 The first flight of the TMA to the ISS occurred on October 29, 2002 with the flight of the Soyuz TMA-1.Because the TMA is limited to three occupants, the ISS was also likewise restricted to that number of occupants, which drastically reduces the amount of research that can be done on board the ISS to 20 person-hours per week, far lower than what was anticipated when the station was designed.With Expedition 20 in May 2009, the crew size of the ISS was increased from 3 to 6 persons with the simultaneously docked two Soyuz spacecraft.