The maiden launch of the Space Launch System (SLS) is expected to slip to late 2021 according to a top NASA official.
During a meeting of the Lunar Surface Innovation Consortium at the Johns Hopkins University Applied Physics Laboratory, NASA Associate Administrator Steve Jurczyk discussed the progress of the development of the SLS rocket. Jurczyk explained that the agency was currently targeting to launch the maiden flight of the SLS in mid to late 2021.
Although no official confirmation of this new launch date been released, it is expected to be the latest in a long line of delays.
On August 7, 2014, the development of the SLS Block 1 rocket passed a milestone known as Key Decision Point C, the last before the rocket entered full-scale development. With the completion of this milestone, NASA set an initial launch date of November 2018.
Since then, the rocket’s development has been plagued with delays and rumours that despite the delays, the agency continued to pay the primary contract performance bonuses. These rumours culminated in NASA Office of the Inspector General (OIG) report that heavily criticised how the agency was handling the development of the SLS rocket.
Despite years of delays, it is possible that even the revised mid to late 2021 launch date is overly ambitious.
The first SLS core stage that will be used for the maiden launch is currently being prepared to be put through the “Green Run” static-fire test. This series of tests is an exhaustive review of the stage and includes firing the four RS-25 engines.
As this is the first time the any SLS core stage will be put through its passes, it is not unreasonable to expect that any number of issues could arise. If any do, the stage will be sent back for further development, an outcome that could potentially set the maiden launch back even further.
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