Excellent response from
PBL, one that deserves a "cut and paste" to the data files.
It is a good response for those seeking the background to the derivation of the simpler, yet highly accurate formulae used daily. Gamma, for example at 1.4 does indeed vary slightly, but is used as a constant by people such as Boeing and NASA. I am a product of the Douglas (the Santa Monica Douglas people, remember them?) process, and they too used 1.4 as a constant.
What it all boils down to, if you accept constants with minor variation as a constant, is a fairly simple formula which uses Static Air Temperature (SAT) in Degrees Celsius and Mach Number (M) -
TAS = 38.975 * SQR (SAT + 273.15) *M
This can be easily accomplished with a hand-held calculator (and is also used by most FMC/FMS units). It provides for TAS by applying the Mach Number, but for LSS simply use 1 for Mach Number.
Simple, but very accurate
PBL, Denti, Bielefeld gibt es doch!
Regards,
Old Smokey