Week 21: Landing the Booster

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The Shuttle era proved partial reusability was possible. Decades later, a different approach proved something even more dramatic: landing an entire booster stage back on its tail.

History

Commercial rocketry pushed reusability further than the Shuttle ever did — not just reusing an orbiter, but flying an entire first-stage booster back down and landing it under its own power for reuse on a future flight.

Forces

A landing burn requires thrust-to-weight balanced right around 1:1 — enough thrust to hover or gently decelerate the booster's remaining weight, not accelerate away from the ground.

Math

T = m·g (simple hover condition)

Worked example (metric): a booster with a landing mass of 25,000 kg needs roughly T = 25,000 × 9.81 = 245,250 N of thrust just to hover.

Advances

SpaceX pioneered the first repeated, reliable landings of an orbital-class rocket booster, dramatically lowering the cost of reaching orbit.

Key Date

The first successful landing of an orbital-class booster took place on 21 December 2015.