posted 03-01-2012 09:17 AM               

Workers remove Apollo-era engines from crawler

For more than 30 years, NASA's two Apollo-era crawler-transporters carried six space shuttles (Atlantis, Challenger, Columbia, Discovery, Endeavour and Enterprise) atop mobile launcher platforms from the Vehicle Assembly Building (VAB) to Launch Complex 39 at Kennedy Space Center.

After traveling 2,190 miles (3,524 kilometers), crawler-transporter 2 (CT-2), which weighs about six million pounds, will receive two new diesel engines and generators so it can be used to carry NASA's Space Launch System heavy-lift rocket, currently under design, and new Orion spacecraft to the launch pad.

Credit: NASA/Kim Shiflett

Above: A crane is used to lift an Apollo-era diesel engine away from crawler-transporter 2 just outside of the Vehicle Assembly Building.

Mary Hanna, the project manager for the crawler-transporters in NASA's Ground Systems Development and Operations Program, is overseeing the upgrade efforts.

"The crawler has to be ready for the new future programs," Hanna said. "It's the only way to get launch vehicles out to the pads, and we're taking time now to do the upgrades so that we're ready." On Feb. 15, in High Bay 2 inside the VAB, NASA engineers and United Space Alliance engineers and technicians prepared the obsolete diesel engines, generators and associated parts for removal. The old engines, which were built in 1964 and installed as original equipment, ran the AC electrical system.

Work began to remove the massive engines in late January when the crawler was moved from the crawler yard into the VAB. About 20 technicians and engineers coordinated efforts to remove the old engines and generators using the VAB's 325-ton overhead crane to lift them out.

The new 1,500 kilowatt power diesel engines, built by Cummins Engines in Minnesota, arrived at Kennedy in mid-December and are being stored in the crawler maintenance yard.

"The new engines are more powerful but they've a smaller footprint," Hanna said.

Credit: NASA/Kim Shiflett

Above: Two new 1,500 kilowatt power diesel engines and generators arrived from Cummins Engines in Minnesota last December.

After the engines are in place, Hanna said, there is a lot of work required to connect the electrical, plumbing and mechanical lines and installation will be completed by mid-June.

The removed engines are being drained, cleaned and readied for transport by flatbed truck to Ransom Road where they will be resold or recycled.

Hanna said crawler-transporter 2 is also undergoing other upgrades and modifications, including 16 higher capacity jacking cylinders; new roller bushings and roller shafts; upgraded electrical power system components; power, control and instrumentation cable replacement; and driver cab controls.

Other upgrades include electrical control systems and programmable logic controller modernization, new instrumentation systems, a new belt pin lubrication system, new hydraulic valves and hydraulic tubing replacement.

Structural shear web augmentation and corrosion control are ongoing tasks, as well.

When all of the modifications have been completed, the crawler will be ready to carry NASA's heavy-lift rocket and other future space program vehicles to Launch Complex 39 for their turn to make space program history.

posted 02-13-2014 02:51 PM               

New roller bearings tested on crawler-transporter 2

The crawler-transporter that will carry NASA's Space Launch System (SLS) and Orion spacecraft to Launch Pad 39B for launch on Exploration Mission-1 in 2017 recently passed the first phase of an important milestone test at Kennedy Space Center in Florida.

The Ground Systems Development and Operations Program completed testing of the new traction roller bearings on crawler-transporter 2 (CT-2), on two of the massive vehicle's truck sections, A and C, in late January. During the test, CT-2 was driven unloaded on crawlerway C, between the Vehicle Assembly Building and Ordnance Road.

Above: Crawler-transporter 2 nears the entrance to the Vehicle Assembly Building on Jan. 31, 2014 at NASA's Kennedy Space Center in Florida. (Credit: NASA/Kim Shiflett)

As the crawler moved along, the left- and right-hand steering was tested in both directions. Workers performed visual inspections of the roller bearing pumps, valves and lines to ensure that the grease injectors worked properly and provided the required flow of grease to the new roller assemblies.

"The temperature of the roller assemblies were monitored and recorded using newly-installed thermocouples," said Mike Forte, a senior project manager with QinetiQ on the Engineering Services Contract. "We were looking for any anomalies and establishing a baseline operating temperature for the new roller assemblies."

Forte said temperature data on the surface of the roller assemblies also was collected using handheld infrared temperature monitoring devices. "We also closely monitored the system for any unanticipated vibrations or noise, which are indications of problems," Forte added.

The test was a collaborative effort that involved about 30 NASA and contractor engineers and technicians from Kennedy and Ames Research Center in Moffett Field, Calif.

Upgrades to CT-2 include 88 new traction roller bearing assemblies, a modified lubrication delivery system, and a new temperature monitoring system that includes 352 new thermocouples.

Above: Crawler-transporter 2 enters the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida on Jan. 31, 2014. Visible are the new roller bearing assemblies that were installed on one side of the crawler. (Credit: NASA/Kim Shiflett)

Forte said subsequent tests will be used to establish permanent operational warning and shutdown limits for a fully-loaded crawler-transporter.

CT-2 returned to the VAB on Jan. 31 so work can continue to install new roller bearing assemblies on the B and D truck sections. Another test is scheduled for November, after installation of the second set of bearings has been completed.

Upgrades to CT-2 are necessary in order to increase the lifted-load capacity from 12 million to 18 million pounds to support the weight of the mobile launcher and future launch vehicles, including the SLS and Orion.

posted 02-24-2015 11:37 AM               

NASA celebrates crawler-transporters first 50 years with test drive

With an eye towards the future, NASA commemorated the first 50 years of its two rocket-carrying crawler-transporters on Monday (Feb. 23) by taking one of the newly-upgraded massive machines out for a test drive to the launch pad.

Crawler-transporter 2, referred to as CT-2, lumbered out of NASA's Vehicle Assembly Building last Wednesday (Feb. 18) to begin the 4.2-mile (6.8 km) trek to Pad 39B at the Kennedy Space Center in Florida. NASA invited members of the media and guests to tour the crawler as it arrived at the pad on Monday to mark the tracked vehicle's first half-century of service.

"This is a historic day witnessing the move of the crawler to Pad 39B," Lisa DeVries, crawler-transporter lead safety engineer for Cummings Aerospace, said. "Thinking back on all that the crawler has done in the last 50 years, from the Apollo program to the space shuttle program, is really incredible."

See here for discussion of the upgrades to the crawler transporters.