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Convert Calc

Foot per Second to Mach Converter

Enter a value to instantly convert between speed units.

Precision4 dp

1 Foot per Second = 0.0009 Mach (at sea level)

Key Formulas

Kilometer per Hour → Mile per Hour

mph = km/h × 0.621371

Mile per Hour → Kilometer per Hour

km/h = mph × 1.60934

Knot → Mile per Hour

mph = kn × 1.15078

Mile per Hour → Knot

kn = mph × 0.868976

Formula

Ma = ft/s × 8.957066e-4

Aeronautical engineers often measure speeds in feet per second and need to express them as Mach numbers for shock wave analysis and compressibility effects. At sea level standard conditions, 1116.45 ft/s = Mach 1 (speed of sound). This conversion bridges US customary engineering units with the dimensionless Mach scale used universally in aerospace.

Source: NIST SP 811, Table B.8

Frequently Asked Questions

Real-World Examples

A subsonic test aircraft at 500 ft/s = Mach 0.448 — slow transonic research flight.

500 ft/s = 0.448 Ma

Aircraft approaching sound barrier at 1116 ft/s ≈ Mach 1 — transonic effects dominate.

1116 ft/s = 0.9997 Ma

Supersonic flight at 2232 ft/s ≈ Mach 2 — shock waves fully developed.

2232 ft/s = 1.999 Ma

Hypersonic re-entry vehicle at 5580 ft/s = Mach 5 — extreme heating and aerodynamic effects.

5580 ft/s = 5.002 Ma