After the release of the conclusions of the Ariane VA241 Independent Enquiry Commission on 22 February, the findings and recommendations were formally presented to a Steering Board on 28 February. The board included Daniel Neuenschwander, ESA Director of Space Transportation; Stéphane Israël, Arianespace CEO; and Alain Charmeau, ArianeGroup CEO.

As stated in the Arianespace press release of 23 February, the direct cause of the trajectory deviation on 25 January was an incorrect value provided to the launcher’s two Inertial Measurement Units (IMUs). Given the special requirements of this mission, the azimuth required for the IMU alignment was 70º but the usual value for geostationary transfer orbit missions of 90º was erroneously used instead. This difference led to the 20º shift to the south in the trajectory from the first seconds of flight.

The underlying reasons for the direct cause have been clearly identified: a need to strengthen the processes for establishing, verifying and approving the specific operational procedures involving the IMU reference frame.

Recommendations to improve processes and quality control have been made. Furthermore, additional recommendations to enhance end-to-end verifications of mission-specific parameters used during the launch campaign were made.

ArianeGroup and Arianespace presented their action plan in response to the Independent Enquiry Commission findings and recommendations.

ESA Inspector General Toni Tolker-Nielsen expressed his satisfaction with the presented action plan, which not only addresses the current issue, but a general plan to improve processes and end-to-end verifications, in particular of the few parameters that are not verified because of their nature during the test on the Functional Simulator before each launch.

Thanks to the action plan of ArianeGroup and Arianespace, the reliability of the Ariane 5 launch system, which already had an outstanding series of mission successes establishing it as a market leader, will be further increased.

The actions will enable the next flight of this heavy-lift vehicle to be made this month.

The Steering Committee mandated the ESA Inspector General to monitor the satisfactory implementation of the action plan of ArianeGroup and Arianespace.

About the European Space Agency

The European Space Agency (ESA) provides Europe’s gateway to space.

ESA is an intergovernmental organisation, created in 1975, with the mission to shape the development of Europe’s space capability and ensure that investment in space delivers benefits to the citizens of Europe and the world.

ESA has 22 Member States: Austria, Belgium, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Luxembourg, the Netherlands, Norway, Poland, Portugal, Romania, Spain, Sweden, Switzerland and the United Kingdom. Slovenia is an Associate Member.

ESA has established formal cooperation with seven Member States of the EU. Canada takes part in some ESA programmes under a Cooperation Agreement.

By coordinating the financial and intellectual resources of its members, ESA can undertake programmes and activities far beyond the scope of any single European country. It is working in particular with the EU on implementing the Galileo and Copernicus programmes as well as with Eumetsat for the development of meteorological missions.

ESA develops the launchers, spacecraft and ground facilities needed to keep Europe at the forefront of global space activities.

Today, it develops and launches satellites for Earth observation, navigation, telecommunications and astronomy, sends probes to the far reaches of the Solar System and cooperates in the human exploration of space. ESA also has a strong applications programme developing services in Earth observation, navigation and telecommunications.

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