Spit/109 sea level speed comparisons in 1.08 beta patch

[ACE-OF-ACES]

Originally Posted by klem

More confusion because I understood the rough conversion to TAS is 2% per thousand feet

The key word being 'rough'

A few years back, while testing IL-2, I did a comparison between the gauge IAS to TAS values using the 'rough' conversion to the 'full' conversion using the IL-2 'internal' values obtained via SJacks ZINFOMOD.. I than graphed the two values side by side, at which point the word 'rough' came to light! In short this rule-of-thumb pilot real time in your head calculation is very 'rough', there are points (altitudes) where it is spot on, but there are other points (alts) where is is way off.

Originally Posted by klem

but I'm more inclined to trust the Z data and particularly Z_TAS.

Hopefully the soon to be released 'readme' will shed some light on the subject, but like you, I am leaning towards using some of the Z data values.. at least when it comes to speed measurements. They do seem to agree with the real world data better, at least for the few planes I have tested.

For now my plan is to provide both the Z and I values and let the user decide which to use with my CoD analysis tools that I provide online at www.flightsimtesting.com