Thunderbolt 'mania' (P-47M-1-RE) patching blues ;(

>That's exactly our point, Tom's aircraft is not as accurate>as the ones we have as reference and doesn't match historical>performance figures by a wide margin.>It looks like Tom made a basic error and inserted mph figures>into the performance tables where FS expects to see knots,>that's a more than trivial deviation.And this point isn't a point, because obviously ALL your assumptions are erroneous! Just two 'simple' questions - what's a 'wide margin' for you? And what's your reference aircraft?Now let's see - once more - first of all - I haven't 'inserted mph figures into the performance tables where FS expects to see knots' - because:1) there are no such 'tables' - at least not there, where you might think they should be!2) FS9 does indeed expects knots for all VALUES in the {Reference_speeds} section - and I did just that, inserted 'knots' - but not just knots - it is more complicated:-- all parameters in the above mentioned {Reference_speeds} section except two (2) are expected to be KTAS = knots TRUE airspeed!-- the first exception is the parameter 'max_indicated_speed', where FS interprets the value from there as KIAS = knots INDICATED airspeed-- the second exception is the parameter 'max_mach' - that one is not important, because the model in question is a piston driven one and the FS engine applies this only to turbine driven aircraft.Now let's see what I'm using in 'my' aircraft.cfg of the P-47M-1-RE in 'question':flaps_up_stall_speed = 89.5 // knots true airspeed KTASfull_flaps_stall_speed = 73 // knots true airspeed KTAScruise_speed = 195 // knots true airspeed KTAS max_indicated_speed = 548 // knots indicated airspeed KIAS (Vne) What does that mean? ==> The aircraft will overspeed at 548 knots indicated airspeed (KIAS)==> or ... it will overspeed at 630 mph IAS (statute miles per hour indicated airspeed)As I'd already shown above a number of times, that's the same (speed) after my book!And we all should also know in the meantime - 1 knot = 1 nautical mile per hour. So far, so good.OK - it would also help tremendously if you'd know about what speeds we have in aviation and how they are 'correlated':IAS -> CAS -> EAS -> TAS -> GS (in FS we only have to deal with IAS, TAS and GS)It would further help tremendously if you knew basics about temperature, air density and pressure altitude - for simplicity we assume that:IAS = TAS (at sea level in sim ISA atmosphere conditions => air pressure 1013 mb or 29.92 inches Hg and 15