Why rockets drop their tanks on the way up: the rocket equation and staging
30seconds
Orbit isn't about height. It's about speed: roughly 7.8 km/s sideways, and about 9 to 10 km/s of total speed gain once gravity and air drag take their cut.
The rocket equation says every extra bit of speed costs more fuel than the last, so a single-stage rocket would have to be almost all propellant.
Build your own rocket below. Add stages, shave the tanks, swap the fuel, and see why real launchers drop their empty tanks on the way up.
Deep dive · 4 min
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