What it is: True airspeed shows how fast the aircraft is moving through the airmass rather than how much pressure the pitot system senses. As altitude increases and the air gets thinner, TAS rises above IAS even when the indicated speed stays the same.
In practice: During a simulated flight, TAS matters for cruise performance, flight planning and navigation timing. Your aircraft might be indicating 250 knots, yet its true airspeed at higher altitude can be much higher, which affects how quickly you cover distance through the air. Groundspeed then adds or subtracts wind from that figure, so TAS is not the same as the speed shown over the ground on the GPS. Simmers will usually see TAS on the G1000, FMC, EFB or simulator telemetry rather than on a basic analogue airspeed indicator. Developers also use it when modelling climb, cruise fuel burn and performance tables.
Key considerations:
