[Results of operator's work during space flight (experiment "pilot") under different work-and-rest cycles]

The correlation between operator's job quality and crew work-rest cycle (WRC) aboard the International space station was studied. The experiment involved 10 Russian members of ISS missions 17-24 at the age of 35 to 51 yrs. Mission duration varied from 163 to 200 days, averaging 180 days. Each cosmonaut carried out several "pilot" test sessions. The number of sessions per mission ranged from 4 to 6. The procedure consisted of simulating manual operation of transport vehicle Soyuz on the stages of hang-up, berthing and docking with the ISS. Objective job quality parameters were accuracy of the Soyuz and ISS relative motion control and time for completion which actually characterized work rate. WRC intensity was judged by the data of monitoring at the Moscow Mission Control Center. The results lend support to the dependence of operator's efficiency on WRC. In operators aimed at the highest accuracy this dependence manifested itself in work rate parameters; work accuracy but not rate was more WRC-dependent in operators aimed at doing their job fast. In other words, WRC intensity impacted mostly those job qualities that operator considered to be of secondary importance.