Ares I-X Slips Into August

Frank Morring, Jr.

NASA managers have decided to position the space shuttle Endeavour on Kennedy Space Center's Launch Complex 39B when sister ship Atlantis lifts off from Pad 39A to service the Hubble Space Telescope, a move that will delay the first flight test of the shuttle follow-on vehicle by three or four weeks.

Endeavour is to serve as a rescue vehicle for the Atlantis crew in case their orbiter is damaged during ascent, since they won't be able to shelter in the International Space Station because it isn't reachable from the telescope's orbit. The shuttle program had considered keeping Endeavour stacked in the Vehicle Assembly Building (VAB) and rolling it out only if post-launch inspection of Atlantis revealed the need for a rescue flight.

That would have freed Pad 39B for the final modifications needed for the Ares I-X flight test, which will send a mostly boilerplate prototype of the developmental crew vehicle through a suborbital flight into the Atlantic to collect data on its flight dynamics and recovery-parachute performance. NASA was holding a July 31 target date for the flight test, providing the pad was released in time to the Constellation Program, which is developing the Ares I crew launch vehicle.

But William Gerstenmaier, associate administrator for space operations, said March 28 the agency has opted to keep its original plan and roll Endeavour to Pad 39B before the planned May 12 launch of the Hubble servicing mission. That choice was driven in part by progress made in converting Pad 39B, where three 600-foot-tall lighting towers have been erected for Ares I, the lone shuttle lightning tower has been removed, and a platform to give workers access to ladders and instruments inside the dummy portion of the flight test vehicle has been installed.

"We were able to get a lot of work done on the pad that still allows us to launch an orbiter off of that," Gerstenmaier said. "So the impact to Ares I-X will be probably three, four weeks maybe."

Atlantis is scheduled to roll to Pad 39A on Tuesday, and Gerstenmaier said NASA would have more information on its overall launch schedule then. The shuttle program was reluctant to hold Endeavour back in the VAB and then rush it out to Pad 39A as the "launch on need" vehicle, with a four-person crew trained to rendezvous with a crippled orbiter.

In the event a rescue is needed, Endeavour would approach Atlantis in orbit and grapple it with its robotic arm. The rescue crew would bring the Atlantis crew to safety by trading out spacesuits until everyone is across. But time would be extremely limited with the seven-person Hubble servicing crew using consumables in the cramped orbiter while Kennedy Space Center scrambles to get Endeavour safely into space.

"We think it's more of our normal plan to have the orbiter out at the pad," Gerstenmaier said. "It gives us a little more robustness from a crew standpoint. And with Ares I-X sitting at the end of July, this isn't too big of an impact to them because we were able to get all the work done at Pad B."

Launch Pad 39B photo: William Hartenstein