|Country of origin||Italy|
|Used on||Ariane 6, Vega-C/E|
|1 stage – P120C|
|Length||11.7 m (460 in)|
|Diameter||3.4 m (130 in)|
|Empty mass||11 t (24,000 lb)|
|Gross mass||154.6 t (341,000 lb)|
|Propellant mass||143.6 t (317,000 lb)|
|Thrust||4.5 MN (1,000,000 lbf)|
|Specific impulse||278.5 s|
|Burn time||132.8 s|
P120 is a solid-fuel first-stage rocket motor in development As of April 2019[update] by Avio and ArianeGroup through the joint venture Europropulsion on behalf of European Space Agency for use on Vega C and Ariane 6.
The production of P120C was originally planned to be shared by the main Avio facility in Colleferro, Italy and by OHB-owned MT Aerospace facility of Augsburg, Germany. At the 17–18 May 2018 meeting of the ESA launcher program board in it was decided the production of P120C will be done in its full capacity in Italy. Mt Aerospace will instead produce turbo pumps for the upcoming Ariane 6 rocket originally awarded to Avio.
The first test firing of P120C was carried out on 16 July 2018 on the BEAP test bench at the Europe's spaceport Guiana Space Centre in Kourou, French Guiana. The test lasted 140 seconds with the motor delivering a maximum thrust of 4.65 MN (1,050,000 lbf), simulating the complete burn time from liftoff and through the first phase of flight. No anomalies were seen and the performance met expectations.
On 28 January 2019 a second test firing of 135 seconds at the Guiana Space Centre qualificated the P120C rocket motor for flight.
The second qualification model of the P120C solid rocket motor, configured for Ariane 6, completed its hot firing on 7 October 2020 at Europe's Spaceport in French Guiana.
The P120C rocket motor is derived from the first stage of the Vega rocket P80. Like its predecessor, the structural casing is made of carbon fibre, which is built from pre-impregnated epoxy sheets through filament winding and automatic fabric deposition. It will contain 143.6 tons of HTPB 1912 solid propellant composed by 19% of aluminum powder, 69% of ammonium perchlorate with 12% of hydroxyl terminated polybutadiene binder.
It takes 3,500 km (2,200 mi) of carbon fibre, wound over 33 days in a climate controlled room held at 21 °C to make the motor's 25 cm (9.8 in) thick walls. The finished launcher will carry 143 tonnes of solid fuel and produce an average of 4.5 MN of thrust.