WASHINGTON — Members of NASA’s Aerospace Safety Advisory Panel (ASAP) said the agency has done a good job dealing with the loss of three cargo missions to the International Space Station in eight months.

“The cumulative effect of the three cargo mission losses are, in our opinion, significant, but the ISS program was well positioned to mitigate the impacts,” said ASAP member Brent Jett, a former astronaut, at a July 23 meeting of the panel at NASA’s Langley Research Center in Virginia.

Jett said a few key pieces of station hardware lost of those missions “put the ISS in a little bit of a tough position.” That included filtration beds for the station’s water processing system, two of which were lost on the October failure of a Cygnus cargo spacecraft and two more on the June failure of a Dragon cargo spacecraft. Jett said that NASA was able to procure replacement filtration beds that will fly on a Japanese H-2 Transfer Vehicle mission launching to the station in August.

ASAP members noted that the lost cargo did not prevent NASA from continuing to perform research on the station, and that the station returned to a six-person crew with the flight of a Soyuz mission to the station July 22. “The logisticians for the ISS are unsung heroes,” said ASAP Chairman Joseph Dyer.

Jett also said at the meeting that an independent NASA review of the April 28 Progress launch failure, separate from the main Russian investigation, “came to a conclusion that aligned with the Russian findings.” Those investigations determined that oscillations produced by the upper stage engine as it shut down coupled with the structure of the stage itself, causing the stage to break apart. The Progress separated from the upper stage but went into an uncontrolled spin, and reentered in May.