On 14 May 1981 Romania was sending the first cosmonaut in space, becoming the 11th country in the world to do this. Dumitru-Dorin Prunariu became the 103-rd person in the world that achieved this milestone.
The launch took place on 14 May 1981 at 20:16 Romanian time, with the Romanian cosmonaut Dumitru-Dorin Prunariu and the Russian commander Leonid Popov on board. After 8 minutes and 50 seconds, the spacecraft separated from the last stage. 28 hours passed before the coupling with the orbital station, during which the cosmonauts made two orbital maneuvers, tested the systems of the ship and also had some time to rest. The Soyuz 40 spacecraft coupled with the Salyut 6 orbital station on 15 May at 21:50 Romanian time.
Together with the station crew — the pilot-cosmonaut Vladimir Vasilievici Kovalionok, seconded by the pilot-cosmonaut Victor Petrovici Savinîh — they ran a number of 11 Romanian scientific experiments during the flight, four experiments from flight partners and several other experiments that were ongoing from other Intercosmos crews.
Among the Romanian experiment was:
- the NANOBALANTA experiment proposed by ITIM focused on the stability of the protective layers of silicon dioxide deposited on the optical components of the space station (windows, lenses, solar cells, etc.) under the influence of the cosmic environment (radiation, solid microparticles, temperature variations). For this purpose, the deposited protective layer was used as a resonator and the changes were monitored through the effect on the resonator frequency.