Experimental verification of the possibility of improving the liquid propelant rocket engine performance for the “Vega” launcher upper stage

Successful flight missions demonstrated the high level of reliability and performance of the 4th stage liquid engine developed by the” Yuzhnoye” design bureau for the “Vega” launcher. The obtained specific impulse is 3104.8 m/s which is higher than it was demanded at the initial stage of the development (3094 m/s). Meanwhile, the engine characteristics like mass or specific impulse can be further improved, which was confirmed by experimental investigations. These experimental results and further possible thrust chamber improvements such as implementation of a new radiation-cooling nozzle extension, cooling system redesign and injectors optimization
are discussed and analyzed in the article.