Mark and Jeff are both correct in saying the spinner is not the ideal place to choose as a datum to calculate W&B as that point could change in the future and cause self induced errors. I was addressing Pete's concern that using the spinner was giving him errors in his calculations. I was simply saying that the spinner is as valid a datum point as any other point he chooses for his calculations as long as his measurements and math are correct. It does add a small factor of complication to the process as the arm increases with each movement of the engine but with minds like ours that should not be a major hurdle. I would also suggest that Pete pick a more appropriate datum for the future aircraft records. I used the forward face of the 5 inch prop extension on the 0-200 and that is noted in the aircraft log as well as the W&B sheet in the aircraft.
Larry Flesner
