The first three stages, all powered by solid-fuel, did their job, propelling the vehicle and its cargo over the Atlantic ocean toward space.
- A human error in the integration of the fourth stage seems to be a likely reason for the loss of the Vega mission VV17 from Kourou Monday night, Arianespace said.
"Arianespace expresses its deepest apologies to the clients and the satellite manufacturers involved in this mission", the company said. At that point, the upper stage, called AVUM (Attitude and Vernier Upper Module), correctly detached itself and ignited, in what was supposed to be the first of four consecutive rocket burns.
It would also have placed into orbit Taranis, a French satellite that would have observed extremely bright electrical phenomena in the planet's upper atmosphere.
This is the second launch failure in the last three flights, per Spaceflight Now.
It is unclear what caused the failure, but Arianespace said they were working to determine what went wrong. It appears that cables connected to a pair of thrust vector control actuators were inverted.
The mission would have launched Spain's first Earth observation satellite for the European Space Agency (ESA). Less than 24 hours later, the launch provider published a statement identifying a problem with the integration of the fourth-stage AVUM nozzle activation system.
He blamed quality control and "a series of human errors", for the problem.
Vega's return to flight, delayed by the health crisis and poor weather conditions in French Guiana, took place on 3 September.
The Vega rocket was carrying Spain's first Earth observation satellite, called SEOSAT-Ingenio, and TARANIS, a French satellite created to observe events in the upper atmosphere.
The vehicle impacted an uninhabited area, said Arianespace.