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Swift cannot break ground with these blade pitches

Old 04-01-2007, 11:58 AM
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bdelmonte
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Default Swift cannot break ground with these blade pitches

Flight Mode Low Stick Half Stick High Stick
Normal +11 degrees 0-1 degrees -8.5-9 degrees

Both Throttle curve and Pitch curve are set linear from 0 to 100.

I cannot break ground with these blade pitches. What is wrong here and how do I correct it?
Old 04-01-2007, 12:55 PM
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Default RE: Swift cannot break ground with these blade pitches

Either to heavy or there is something wrong with the pitch setup when the blade is turning
Old 04-01-2007, 01:07 PM
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Default RE: Swift cannot break ground with these blade pitches

Yes, the pitch is reversed here. Is this a mechanical set-up problem or electric set-up? What is the remedy?
Old 04-01-2007, 01:26 PM
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Default RE: Swift cannot break ground with these blade pitches

So are the blades going to a negative pitch when you move the stick up? Is the head spinning backwards?
Old 04-01-2007, 01:44 PM
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Default RE: Swift cannot break ground with these blade pitches

Yes, blades going to a negative pitch when I move the stick up. The main rotor head is spinning clockwise, as expected.

I believe that the current mechanical setup is not proper - i.e. the swash moves up causing an decrease in blade pitch.

I will look at fixing the linkages, but need help where to start here.

Pitch curve is set linear from 0 to 100, withSpectrum DX7 settings as default for Norm (same for ST1, ST2 and hold):
Point L 0.0%
Point 1 inh - should I change to 25%?
Point 2 50.0%
Point 3 inh - should I change to 75%
Point 4 100.0%

Old 04-01-2007, 04:56 PM
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Default RE: Swift cannot break ground with these blade pitches

I am not fimilar if the swift is eccpm or mechanical. If it is mechanical you can simply reverse the direction of the pitch servo. If it is eccpm i believe you will have to reverse all cyclic servos
Old 04-01-2007, 05:31 PM
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Default RE: Swift cannot break ground with these blade pitches

The Century Swift is eccpm. After I reversed all of the cyclic servos (aileron, elevator, and pitch), the main blade pitch is now correct:

Flight Mode Low Stick Half Stick High Stick
Normal -8 degrees 2 degrees 12 degrees

Thus, when I increase the throttle, the swashplate lowers (previously raised) and this heli is ready to break ground.

Now, I need to figure out how to get a Futaba Gyro GY401 to work (not currently observing red light solid) to control the rudder direction (spinning now).
Old 04-01-2007, 06:33 PM
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Default RE: Swift cannot break ground with these blade pitches

There is still something wrong (I suspect you have the blade grip pitch arms reversed). The blade pitch arms should be oriented to the leading edge of the blades when the blades are turning clockwise.

Then as your swashplate moves UP - your blades should INCREASE in pitch.

Also your pitch range is wrong (specially for training)

I would suggest, with your eccpm, and everything defaulted (pitch and throttle curves) to linear, that at mid stick the servo arms should all be set so that they all orient at 90 degrees to the servo cases (as shown in the instructions). When you move the stick up, the swashplate should move up.

Then back at half stick set the rods from the servo arm to the swashplate so that they hold the swashplate level about 18mm above the top of the mainframe. Then adjust the links from the inner star to the bell mixer, and from the washout arm to the bell mixer, so that at that mid stick position, the bell mixer and washout arms are level and the blade pitch is 0 degrees.

Now go into the pitch curve settings, and set the top number to give you +9 degrees when the stick is all the way up, about 4.5 degrees when the stick is at 3/4, and about -1 degree when the stick is at 1/4 and -2 at low stick. This will give you a very manageable (more docile) collective for training - later, when you go into arobatics you can dial in an idle-up aerobatic mode with more negative (e.g. -5 at 1/4 stick and -9 at bottom stick)

Then for the throttle, on your electric, you will want 0 at the bottom, something like 70% at 1/4, 90% at 1/2, 95% at 3/4 and 100% at full stick. NOTE: due to how electric current and ESC work, the throttle curves are set much differently for electric motors then for nitro engines.

Later when you adust your idle-up mode for a throttle curve that goes 100/95/90/95/100
Old 04-02-2007, 09:57 PM
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bdelmonte
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Default RE: Swift cannot break ground with these blade pitches

I will download Finless Bob's video on the Swift head setup to help me figure this pitch correction.

Thank you!
Old 04-03-2007, 08:39 PM
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Default RE: Swift cannot break ground with these blade pitches

Finless Bob's video on the head (build) parts 2 and 3 showed me how to fix the incorrect installation of blade grips. I also found head setup to be very helpful.

Bob, thanks again. You ROCK Dude!

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