14 DAY TRIAL // The dents discovered in space shuttle Endeavour's heat shield made mission controllers at NASA ask astronauts forming the STS-134 crew to carry out a new inspection of the orbiter's underbelly.
The maneuver will see the crew using a sensor-laden pole to scan the affected portions of the heat shield. This will help determine whether any of the ceramic tiles requires either replacing, or repairs.
Mission managers at the American space agency made the announcement yesterday, May 20. They said that the inspection was scheduled to take place Saturday, May 21, and that it would last about 2 hours.
This procedure is known as a focused inspection, explained during the briefing LeRoy Cain, who is the leader of Endeavour's mission management team. Carrying out the study will provide engineers on Earth with the data they need to finish their analysis.
The orbiter is currently planned to separate from the International Space Station (ISS) on May 29, and to return to the Kennedy Space Center (KSC), in Florida, on June 1. By that time, engineering teams need to clear the heat shield for atmospheric reentry.
During this procedure, the spacecraft reaches speed of up to Mach 25, and its underbelly and wings are subjected to temperatures of thousands of degrees. All heat shield tiles need to be in mint condition in order to avoid disaster.
The first photo survey of Endeavour's heat shield – the one that was carried out on May 17, a day after launch – revealed seven damaged sites, but a particular ding is of interest to NASA, Cain explained.
The area is about 3.2 inches (8.1 centimeters) long and 2.5 inches (6.4 centimeter) wide, and can be found near the shuttle's right-side landing gear door, Space reports. All other damage sites were deemed to pose no risk to Endeavour or its crew.
Cain was also keen on emphasizing that the inspection is just a precautionary measure, which will most likely produce no worrying results. “There's nothing alarming here, and we're really not concerned,” the NASA official explained.
“This is one that we feel pretty confident that we're going to be able to clear once we get some additional data,” Cain added. He also said that the result of the analysis can be ready a day after the inspection. Therefore, NASA should have a clear answer by noon on Sunday.
The photo survey will not interfere with the program set out for the 12 astronauts in space in any way. All three remaining spacewalks will be carried out on time, and the cargo Endeavour is carrying will be unloaded too.