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ESA completes investigation of Vega-C rocket failure

The European Space Agency (ESA) today released its completed investigation of December 2022 launch failure of its Vega-C rocket’s second stage.

One of the recommendations was to implement a (delta-)qualification of the nozzle with a new Carbon-Carbon throat insert material different from that previously used on the Zefiro40, the solid rocket booster of the Vega-C second stage. On 28 June 2023, a static firing test of the modified Zefiro40 engine took place at the test bench in Salto di Quirra in Italy. During the test the engine nozzle suffered significant damages.

ESA Director General Josef Aschbacher has set up an Independent Enquiry Commission chaired by the ESA Inspector General, Giovanni Colangelo, and composed of experts from CNES, ASI, ESA, Arianespace and academia to understand the cause of the test anomaly and propose recommendations.

The Independent Enquiry Commission concluded that in the current design of the nozzle, the combination of the geometry of the Carbon-Carbon throat insert and the different thermo-mechanical properties of the new material caused progressive damage of other adjacent nozzle parts and a progressive degradation eventually leading to the nozzle’s failure.

In other words, the changes implemented based on the initial investigation that was completed in March did not work. The nozzle needs to redesigned, and will also require at least two more static fire engine tests to be certified.

At the moment ESA officials are predicting that Vega-C will resume launches in the fourth quarter of next year, but do not put any money on that prediction.

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.

The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News

One comment

  • Robert Pratt

    An example of how absurd it is that an FAA bureaucrat can know what Space X needs to do to improve a novel cutting edge experimental rocket. It takes real world use and testing to uncover a lot of things and yes, that can be dangerous.

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