Falcon 9 to orbit: how a rocket works

Description

Falcon 9's published numbers — a 25.6 t first stage with 395.7 t of propellant and 7.6 MN of thrust, a 3.9 t upper stage with 92.7 t behind a 981 kN vacuum engine, a 15.6 t satellite — in kilometres and tonnes. Gravity is Newton's law from Earth's centre 6371 km down; air thins with the real 8.5 km scale height, so drag, max-Q and vacuum thrust share one formula. Propellant leaves the mass every step. Guidance is a controller you can take apart: kick, gravity turn, climb law, cut-off.