CAPE CANAVERAL, Fla. -- NASA officials are considering what to do about a problem discovered Friday with the two giant crawler transporters that move the space shuttle back and forth between the Vehicle Assembly Building and pads 39A and B at Kennedy Space Center.
The trouble is with the bearings that are part of the crawler system that keeps the entire space shuttle stack level while the transporter moves up and down a gentle incline at the launch pad. It must work in order for the shuttle to safely arrive at the pad.
There are some spare parts available to fix the problem but it's too early to say yet exactly how long it will take to make repairs, said NASA spokesman George Diller. Whether this will affect the launching of shuttle Atlantis as early as Sept. 28 is not known yet.
"We don't know yet how much time we're going to need to deal with this," Diller said Monday.
The worst-case scenario could see the shuttle fleet grounded another month or so while repairs are made, but as of today officials seem optimistic that won't be necessary.
There are 16 "Jacking, Equalization and Leveling" (JEL) bearings on each transporter, two each in eight cylinders arranged on the four corners of a crawler. The system keeps the top of the shuttle straight up and down to within the diameter of a basketball.
Routine inspections on the Apollo-era equipment revealed cracks in some of the bearings and, in at least one case, a bearing that essentially was just taking up space as a collection of parts, officials said. The crawler originally was built 37 years ago.
Diller said there is no question that the broken bearings will be repaired before a shuttle is allowed to be rolled out to the launch pad. However, it's possible the crawlers have been operating fine with the cracked bearings in place.
"After having looked at it we just don't know the reliability so leaving everything alone is not an acceptable risk," Diller said.
Eight spares are currently on the shelf, so any short term repair likely would mean borrowing parts from both crawler transpoters in order to make a single one work.
The first shuttle scheduled to be rolled out to the pad is Atlantis, which during the past weekend saw its cracked propulsion system plumbing flow liners repaired with welds.
"So far they all look good," Diller said.
Ignoring any potential for delay because of the crawler transporter concern, space center workers are scheduled to install Atlantis' three main engines Thursday afternoon and continue to target launch for Saturday, Sept. 28.
Shuttle program managers may choose to delay Atlantis' launch to the following Thursday, Oct. 3, to give workers more time to prepare Atlantis for launch and add a little padding in the schedule to deal with the crawler transporter issue.
Also, a Thursday launch minimizes the overtime expense associated with a weekend lift off.
advertisement
