Pogo oscillation is a severe, self-amplifying resonance that occurs when surges in rocket engine thrust cause the vehicle structure to compress and stretch. This flexing alters the pressure in the propellant feed lines, which in turn feeds the engine unevenly, creating a feedback loop of violent thrust variations. If not dampened by gas-filled accumulators in the plumbing, these intense vibrations can tear a launch vehicle apart or incapacitate the crew.
Telemetry shows we had some mild pogo on the center engine right before MECO, but the accumulators absorbed the worst of it.
The name comes from the way the rocket bounces longitudinally along its flight path, exactly like a person on a pogo stick.
Also heard as
- pogo oscillation
- pogo effect
Related terms
max Q
The point during a rocket launch when aerodynamic stress on the vehicle is at its absolute highest.
MECO
Main Engine Cut-Off is the moment during a rocket launch when the primary engines are commanded to shut down.
Launch vehicle
A rocket or other system used to carry a payload from the Earth's surface into space.