The crawler is what transports Shuttles and rockets from the rocket assembly building to launch pad.

When the crawler reaches the launch pad, how is the Shuttle transferred from the crawler to the pad?


1 Answer 1


The crawler carried the shuttle, boosters, and external tank which were mounted on the Mobile Launch Platform (MLP).

enter image description here

Image source: Universe Today

The crawler went to the pad, put down the MLP at the launch pad, and crawled away.

This left the MLP, shuttle, boosters, and external tank at the pad.

When the shuttle launched, only the MLP remained.

The crawler came back and got the MLP, and took it to the Vertical Assembly Building so that the stack could be built on it for the next flight.

When the MLP is not on the crawler, it sits on support posts, as shown in this photo where the MLP is at a parking site.

enter image description here

(personal photo)

The crawler has a Jacking-Elevation-Leveling (JEL) system that allows it to raise and lower the MLP and anything mounted on it. It also keeps the MLP level when the crawler is climbing the slope to the pad.

To pick up the MLP, the crawler lowered the JEL system, drove under the MLP sitting on the support posts, then raised the JEL system to lift the MLP off the support posts. The reverse happened when the crawler was putting the MLP down on the support posts.

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    $\begingroup$ Don't want to step on @OrganicMarble toes so just a comment here: these might be useful: youtu.be/5caQPiRBCAA?t=460 they talk about the JEL (Sorry its SLS, STS), and just a general move video youtu.be/kKSC0J1ehFg (I don't know if its a no-no but Spaceflight forum has a crawler thread..?) . Would love to see a simple animation though.. $\endgroup$ Commented Nov 9, 2022 at 16:15
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    $\begingroup$ @blobbymcblobby thanks for the links! The ntrs link is in the answer already. $\endgroup$ Commented Nov 9, 2022 at 16:17
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    $\begingroup$ @OrganicMarble Sorry, had a hundred tabs on the go and was copy and pasting hurriedly! removed it before the 5minute limit! $\endgroup$ Commented Nov 9, 2022 at 16:21
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    $\begingroup$ someone made an animation, but skipped over the use of the JEL system: youtu.be/oMeXcBk1x-c?t=329 $\endgroup$ Commented Nov 9, 2022 at 16:32
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    $\begingroup$ @blobbymcblobby cool. I like the animation of the orbiter lift. It even shows how it had to be rotated to get the wings to fit through the hole. $\endgroup$ Commented Nov 9, 2022 at 16:34

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