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Old 11-06-2013, 03:46 AM   #26
FreeSparrow
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Dave,
I will check the engine mount on Friday and verify if it is mounted Zero Zero.

Another (maybe crazy) idea that I have is to kill two birds with one shot.
Can I install a smoke system in front of the CG?


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Old 11-15-2013, 01:55 PM   #27
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I have a couple hundred hours in Lowell Slatter's 300hp Acroduster II. It always felt tail heavy especially when two up even though it was within the CG envelope. We started to build two new ADIIs and one thing we did was increase the horizontal tail area around 15% as we felt that the small tail was the problem. Basically the same area of the Christen Eagle. Never did get them done, maybe someday soon. He is going to re cover his airplane soon and when he does he will put the bigger tail on it. Don


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Old 11-16-2013, 05:46 AM   #28
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...Which brings me to another (totally un)related subject.
The control forces.
It takes a great deal of force to execute maneuvers that require full and rapid deflection of ailerons or elevator, especially when compared with the Extra 300 or Su-29. I am seriously considering replacing the original stick with a longer one. Didn't have a chance yet to do the precise measurements, but in my opinion, an additional 6 - 9 inch will decrease the force required for quick full deflection significantly, which in turn will improve the overall roll-rate by 10% - 12%.
Does anyone have anything to add on this issue?

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Old 11-16-2013, 01:06 PM   #29
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May I ask whether the relationship of the control forces between the ailerons and elevator feel appropriately proportional? If they are, then you will want to maintain that relationship. This is called control "harmony" and is a big contributor to a pilot being able to precisely fly the airplane.

Making the stick that much longer is likely to reduce the total control motion available. If you want to use the roll rate available at the limits of the control travels, the longer stick will likely keep you from doing that unless the cockpit and the space between your legs, and between the panel and your belly is much larger than I am visualizing.

The improvement that you want can be obtained by redesigning the elevator and ailerons, but then you are into the cycle of building multiple airplane parts, test fly, throw parts away and build new, rinse and repeat, until you have the control feel and harmony that you want. In truth, if you would rather just fly for fun you should likely just trade for a Pitts.

Historically, I understand Henry Haigh tried a discouraging number of tail feather modifications without success until Curtis Pitts, through Linda Meyers-Morrissey, slipped him a hint which produced the final design of his monoplane. Henry Haigh won the world championship at age 64.

Its easy to cut some tube for a longer straight control stick. Should be interesting to see what you get. Please post your impressions if you fly it.

Best of luck,

Wes
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Old 11-17-2013, 04:08 AM   #30
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Lengthening the stick will increase the time in transit from full left/forward to full right/back stick. This effort might end up being a wash. If I were you I would try to get a time to go, say from level stable flight to level flight with an aileron roll before and after change. My guess it will be more a personal impression than a real difference.

L

PS: It may take some experimenting to find the right length that gives you the rate you want with the effort you are comfortable with.
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Old 09-13-2017, 11:11 PM   #31
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free sparow ... wondering if you ever got to the bottom of the pitch trim issues.

Would appreciate a report
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Old 09-14-2017, 09:48 PM   #32
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I had the same problem with my Starduster,i decreased the wing incedence and it fixed the problem,now flies neutral at 115 knots,lands better as well.
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Old 09-14-2017, 10:55 PM   #33
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Yeah, i am wondering if it wasn't rigging related.

I was trying to figure out another members issue with pitch after a canopy installation, and wondered if that may have been the issue.
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Old 10-07-2017, 07:14 PM   #34
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Yea, we never got to the bottom of this aircraft's issues. FWIW my AD2 incidences were all zero.......

Jack


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