Where these numbers came from?
Please be adviced that:
- a friction number is not a property of a surface. It is generated from a pair of surfaces in relative motion.
- a friction number must always be related to the measuring instrument used. (Friction measuring device, aircraft, etc)
- there is a lot of uncertainties related to the generated friction numbers.
- a friction number with multiple decimals (0.261) is not an "accurate" friction number.
- the term "accurate" can not be used together with a friction number as we do not have an universially agreed reference. The correct term is UNCERTAINTY
- the uncertainty involved when it comes to operation of aircrafts is in the order of 0.1