Re: What Happened to the MMU?

In article <45c2c43a$0$24518$4c368faf@xxxxxxxxxxxxxx>,
Jim <me@xxxxxxxxxxxxxx> wrote:
What ever happened to the MMU? Why are they no longer used?

They're in storage, I believe. Basically, because there hasn't been a
good use for them lately.

The MMU was built on the assumption that the orbiter wasn't capable of the
delicate maneuvering needed to dock with a satellite, e.g. for repairs,
especially if the satellite was spinning. But this turned out to be
untrue. In particular, it turned out that the best way to take the spin
off a spinning satellite is to just have spacewalkers in the cargo bay
reach up and grab it. (Moreover, the more complicated plans involving
the MMUs did not actually work terribly well on the Solar Max repair
and the Palapa/Westar salvage.)

That pretty much removed the MMU's reason to exist. For more mundane
tasks like working around ISS, it's easier and safer to crawl along the
structure, or have the arm hold you in position, than to fly free.
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