Crew preps for spacewalk; advisory council warns of gap in ISS access
With SpaceX’s Dragon cargo ship securely attached to the International Space Station (ISS), and cargo being transferred, two members Expedition 48 are gearing up for a spacewalk, set for August 19. The spacewalk will see the installation of the International Docking Adapter (IDA).
Additionally, on August 4, Expedition 48 Commander Jeff Williams celebrated his 500th cumulative day in space over four missions. He is set to break Scott Kelly’s record of 520 days by August 24. By the time Williams returns to Earth on Sept. 6, he will have accumulated more than 533 days off the planet.
Before Williams break’s Kelly’s record, he and Flight Engineer Kate Rubins will perform an Extravehicular Activity (EVA) to install IDA-2. Once complete, the station will be able to receive commercial crew vehicles such as SpaceX’s Crew Dragon and Boeing’s CST-100 Starliner.
Suit preparation began early last week when a new spacesuit was unloaded from inside Dragon. Extravehicular Mobility Unit (EMU) 3006 was removed from the spacecraft and taken inside the ISS for on-orbit operations. This suit, however, will not be used in the mid-August spacewalk as it is being checked out as a viable spare. The previous spare suit, 3005, is being returned to Earth inside the CRS-9 capsule.
On July 27, the station’s robotic Canadarm2 was commanded to ungrapple from CRS-9, where it had been since Dragon’s arrival, and move its Latch End Effector (LEE) to the Pressurized Mating Adapter 2 (PMA-2) in order to inspect the docking port. This location is where IDA-2 will be installed.
With PMA-2 inspections complete, a “go” was given for IDA installation. The arm’s LEE was then moved to Dragon’s trunk in a pre-grapple position in advance of IDA installation.
July 28 saw the crew resize EMA 3003 and 3008 to fit Williams and Kate, respectively. Each EMU is modular and can be adjusted for an individual astronaut in order for them to fit securely. It is necessary to do this prior to an EVA because astronauts’ bodies stretch in space. This is due the lack of gravity compression on the spine.
Last Friday, the crew inspected the Simplified Aid for EVA Rescue (SAFER). Additionally, the airlock was cleaned out, and some items were relocated to the CRS-9 Dragon in order to support the spacewalk.
Over the weekend, the two suit’s lithium ion batteries were recharged. Throughout the beginning of this week, equipment needed to support the spacewalk, such as tethers, were inspected for damage.
Preparations will continue off-and-on for the next week-and-a-half with science and cargo transfer being priorities as well.
Regarding the Commercial Crew Program, which will restore U.S. human launch capability, at a July 26 meeting of the NASA Advisory Council, some members talked about a potential “gap” in crew access to the ISS should the two companies fail to be certified by the end of 2018.
According to a report from Space News, Wayne Hale, interim chairman of the council’s human exploration committee, told the council that while both companies are scheduled to have their spacecraft ready in 2018, there is “very little margin” in those schedules.
“Human spaceflight development programs invariably suffer schedule slips due to their technical complexity, and integration of commercial providers into government service adds further obstacles,” Hale told the council. “It’s therefore prudent to assume delays in the post-certification missions from the schedule.”
Right now, NASA has purchased seats inside the Russian Soyuz spacecraft through the end of 2018 – at a price of over $80 million per astronaut. This includes a couple landings in 2019 as well.
NASA needs to arrange flights in the Soyuz two or three years in advance as there is a long lead time to procure seats. As such, according to Space News, Hale said a decision must be made by the end of 2016 to guarantee access to the ISS in 2019.
As the schedule holds right now, SpaceX is expected to have a certification review in October 2017, while Boeing is expected to have theirs in May 2018. This will only come after each company completes their test flights, both uncrewed and crewed, successfully.
NASA has ordered four post-certification flights from these companies (two from SpaceX and two from Boeing), but no date has been set for these crew rotation missions. While the first are expected to fly in 2018, there is always a possibility of a slip into 2019.
“The future availability of Soyuz is not certain,” Phil McAlister, director of commercial spaceflight development at NASA, said at the July 26 meeting. “We’re going to have to continue to monitor that and see whether we’re going to need, and if we can purchase, more Soyuzes.”
Derek Richardson has a degree in mass media, with an emphasis in contemporary journalism, from Washburn University in Topeka, Kansas. While at Washburn, he was the managing editor of the student run newspaper, the Washburn Review. He also has a website about human spaceflight called Orbital Velocity.