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Magnum R throws & CG

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Magnum R throws & CG

Old 11-01-2006, 11:57 PM
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rockhouse
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Default Magnum R throws & CG

Putting my Magnum back on my radio & can't find the paperwork. I need the Ail & ele throws & the CG. Any help is appreciated.
Old 11-02-2006, 01:31 AM
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Razor-RCU
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Default RE: Magnum R throws & CG

I would do a search since the CG was WAY OFF from the man. I dial in triple rates and make sure that on th highest rate, I get a TON of Elev. throw for landings...

Seems like 145CM was the base CG-
Old 11-02-2006, 11:43 AM
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MJD
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Default RE: Magnum R throws & CG

I have my manual here in my desk for some reason, and here is what it prescribes:

Elevator - 10mm up and down
Aileron - 8mm up and down

I used to use triple rates, but I fly single rate with a lot of expo now after getting used to the airplane. 10mm is a LOT of throw for flying at speed, but you'll use it up on landing esp. with forward CG's.

The recommended CG is 120-130mm "from the wing root" - meaning that it is measured from the LE at the root.

The recommended CG is very, very forward however. I did a NP workup on the Magnum and was shocked to find out where the CG would be located if calculated by normal methods with normal static stability margins - 190mm plus!

The standard recommendation is now 135 - 145mm. You'll be fine starting at 130 - 135, then moving back as you see fit. Naturally the induced drag is higher at the more forward CG's, and the already tough job of flaring on landing becomes even tougher.

Hope this helps.

MJD

Old 11-02-2006, 03:53 PM
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Default RE: Magnum R throws & CG

Thanks, that should get me going.
Joe
Old 11-02-2006, 09:57 PM
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cobratraxxas69
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Default RE: Magnum R throws & CG



These are my low rates on my Magnum (used for most of my flying--they are conservative settings):

Ailerons: up 2mm/ down 2mm
Elevators: Up 7mm/ Down 7mm
Old 11-02-2006, 10:08 PM
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Razor-RCU
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Default RE: Magnum R throws & CG

2MM Cobra? That is VERY little...

I probably have an inch up and down on Elev. and 3/4 on AIl.
Old 11-03-2006, 10:13 AM
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MJD
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Default RE: Magnum R throws & CG

ORIGINAL: Razor-RCU

2MM Cobra? That is VERY little...

I probably have an inch up and down on Elev. and 3/4 on AIl.
The elevator chord is one inch, as is the aileron. I assume you mean total throw, as in 1/2 inch up and 1/2 inch down, i.e. 12.5mm on the elevator? That's 26-27 degrees deflection. Otherwise you'd be the first person I've heard of flying 3D with a Magnum! It still seems like a lot though. I like mine much better once I dialed down the throws all around, saving the large elevator throw until the end of the stick's travel for flare.

It would not surprise me at all that at speed 2mm is more than enough for a decent roll rate.

MJD

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