Dislodged filter identified as ‘anomaly’ that thwarted LauncherOne mission

This is one conclusion from the ongoing investigation into why Virgin Orbit’s LauncherOne failed to deliver its payload into the mission’s target orbit.

Codenamed ‘Start Me Up’, the first UK mission for Virgin Orbit on January 9, 2023 followed four completed missions on the west coast of the US that delivered 33 payloads to their required orbits. The launch system consisted of a modified Boeing 747-400 fitted with the LauncherOne rocket under its port wing.

The investigation has confirmed that the Virgin Orbit team successfully executed pre-flight preparations, carrier aircraft take-off, captive carry flight, and rocket release. Virgin Orbit added that ignition, first stage flight, stage separation, second stage ignition, and fairing deployment of the LauncherOne rocket were nominal.

Led by space launch veteran Jim Sponnick and Virgin Orbit chief engineer Chad Foerster, the failure investigation team received immediate access to extensive telemetry data collected during the mission from the ground stations in the UK, Ireland, and Spain, as well as systems onboard its carrier aircraft.

Virgin Orbit said the investigation team is utilising a comprehensive fault tree, a very detailed timeline, and several other products to conduct the investigation.

The team has found that from the beginning of the second stage first burn, a fuel filter within the fuel feedline dislodged from its normal position. 

Additional data shows that the fuel pump downstream of the filter operated at a degraded efficiency level, resulting in the Newton 4 engine being starved for fuel. Performing in this anomalous manner resulted in the engine operating at a significantly higher than rated engine temperature.

Components downstream and in the vicinity of the abnormally hot engine eventually malfunctioned, causing the second stage thrust to terminate prematurely. The early thrust termination ended the mission, and the second stage and its payloads fell back to Earth.

In a statement, Dan Hart, CEO of Virgin Orbit, said: “Our investigation is not yet complete; the team is hard at work and we’ll pursue the cause and contributors to wherever the system analysis takes us. However, with many clear clues from extensive data assessment now understood, we are modifying our next rocket with a more robust filter, and we are looking broadly to assure that all credible contributors to mission failure are rooted out and addressed. With those modifications being incorporated on our factory floor, we will proceed cautiously toward the launch of our next rocket, which is well into the integration and test process.”