Grove gear and CG

[fl-mike]

Grove gear owners: any issues with CG being too far aft when using Grove gear on a O-360 and metal prop? My buddy said his O-360 w/ MT CS is pretty good in terms of CG range and he though losing the gear weight forward might limit backseaters, etc.

I will probably use a metal prop, so that might balance it out.

Thanks

 

[David-aviator]

I have Grove airfoil gear with Superior IO360 and Catto prop.

Empty weight is 1029 and cg of 78.54
Similar spread sheet as Carl's shows with full fuel, pilot 200, pax 250 and 40 lbs of aft bags - aft cg of 86.67 and 1771 gross.

 

[skylor]

CG Change With Fuel Burn

Also, just a reminder that the CG moves aft with fuel burn. In my post above, if I load 42 gallons (compared to the 10 gallons in the example) the CG moves forward by 0.72 inches (the CG would be at 86.15 inches).

So if one took off with full fuel with the CG right at the Aft Limit, when you had 10 gallons left you would be aft of the Aft Limit by approximately 0.72 inches. Quite a lot, actually. And the pitch stability issues I mentioned in the earlier post, would be worse during the landing.

A word of caution: The above statement doesn't always hold true. The fuel datum is 80 inches and the allowable CG range is 78.7 to 86.82 inches. When operating with a CG aft of 80", the CG will move aft with fuel burn as stated. However, when operating with the CG forward of 80" (heavy engine and prop, light pilot solo) the CG will actually move forward with fuel burn...

Skylor
RV-8 (heavy engine and prop)...