upper stage

American  

[uhp-er steyj] / ˈʌp ər ˈsteɪdʒ /

noun

Rocketry.

1. in a two-stage or multistage rocket, a secondary stage that is activated after the primary or lowest stage has fallen away, and that propels the spacecraft or other payload into orbit or on its intended interplanetary trajectory.

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Etymology

Origin of upper stage

First recorded 1955–60

Example Sentences

In March, Nasa had to roll it back to the assembly building after an interruption in the flow of helium to the upper stage was detected during a fuelling test.

From BBC

Helium is used to pressurise propellant tanks, and any fault in that system could affect the performance of the upper stage engine or the safe draining of the fuel.

From BBC

Inside the VAB, work platforms were raised around the upper stage so specialists could reach valves and plumbing in the helium circuit.

From BBC

The German team managed to measure the pollution the rocket's upper stage emitted in our planet's difficult-to-study upper atmosphere -- the first time this has been achieved, according to a study published on Thursday.

From Barron's

In the early hours of February 19, 2025, the upper stage of a Falcon 9 rocket was tumbling back to Earth when it exploded into a fireball that made headlines from the UK to Poland.

From Barron's