How Fast Do Passenger Flights Actually Fly? Airborne and Gate-to-Gate Speed of US Domestic Flights from BTS T-100 Segment Data, 1990–2025

Manufacturers publish cruising speeds for airliners, but no official statistic reports how fast passengers actually travel. We compute two descriptive measures from the Bureau of Transportation Statistics (BTS) T-100 Domestic Segment data: airborne speed, great-circle distance divided by time from wheels-off to wheels-on, and block speed, the same distance divided by gate-to-gate time. Across 8,402,870 scheduled and charter passenger departures in 2025, US domestic flights averaged 423.9 mph in the air and 340.8 mph gate to gate, with 26.1 minutes per flight spent on the ground. Distance explains most of the variation: flights under 500 miles averaged 323.8 mph and flights of 3,500–3,999 miles 528.4 mph, because climb, descent and the 250-knot speed limit below 10,000 ft occupy a fixed share of every flight. Aircraft type matters far less than route length; on the Los Angeles–New York JFK city pair, four aircraft types differed by at most 13.0 mph in the same direction, while each flew 57.5–70.8 mph faster eastbound than westbound, a jet-stream effect that reaches 78.6 mph on San Francisco–Newark. Seasonal variation is small (9.9 mph between March and September). Using July of every year from 1990 to 2025, airborne speed rose from 416.5 to 427.2 mph, driven by a 28% increase in average stage length rather than faster aircraft; block speed rose only 3.1 mph because taxi and gate time grew from 19.5 to 26.6 minutes per flight. A consistent panel of six airlines reporting every July since 1990 confirms the pattern. All inputs are public and every figure in the paper is reproducible from them.