Science
What If You Travelled at the Speed of Sound?
How far do you go in a few hours at Mach 1, and what is a sonic boom in words?
Mach 1 is not a single speed. It is the local speed of sound, which follows the square root of temperature. Near the ground on a mild day that is about 343 m/s. Up at the tropopause, around 11 km, the US Standard Atmosphere is close to −56 °C and sound is nearer 295 m/s. Multiply by the hours you travel and you have a distance — London to somewhere, or a fraction of Earth's circumference — without pretending this is a jet's fuel burn, ceiling, or route. A sonic boom is the shock you drag when you push air faster than it can get out of the way. Qualitative only: N-wave, ground carpet, why windows rattle. People have done this in aircraft. The hypothetical is you as the payload, not a new aircraft design.
Change this
Results update as you move the controls.
Sound speed follows temperature. 11 km is near the tropopause.
Your result
1,235 km
distance in 60 minutes at Mach 1
sea level
- Local speed of sound
- 343 m/s
- Distance
- 1,235 km
- Earth laps (equator)
- 0.03
- Time for one lap
- 32 hours
- Sonic boom
- qualitative shock / N-wave
1,235 km/h
What does that mean?
At sea level, Mach 1 is 343 m/s (1,235 km/h), using 343 m/s for dry air at 20 °C. In 60 minutes you would cover 1,235 km — 0.03 trips around the equator — if you could hold that speed in a straight line with no fuel story. A sonic boom would be the shock trailing a Mach ≥ 1 path, an N-wave on the ground, not a louder engine. This is not a jet performance sim and not a survival estimate for unprotected air.
At a glance
- Your distance1,235 km
- London–New York ~5560 km5 560 km
- Equator40,075 km
Compare
| Sea level Mach 1 | 343 m/s |
|---|---|
| 11 km Mach 1 | 295 m/s |
| This run | 343 m/s |
Compare scenarios
Pick an altitude, pick a c_s
Sea level uses 343 m/s. Eleven kilometres uses ~295 m/s because the air is cold, not because Mach is magic. Faster true airspeed at the ground for the same Mach is a temperature story. The hours slider is then ordinary distance = speed × time. Earth's equatorial circumference is about 40 075 km if you want a lap count. No wind, no great-circle routing, no Coriolis on the flight plan.
A boom is a shock, not a sound effect
When you travel at Mach 1 you are keeping pace with your own pressure waves, which pile up. Past Mach 1 they form a cone that sweeps the ground as an N-shaped pressure jump — the boom. Intensity depends on altitude, mass, length, and atmosphere. Concorde was loud; a hypothetical you-sized dart would be a different dart. This page will not compute overpressure in pascals. It will say: boom is real, boom is a shock, boom is not thunder from the engine note.
Not a performance chart
Jets that cruise near Mach 0.85 do so for economics and for the drag rise toward Mach 1. Sustained Mach 1 in dense air is expensive. At 11 km the air is thinner and colder. None of that is modelled as thrust, lift or specific fuel consumption. If you wanted walking versus driving, that is another experiment. If you wanted sound itself to be faster, that is the sibling page that scales 343 m/s without moving you.
How we calculated this
Sea-level speed is physics.SPEED_OF_SOUND (343 m/s). Tropopause speed is 295 m/s, a rounded figure for ~216 K in the standard atmosphere (c ∝ √T). Distance = v × hours × 3600. Laps use 2π times WGS 84 equatorial radius. Sonic boom is qualitative. Not a flight-performance integration, not a noise certification.
Go further
A curated rabbit hole from this question. Each link is a real experiment, not a random suggestion.
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