ESA confirms cause of November Vega launch failure

The European Space Agengy (ESA) has now completed its full investigation of a Vega rocket launch failure in November, and confirmed that the initially announced cause of “human error” was correct.

Engineers had installed cables backwards causing the nozzle in the upper stage to go one way when it should have gone the other.

The press release at the link is a wonder of bureaucratic cover-your-behind gobbly-gook, saying much without providing any concrete information about the corrections imposed. For example, the upper stage structure is built by one company, Airbus, the engine is built by two Russian companies, Yuzhnoye and Yuzhmash, while a fourth company, Avio, supervises the stage’s assembly. The press release makes it a point to not tell us where the error was made by which company, though by vague implication it suggests the error occurred during final assembly by Avio.

If I was a satellite company thinking of buying a Vega launch I would demand a much more straight-forward explanation. Otherwise I’d go elsewhere.

Arianespace: Cause of Vega launch failure “human error”

According to Arianespace officials, today’s failure of their Vega rocket likely occurred because of “human error” in the installation of cables.

Engineers concluded that cables leading to thrust vector control actuators on the upper stage were inverted, apparently a mistake from the assembly of the upper stage engine, according to Roland Lagier, Arianespace’s chief technical officer. The thrust vector control system pivots the upper stage engine nozzle to direct thrust, allowing the rocket to control its orientation and steering.

The cabling problem caused the engine to move its nozzle in the wrong direction in response to commands from the rocket’s guidance system. That resulted in the rocket losing control and tumbling just after ignition of the upper stage engine around eight minutes after launch.

Lagier characterized the inverted cables as a “human error,” and not a design problem.

The next obvious question is the source of the error. The answer was not revealed, I think partly because of the number of contractors involved in building that upper stage:

The AVUM upper stage’s structure is produced by Airbus, and the Ukrainian rocket contractors Yuzhnoye and Yuzhmash supply the AVUM stage’s main engine, which consumes hydrazine and nitrogen tetroxide propellants. Avio, the Vega rocket’s Italian prime contractor, oversees final integration of the AVUM upper stage.

The goal of the investigation that will now follow will be to point that source among these contracts, and how their interaction might have contributed to it.

Arianespace’s Vega rocket fails again at launch

Early today Arianespace’s Vega rocket failed, for the second time in its last three launches, to put two satellites into orbit.

A liquid-fueled upper stage — known as the Attitude and Vernier Upper Module, or AVUM — was supposed to fire four times Monday night to place the Spanish SEOSAT-Ingenio Earth observation satellite and the Taranis research spacecraft from the French space agency CNES into slightly different orbits at an altitude of roughly 420 miles (676 kilometers) .

But something went wrong just after the first ignition of the AVUM fourth stage. “After the first nominal ignition of the last stage engine, an anomaly has occurred, which caused a trajectory deviation entailing the loss of the mission,” said Avio, the Vega rocket’s Italian prime contractor, in a statement. “Data analyses are in progress to determine the causes.”

This is bad new for Europe’s space effort. It will likely but a crimp in the development of their two next generation rockets, the Ariane 6 and the Vega-C, as the upper stage that failed involves all the contractors building those rockets, Airbus and Avio.

The failure of this particular engine also badly damages the future of the two Ukrainian contractors, Yuzhnoye and Yuzhmash, who built it. They have lost all business with Russia because of the war between those two countries, and now have this failure to darken their resume with the rest of the world.

ESA maps out first launch schedule for new rockets

Capitalism in space? The European Space Agency (ESA) today laid out the development roadmap that will lead to the launch of two new rockets, the Vega-C being built by the Italian company Avio, and the Ariane 6 being built by ArianeGroup.

The Vega-C is a more powerful version of the Vega rocket, aimed at capturing the smaller satellite market. It maiden flight is now scheduled for June ’21.

The Ariane 6 is aimed at replacing the Ariane 5, Europe’s big workhorse rocket, but to do so at a lower cost. Its maiden flight is now set for the second quarter of ’22, a significant delay from the previously announced target date in ’21, which itself was a delay from the original late ’20 launch date.

Ariane 6 however has not succeeded in cutting costs enough to match its competitor SpaceX, and thus it continues to have trouble attracting customers, even among ESA’s partner nations that it is meant to serve. These issues have led to rumors that ESA is already looking to either significantly upgrade Ariane 6 (before it even flies), or replace it entirely wit a new re usable rocket.