar
Marietta, GA
Joined Jun 1999
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- nose-up is good. Why do you think it slows down? Not the spoilers! The wing makes a monster flap, the aileron deflection just elimnates any risk of stalling! My F5B/hotliners all have more skid marks on the bottom of the fin than the nose!
- You are using aileron differential, right? v. little down, vs. lots of up? Personally, I think barrel rolls at 100mph look cool..
..a
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Old Dec 17, 2002, 10:24 AM
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- nose-up is good. Why do you think it slows down?

It seemed like it slowed down to a slightly slower speed, but that could definitely just be my perception. Now that I think about it, I remember being surprised at how fast it continued to cook along in that funky nose up attitude.

The wing makes a monster flap, the aileron deflection just elimnates any risk of stalling! My F5B/hotliners all have more skid marks on the bottom of the fin than the nose!

Good, so the angle is typical. Thanks for the explanation of the spoiler usage... I wondered how it managed NOT to tip stall into the ground with the nose up like that.

- You are using aileron differential, right? v. little down, vs. lots of up? Personally, I think barrel rolls at 100mph look cool..
..a


Yes, LOTS of differential, partially mechanical and partially programmed. I agree that there is something awesome about seeing a plane whip around like that at an obscene speed, I guess I was comparing the roll to many of the online video's I've seen of the bandit and their rolls looked much more axial than mine. I might have a bit too much differential really. It's hard to see on such a small plane at such a distance, but the way it wobbles out of a turn makes me suspect I'm skidding the nose *inside* the turn. This is with the mfg recommended cg.

- Bill
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Old Dec 17, 2002, 03:41 PM
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Andy W's Avatar
Marietta, GA
Joined Jun 1999
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As far as slowing goes, my falcon and sirius will drop from 100mph or more from a fast fly by, or 50-60 if in the pattern, to almost a walking pace (OK, a fast jog) in just a couple of seconds with spoilers deployed. The Smart will not slow quite as easily, however..
..a
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Old Dec 17, 2002, 07:21 PM
tic
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New Cumberland, PA. US
Joined Dec 2000
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funny you should mention axial rolls w/ the bandit... I USED to get them, now I don't... CG has gradually been moved AFT... I think I need less differential now... and exactly what is LESS differential?.. you can look at it two ways.. Right now, I'm at 100% up and 50% down. To me, LESS differential would be like 100% up and 75% down.. agreed?.. I hate to introduce all that drag from a downward deflected aileron, but the barrel rolls aren't pretty, IMHO
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Old Dec 17, 2002, 11:16 PM
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Broomfield, CO, USA
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Quote:
Originally posted by tic
To me, LESS differential would be like 100% up and 75% down.. agreed?..
Yup, that's where I'm headed.
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