Looking at the weighing document, I see a few things that would want me to reweigh the plane.

They weighed it full fuel, not empty, they used 5.8 lbs/gal fuel density (average in the US is 6.01 lbs/gal), the 2070 lbs on the nose jack point seems off to me, the empty CG is out the forward limit, and the weighing is 22 years old.

There is also a glaring math error, they computed the nose jack moment as 2070.0 but the moment has zero arm, so the moment will be zero regardless of the weight at that point. The empty weight won't be affected by this, but the CG is. When you fix the error, the real empty CG is now 37.30, or 0.57 inches more forward than listed.

Making sure a plane is within weight and CG limits is very important, so I would counsel any buyer to have it weighed to be sure. I routinely find errors in CG computations all the time, and this one is no exception.

Mike C.

Looking at the weighing document, I see a few things that would want me to reweigh the plane.

They weighed it full fuel, not empty, they used 5.8 lbs/gal fuel density (average in the US is 6.01 lbs/gal), the 2070 lbs on the nose jack point seems off to me, the empty CG is out the forward limit, and the weighing is 22 years old.

There is also a glaring math error, they computed the nose jack moment as 2070.0 but the moment has zero arm, so the moment will be zero regardless of the weight at that point. The empty weight won't be affected by this, but the CG is. When you fix the error, the real empty CG is now 37.30, or 0.57 inches more forward than listed.

Making sure a plane is within weight and CG limits is very important, so I would counsel any buyer to have it weighed to be sure. I routinely find errors in CG computations all the time, and this one is no exception.

Mike C.

If the arm for the nose jacking point is zero, then it is at the reference datum.

But the math is still wrong since an arm of zero produces no moment about that point. The moment would be 2070 in lbs if the arm was 1.0 inches, not 0.0 inches.


I assume there are two main jack points with the same arm, and their weights are added before entering on this form.

It is usually good form to list the main weights separately so that any math error adding them together is detectable. Just putting down the total of the two scales is bad form, IMO. Also, using two weights you can compute left/right CG which can be useful to detect weird issues (like you didn't really get full fuel on one side).

Get the plane weighed by a competent shop, empty fuel, so you really know what your empty and CG are.

Mike C.

Few interior pictures

More pictures

It's a cheap Colemill 310 that will haul whatever you put in it. Had one 25 years ago. Would climb on one engine 500 FPM at gross weight. I wouldn't worry about the W&B.

Maybe not the W but the B matters!

Agreed, but that plane will haul 4 adults and full fuel no problem or 4 adults, 3 hours plus reserve fuel and bags. Very similar to the B55 PII.

And the B looks nose heavy, especially when you consider the math error evident in the W&B showed here.

Disregarding the W is also stupid. If you find yourself on a warm day at some mountain airport, you might want to be careful with OEI climb performance despite the bigger engines.

Mike C.

Good valid points all, the plan is to have the weight and balance redone at the next annual. Which I may have done at TAS, but I’ve ran all the numbers in foreflight, had 4 adults today, full fuel and 100lbs luggage. Flew great no issues, Cg is a bit forward but not out of the envelope. 10000 ft, 26 gal per hour, 180 mph indicated, 200knts gsp. Made it from Riverside to Vacaville in 1.50…sure beats driving! Soon as I landed got a rental car and a kid hit me in the parking lot. I was stopped! Just ran into me….

How do you know?

The sheet you showed me had a math error which meant the real CG is more forward than the number it provided.

Having the plane weighed will reset all the errors and issues and let you know what you have.

Mike C.

Like you said until I have it reweighed I don’t for sure know. What I am counting on is that this is a certified aircraft with no major modifications beyond the Colemill STC and using generic numbers for a turbo 310Q and not ever getting very close to max gross I stay conservative in the envelope. There is a YouTube channel where he goes through many different configurations on a 310q and it illustrates this. But point clearly taken and I do want better more up to date numbers. Thanks for helping to keep me and mine safer as we operate these 50 year old airplanes.

Found yet another later version! Plane still available by the way.