Despite
spending nearly $200 million on spacesuit development over the last eight
years, NASA runs the risk of not having a next-generation spacesuit ready for
testing on the International Space Station before the station is retired, the
agency’s auditors warned.
In
an April 26 report, NASA’s Office of Inspector General (OIG) also warned that
NASA’s declining current inventory of spacesuits, developed in the 1970s, pose
a risk to continued operations of the ISS, particularly if its life is extended
to the late 2020s.
Those
current spacesuits, formally known as Extravehicular Mobility Units (EMUs), are
used for spacewalks outside the ISS. A key element of the suit is its Primary
Life Support System (PLSS), the backpack-like structure that houses equipment
to regulate levels of oxygen and carbon dioxide within the suit and control its
temperature.
NASA
built 18 PLSS units, but only 11 remain available for use today. Of those 11,
four are considered flight-ready today and are on the ISS, with the other seven
in various stages of disassembly or testing on the ground.
The
OIG report warned that further losses of PLSS units, either from launch
failures or because of irreparable damage, could jeopardize NASA’s ability to
perform spacewalks outside the station, which in turn could affect station
maintenance. The agency said that the current supply of spacesuits should be
sufficient to support station operations, but auditors were not convinced.
“NASA
will be challenged to continue to support the EVA needs of the ISS with the
current fleet of EMUs through 2024 — a challenge that will escalate
significantly if Station operations are extended to 2028,” the report concluded.
NASA
has ruled out building additional PLSS units, citing a cost as high as $250
million per unit given their old technology. Instead, NASA has worked on new
spacesuit designs, including those that could support future missions beyond
Earth orbit. Those efforts, though, have suffered a series of problems,
according to the OIG report.
Auditors
were particularly critical of the Constellation Space Suit System program,
which started with a 2009 contract to Oceaneering International to develop a
spacesuit as part of the Constellation exploration program. NASA kept that
contract active until January 2016 despite the cancellation of the overall
Constellation program in 2010, spending a total of $135.6 million on it,
including $80.8 million after NASA cancelled Constellation.
The
report criticized NASA for extending the program, with a new focus on
developing spacesuit technologies, in part because it duplicated work on
another NASA effort, the Advanced Space Suit Project. Technologies being
developed by that project were often more advanced than those being developed
simultaneously by the Constellation suit program, auditors found, even though
NASA spent nearly three times as much on the Constellation contract.
The
Advanced Space Suit Project, though, has had issues of its own, including a
lack of defined destinations for NASA exploration missions that affect
spacesuit design as well as “competing funding priorities” that meant that the
project was funded for only half of the 2016 fiscal year.
That
project is now working on a spacesuit design known as an Exploration EMU, or
xEMU, that will start with a prototype called xEMU Lite to be tested on the
ISS. Current schedules call for that suit to be delivered to the station in
2023 for testing. “This schedule leaves only one year for testing before the
Station’s planned 2024 retirement,” the report stated, but added that
“extending ISS operations beyond 2024 would alleviate this schedule pressure.”
A
third program, the Orion Crew Survival Suit, is a pressure suit designed for
use in the Orion spacecraft and is based on the Advanced Crew Escape System
suits used during the shuttle program. That program, too, is facing schedule
pressures, with a delivery of the suits currently planned just five months
before the current launch date for the first crewed Orion mission in August
2021. That date, though, may be delayed, based on a recent separate OIG review
of NASA’s exploration programs.
NASA
has spent nearly $200 million on those three next-generation spacesuit
programs. “Despite this investment, the Agency remains years away from having a
flight-ready spacesuit capable of replacing the EMU or suitable for EVA use on
future exploration missions,” the report concluded.
Auditors
made several recommendations to NASA, including creating a formal plan for
developing a next-generation spacesuit, performing a trade study comparing
maintaining the current EMU spacesuits versus developing a new one, and apply
lessons learned from existing spacesuit efforts to new designs. NASA accepted
all three recommendations, and plans to have a spacesuit development plan completed
by the end of September.
Source: http://spacenews.com
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