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Crawler-Transporter 2
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Crawler-Transporter 2

NASA's tracked vehicle that carries the Mobile Launcher and SLS between KSC facilities.

Last refreshed: 17 April 2026 · Appears in 1 active topic

Key Question

What machine moves NASA's Moon rocket and how slowly does it travel?

Timeline for crawler-transporter 2

#11 16 Apr

Carried Mobile Launcher 1 from Pad 39B toward VAB

Artemis II Moon Mission: Five open Orion items, no fix dates
#11 11 Apr
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Background

crawler-transporter 2 carried Mobile Launcher 1 from Launch Pad 39B to the Vehicle Assembly Building beginning 08:11 EDT on 16 April 2026. The transit covers four miles at a maximum speed of roughly one mile per hour. Operations paused Thursday evening for crew rest and resumed 17 April.

crawler-transporter 2 is one of two giant tracked vehicles built for Apollo and operated since 1966. It weighs approximately 2,721 tonnes empty and moves on four double-tracked crawlers. Originally used to carry Saturn V rockets to the pad, it has been upgraded multiple times for Shuttle and SLS. It must carry ML-1 to the VAB, wait for Artemis III stacking, then carry the assembled vehicle back to the pad.

With a single functional crawler required to operate, the crawler's availability is a scheduling constraint on NASA's launch cadence. Any unplanned crawler maintenance during the VAB stay could delay Artemis III rollout and push the 2027 launch target.

Common Questions
How does NASA move the Space Launch System to the launch pad?
crawler-transporter 2 carries the fully assembled SLS and Mobile Launcher from the Vehicle Assembly Building to the launch pad at about one mile per hour.Source: briefing
How old is NASA's crawler transporter?
crawler-transporter 2 was built in 1966 for the Apollo programme and has been upgraded multiple times for Shuttle and SLS operations.Source: briefing