Very impressive! It sounds like the test went fine here are the ESA comments:
Today’s hot firing of the P120C solid-propellant motor at Europe’s Spaceport in French Guiana proves its flight-worthiness for use on Vega-C next year and on Ariane 6 from 2020.
This marks an important milestone in the development schedule of Europe’s new-generation launchers, designed to boost our autonomy in the space arena, and maintain Europe’s global competitiveness.
The test lasted 140 seconds with the motor delivering a maximum thrust of 4650 kN, simulating the complete burn time from liftoff and through the first phase of flight.
No anomalies were seen and the performance met expectations, though full analysis will take several months.
The P120C is 13.5 m long and 3.4 m in (44.3 ft by 12.8 ft) diameter and is made using a carbon composite material and built in one segment. It will replace the current P80 as the first stage motor of Vega-C. Two or four P120Cs will be strapped onto Ariane 6 as boosters for liftoff.
This test was a collaboration between ESA, France’s CNES space agency, and Europropulsion under contract to Avio and ArianeGroup.
The next static firing will occur at the end of this year with the P120C qualification motor.