Al Fernandez
02-01-2010, 08:14 AM
A discussion went around for a bit on max and min numbers and tolerances, and I want to post something to hopefully clarify. The CMC book and the CCR both have a tolerance rule which applies to all specified measurements. This means all measurements defined in the book: ride height, wing height, power, weight, etc. Its rule 3.11.
The practical meaning is for CMC all specified measurements come with a measurement accuracy tolerance of +/- 1/2 of the last specified number place. So, a max wheel width defined as 9.5" means the measurement is 9.5 +/- 0.05. A max compression specified at 11.0 means 11.0 +/-0.05. A max weight of 3200 means 3200 +/- 0.5.
Because CMC specifies a tolerance for all measurements (including weight) and because class rules supercede the nasa CCR, the CCR's weight tolerance of 5lbs for the first time you get weighed in any given weekend does not apply. The CCR's leeway does apply to AI however because the AI book does not specify a tolerance and relies on the CCR for this.
Hopefully that makes sense.
The practical meaning is for CMC all specified measurements come with a measurement accuracy tolerance of +/- 1/2 of the last specified number place. So, a max wheel width defined as 9.5" means the measurement is 9.5 +/- 0.05. A max compression specified at 11.0 means 11.0 +/-0.05. A max weight of 3200 means 3200 +/- 0.5.
Because CMC specifies a tolerance for all measurements (including weight) and because class rules supercede the nasa CCR, the CCR's weight tolerance of 5lbs for the first time you get weighed in any given weekend does not apply. The CCR's leeway does apply to AI however because the AI book does not specify a tolerance and relies on the CCR for this.
Hopefully that makes sense.