Not so slight. At airliner altitudes they can differ by 50% or so. IAS is what t...

		TylerE on Feb 19, 2019 \| parent \| context \| favorite \| on: Boeing 787 Reaches 801 MPH as a Jet Stream Packs R... Not so slight. At airliner altitudes they can differ by 50% or so. IAS is what the pilots care about while flying because it’s what matters for aerodynamics (ie stall speed)