2018/08/05

Why point is used instead of decimal in CS documents (EASA)

You may wonder why EASA uses "·" instead of "," symbol for decimals in the CS Certification Specification documents (e.g. CS-23, CS-25, ...).To clearly understand the problem, see this example:

CS-25.355 (e)
"(3) VF may not be less than –
     (i) 1·6 VS1 with the wing-flaps in take-off position at maximum take-off weight;"

The reason is that they use the spoken name of the symbol, such as "point" instead of decimal. In our example: one-point-six times the stall speed in a specified configuration. Don't confuse it with multiplication.

On the other hand, in ICAO radiotelephony the "," and the "." symbol must be pronounced as "decimal", and not as "point", for avoiding confusion. (See ICAO Annex 10, Volume II.)