CG on CAP 232 60

Hi!

When balansing my CAP232 60 (tank empty) I have to add 565 grams in the front for proper balancing??!! The tank is 1/2 l which is 500gr. But hove much waight do I need to add to be able to land the machine with tank at 1/4 fo example??

I'll appreciate input

Reply to
Kajman
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Sounds a lot of dead weight!!?

What about moving your engine more forward on the engine mount? If possible, that will at least reduce the amount of ballast needed for proper balance.

Regards, Erik, Soerstraumen Air Devils

Reply to
Erik Gunnes

The engine is mounted on a standard Saito mount as far as possible to the front. My concern is really if Kyoso weigh their planes with full tank or not. If not, I have a hard time understanding how an ARF with proper engine and no extras in the back should need another 1/2kg to balance??!! (Rx and Ack ar also positionerd as far to the front as possible). If they weigh them full tank, then I understand because the standard tank is 1/2 ltr=500gr, that would mean 50 gr extra in the front, acceptable.

Reply to
Kajman

Ballancing the aircraft with empty tank should be the normal procedure.

I have no experience with Kyosho, but my ARC abs-plastic models are pretty good in ballance straight out of the box....

Regards, Erik

Reply to
Erik Gunnes

You should ALWAYS balance any model at ZFW (Zero Fuel Weight). ie: With an empty tank. This is a universal convention. The practice, which incidentally is also practiced in full size aircraft, is based upon the worst case scenario of a maximum aft CofG given that our model fuel tanks are invariably simple single fuselage tanks mounted forward of the CofG which moves aft with fuel burnoff.

It beggars belief that Kyosho would contravene this without specific mention. It must be asked if you read the instruction (assembly) manual?

Stating the obvious why don't you see if you can either move the engine forward or anything aft of the CofG further forward first. ie: move battery pack, servos or receiver etc forward of the CofG if possible or at least further forward than they already are.

You mention in another post that you have installed a Saito 100. How could it be tail heavy with this anchor up front? :)

Seriously though. I'd crosscheck your CofG. Most likely is either you've misread/misplaced the CofG or Kyosho have specified an erroneous one. I suggest you place a post on RCU asking owners of the specific model if they are aware of any addendum to the spec CofG.

½kg up front as ballast is excessive and should indicate to you something is severely wrong. Even if it were a Vietnamese ARF I'd be surprised, but Kyosho wouldn't get it that wrong.

Just an advisory.

The SG (specific gravity) of methanol is .79 not 1.0. Oil is .92. I can't recall or quickly find the SG of nitro but it would lie somewhere between the two. In any case the small amount we use is insignificant in terms of any significant effect upon the overall fuel's SG.

As methanol constitutes 70 to 75% of the fuel for most users, if we use a figure of .8 for ease of arithmetic (ignoring the additional .016 derived of the mean) which takes into account the weight of oil in your fuel, we have a more accurate approximation for DR calculations.

On this basis ½ litre of model fuel would actually weigh 400g not

500g. K
Reply to
K

You need to add it all. Balance it with no consideration for fuel. Then you can fly it and decide if you want to take some out to move the CG back.

CR

Kajman wrote:

Reply to
Charles & Peggy Robinson

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