Chunk Of Foam Is Lost, And Insulating Blanket Gap Seen

Space Shuttle Atlantis thundered off Kennedy Space Center Launch Pad 39A on time at 7:38 p.m. ET Friday, boring into blue skies that were a placid counterpoint to the angry thunderstorm that loosed a fusillade of hail two months ago to wreck devastating damage on the Atlantis external fuel tank.

While the launch looked perfect, NASA later discovered two possibly minor problems: a chunk of foam insulation came off a line on the outside of the Atlantis external fuel tank (it’s now uncertain whether the foam hit the orbiter vehicle), and a four-inch gap was seen in the insulating blanket that protects the shuttle vehicle from the blistering heat of reentry.

However, the blanket problem isn’t on a leading wing edge, nose or other area subjected to fiercest heat during reentry, but instead is in an area of lesser heating.

NASA engineers and others began examining whether any corrective action would be required to address the blanket problem.

Clearly, however, there was no wholesale loss of foam insulation from a heavily-repaired area on the external tank, after that hailstorm caused extensive damage there.

Like automatic-weapons rounds, the hail punched thousands of holes in foam insulation covering the fuel tank, damage that had to be repaired over weeks in the Vehicle Assembly Building at KSC, forcing cancellation of an earlier planned March 15 launch.

Questions were raised as to whether all those insulation repairs — the external fuel tank looked as though it was covered with white welts — would hold during launch and ascent, or whether they might cause large chunks of foam insulation to break free from the fuel tank and hit the Atlantis orbiter vehicle.

That’s what happened in 2003, when Space Shuttle Columbia was hit by a chunk of foam that smashed an undetected hole in the leading edge of the orbiter wing. Later, returning to Earth, blistering-hot gases of reentry rushed into the wing and heated structural elements until they failed. Both the ship and crew were lost.

When news media recently asked whether repairs to the Atlantis fuel tank foam insulation might fail, however, NASA leaders said they were confident the repairs would hold, noting that earlier insulation repairs on other external tanks never ripped loose. (Please see Space & Missile Defense Report, Monday, June 4, 2007, page 1.)

Friday evening, when Atlantis lifted off from Kennedy Space Center in a clean burn, those NASA officials largely were proven right.

Cameras on the ground and on the external fuel tank didn’t capture any sign of major foam insulation loss, though small-piece liberation was sighted, and ground personnel held a go-to-the-tape session to replay the launch, looking for any sign of major foam loss.

As well, before docking yesterday with the International Space Station, Atlantis did the now-customary back flip so that space station crew members could photograph various parts of the orbiter vehicle, including its underside, looking for any signs of damage.

At a post-launch news conference Friday night, leaders of the space agency were virtually in orbit with enthusiasm, using terms such as “very good … great … beautiful.”

More importantly, applause came not just from within NASA, but also from Capitol Hill, where top-ranked lawmakers who decide authorizations for NASA were impressed by the stellar flight.

Rep. Bart Gordon (D-Tenn.), chairman of the House Space and Technology Committee (H&T), lauded the NASA team, as did Rep. Mark Udall (D-Colo.) chairman of the HS&T space and aeronautics subcommittee, and Rep. Nick Lampson (D-Texas), chairman of the HS&T energy and environment subcommittee.

Asked about the performance of the heavily-patched external fuel tank, Wayne Hale, space shuttle program manager, joked, “give me more” tanks covered with repairs.

He acknowledged that camera videos showed a bit of foam did break free from the tank.

“We did see a piece come off just after SRB [solid rocket booster] separation,” Hale said. “We didn’t see it strike the orbiter vehicle.”

Even if it had, not only was it relatively small, but the foam piece broke loose “just past the aerodynamically sensitive” period of the ascent, Hale said. That referred to the fact that a piece of foam poses a threat to the orbiter vehicle only when the shuttle has accelerated to a high enough speed, and then only while the shuttle is within a sufficiently dense part of the atmosphere.

NASA experts will examine the external tank closely to see just where and how much foam insulation was lost, and briefers said there probably will be some foam loss observed.

Hale said some foam will be redesigned where it is applied to certain areas on external fuel tanks, such as brackets.

Space Shuttle Atlantis, in its 11- or 12-day STS-117 Mission, will advance construction of the International Space Station (ISS). STS-117 is currently scheduled to land at KSC on Tuesday, June 19.

With the year almost half over, this is only the first space shuttle flight to the ISS, because of the delay caused by the hail damage to Atlantis. That means future planned flights need to go off roughly on schedule if construction on the ISS is to be completed before the shuttle fleet is retired Sept. 30, 2010.

Briefers said each flight will be addressed individually, not rushed because of the flight manifest. To realize that schedule, “it won’t be easy, but not out of the realm of possibility,” William Gerstenmaier, associate administrator for space operations, said.

With Atlantis now having blasted into orbit, for the future, there remain 12 space shuttle assembly flights, two contingency flights and one flight to service the Hubble Space Telescope before the shuttle fleet retires. (Please see page 6.)

With Atlantis having docked with the ISS, crew members will take three spacewalks, or extravehicular activities, beginning today as construction workers building that heavenly house.

The STS-117 mission will deliver and install the 17.5 ton S3/S4 truss segments to go on the starboard side of the space station. This latest addition to the station’s backbone will extend the right side of the truss and includes a new set of solar arrays.

When unfolded, the 240-foot arrays provide additional power to the station in preparation for arrival of new science modules from the European and Japanese space agencies. The crew also will retract a solar array to allow for rotation of the new arrays to track the sun.

This could be a challenge. In prior shuttle missions, astronauts attempting to retract solar arrays long frozen in the deployed position have faced a tough challenge. Spacewalkers at times had to rely on brute force to shove or jostle solar arrays into folding their wings.

With the docking of Atlantis, the space station will welcome its newest resident.

Astronaut Clayton Anderson will join the Expedition 15 crew. He replaces Astronaut Sunita Williams, who has been aboard the station since December.

That may set a record for the time a female astronaut has been in space, and Hale said more records will be broken by future astronauts, including women, as lengthy missions to the moon and Mars are completed.

Williams will return to Earth with the Atlantis crew. Anderson is scheduled to return to Earth on Space Shuttle Discovery, the STS-120 mission, in October.

The Atlantis crew is Commander Rick Sturckow, Pilot Lee Archambault and mission specialists Patrick Forrester, Steven Swanson, John “Danny” Olivas, Jim Reilly and Anderson.