NASA News
National Aeronautics and
Space Administration
John F. Kennedy Space Center
Kennedy Space Center, Florida 32899
AC 321-867-2468
___________________________________________________________________________________________________________
For Release: Oct. 15, 2004
Jessica Rye
Kennedy Space Center, Fla.
(Phone: 321/867-2468)
KSC RELEASE: 79-04
CRAWLER'S NEW SHOES TO HELP SPACE SHUTTLE MOVE TOWARD RETURN TO FLIGHT
NASA’s two crawler transporter vehicles soon will sport new “shoes.” A $10 million project to replace the 456 tread belt shoes, weighing more than one ton each, on both crawlers at Kennedy Space Center begins mid-October.
The shoes are critical for safely transporting the Space Shuttle to the launch pad. Cracks on old shoes can prevent the cleats from moving along the crawlerway and can compromise the structural integrity of the shoes.
Each of the vehicles has eight belts, and each belt has 57 shoes. Most shoes on the crawlers date back to 1965, when the vehicles were built and first put into service for Apollo launches.
Inspections in late 2003 revealed fatigue cracks in many of the shoes, leading to complete replacement of shoes on both crawlers. Crawler transporter No. 2, designated for Discovery's Return to Flight mission to the International Space Station, will receive its new shoes first.
“The crawler transporters are going to be in great shape for Return to Flight and the crawler team is delivering,” said Mark Hamilton, NASA crawler transporter systems engineer. "This is by far the most active maintenance period in the history of the crawlers, requiring continuous heavy equipment crane support and the use of custom rigging and tooling."
NASA and United Space Alliance (USA) crawler transporter systems engineers and USA technicians are repairing the sprockets and rollers on each belt before the new shoes are installed. Welding repair and inspection of some of the sprockets and manufacture of some of the rollers also is being performed at KSC.
The new shoes, each 7.5 feet long and 1.5 feet wide, are being made by ME Global Manufacturing of Duluth, Minn. They arrive at KSC in truckloads of 20 to comply with shipping load limits.
Other upgrades or modifications recently completed on crawler No. 2 include complete electrical rewiring of the motor control center and installation of new driver cabs, mufflers, radiators and ventilation systems. The same work is now under way on crawler No. 1.
Hamilton noted the majority of mechanical crawler parts are unique to the vehicle and are specially manufactured. “We are fortunate that the massive precision components, such as the large drive gear sets and gear shaft bearings, still look new.”
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http://mediaarchive.ksc.nasa.gov/detail.cfm?mediaid=24052
Photo KSC-04PD-2139
KENNEDY SPACE CENTER, FLA. -- In the Crawler Transporter (CT) area, a worker offloads some of the new crawler shoes that arrived from Minnesota. In the background is one of the two CTs. The new shoes were manufactured by ME Global in Duluth, Minn. The CT transports the Mobile Launcher Platform, with the assembled Space Shuttle aboard, between the refurbishment area, the VAB and Launch Complex Pads 39A and 39B. The crawlers have 456 shoes, 57 per belt (8 belts in all). Each shoe weighs 2,200 pounds. The original shoes were manufactured for the Apollo Program. Cracks appeared in the shoes in recent years spurring a need for replacement. The new manufacturer, in Duluth, Minn., has improved the design for Return to Flight and use through the balance of the Space Shuttle Program.
For additional photos on this topic, go to http://mediaarchive.ksc.nasa.gov/search.cfm?cat=16
