The site for Space Shuttle Card Modelers
© 2007
   

 

Crawler Transporter

 

I'm proud to release my AXM Shuttle Crawler-Transporter in 1:144 scale. This model has all the features the real one has considering the scale used to make this papermodel. Obviously, some details are missing due to scale. The history of the Crawler Transporter goes back to the Apollo Era. Through the years it has changed very little. The Crawler is part of a project that will be complemented with the Mobile Launch Platform. Both the Crawler and the Mobile Launch Platform will be a perfect match for any AXM Shuttle stack.

The main source of information to make this papermodel comes from the ApolloSaturn website, which shows diagrams with dimensions of the real crawler. Also plenty of NASA photos of the real crawler were very useful for detailing this papermodel. Another interesting site is the Micro Artwork site that shows a very highly detailed crawler but in a larger scale. Their crawler version is a real challenge for the more experienced scale modelers. My model is a very modest representation compared to Micro Artwork's crawler version.

A new website, the Space Shuttle Resource Page, was the source of photos that served to put the details to differentiate the old crawler undercarriage with old mufflers and the new re-designed undercarriage with new exhaust and ventilation systems. Thanks Mark!

Summary of changes:

With the original crawler design made by Marion Power Shovel Company, the crawler made its debut with the Apollo program in the 1960s. The main feature was the stairway access to the Mobile Launch Platform through Side 3. Side 1 had no access to the MLP. Originally, there were no steering arms under the crawler, either. There were also problems with the bearings. In July 1965 during a test at Kennedy Space Center it was determined that the crawler's support bearings could not withstand the loads during turns, therefore modifications were done to the steering hydraulic system.

The crawlers were re-designed for the Space Shuttle in order to carry the MLP from the Vehicle Assembly Building to the launch pad. The re-design brought a new access to the MLP through side 1. Side 3 access was not used due to the MLP position. Throughout the Shuttle program the crawlers did not change much and were exactly as the configuration for the Apollo program. But starting with STS-114 for the Return to Flight mission, the crawlers suffered major modifications. One of the main modifications was to reduce the noise caused by the crawlers. This resulted in the removal of the old exhaust mufflers from the underside of the crawler. Originally, the engine exhaust outlets were located directly under the crawler so operators walking under it to inspect the large trucks were exposed to both noise and diesel smoke. Along with the new upgraded mufflers, the exhaust pipes were extended beyond the end of the crawler, ending up in front of the radiator fan outlets. This greatly increased the distance between the operator and the exhaust outlet noise and diesel smoke. Using the air movement from the radiator fans, the diesel smoke is now blown out from the end of the crawler rather than exhausted under the crawler.

In the past, the ventilation air was drawn in from the sidewalls of the engine/pump room where it would first sweep across the engines before being driven down over the workers and exhausted out through 12 outlets in the floor. The ventilation air is now drawn in from under the crawler through 12 filtered and acoustically treated inlet hoods, thus using the coolest air available.

Now you can build all Crawler variants. Download the files below and enjoy!

 

Source: NASA reduces transporter noise (www.bksv.com)

 

Side 1 view

Undercarriage

 

Side 2 view

 

Side 4 view

Side 3 view

 

Photos show prototype model. Finished model differs slightly in details.

Download Files for all Crawler variants

 

 

Early Apollo Crawler files (1.8 mb)

 

Apollo Crawler files (1.3 mb)

(Can be used for Early Shuttle missions, too)

(As per NASA photos, these files can be used starting with STS-26 Return to Flight)

 

Transition Crawler file

(1 mb) United Space Alliance starts with STS-80

 

 

 

Current Shuttle Crawler main files (4 mb )

 

Alternate Current Crawler file (NASA meatball logo on both sides) (574 kb) Starts with STS-114 and present missions

 

739 kb

Crawler General files:

Crawlergeneral.pdf (2.5 mb)

 

 

 

Crawler Walkways and Access Stairs: allwalkways.pdf (1.4 mb)

 

 

 

868 kb

 

 

 

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