HOUSTON (AP) – The orbiting Discovery crew started the meticulous inspection of the shuttle’s heat shield on Sunday, looking for any possible damage from liftoff.

Mission specialist Nicholas Patrick maneuvered the shuttle’s 50-foot robotic arm and similarly long boom with cameras and sensors as the exam began on the spacecraft’s right wing.

“Last we heard, they haven’t found anything,” said NASA spokeswoman Brandi Dean, as the crew prepared to scan the left wing – the final step in the inspection.

The thorough sweep included the wings and nose cap for chips and other damage from foam, a procedure made mandatory after the deadly Columbia accident in 2003. The survey began 3:08 p.m. and was expected to last 51/2 hours.

During tests late Saturday, the robotic arm’s latching mechanism was not working automatically, so Patrick manually ordered the arm to grasp the boom. Otherwise, the inspection was without incident. Engineers are examining the camera images in real time and also will review them in greater detail later on.

Preliminary radar reports from Discovery’s Saturday night launch also showed nothing of concern, NASA spokesman Kyle Herring said.

Meanwhile, the other crew members checked on the spacesuits that will be used during the mission’s three spacewalks.

Discovery fired its engines Sunday to raise its altitude to 216 miles above Earth, nearly level with the international space station, where it will dock Monday afternoon.

Then the real work begins.

The first spacewalk on the 12-day mission will involve installing an $11 million addition to the space lab, while the second and third will be for rewiring the station from its temporary power system to the permanent one. The solar power arrays that were brought up during the last mission will be used for the first time after that reconfiguration is complete.

Discovery’s crew will bring home one of the space station’s three crew members, German astronaut Thomas Reiter of the European Space Agency. American astronaut Sunita “Suni” Williams will replace him, staying for six months.

Robert Curbeam will spacewalk three times. Other crew members are commander Mark Polansky, pilot William Oefelein, and mission specialists Patrick, Williams, Joan Higginbotham and the European Space Agency’s Christer Fuglesang, the first Swede in space.

Five of Discovery’s astronauts, including Patrick, are first-timers to space.

They woke up on their first morning in zero gravity to a transmission from Houston of The Beatles’ “Here Comes the Sun,” an allusion by flight control to how the shuttle lit up the nighttime sky during its ascent Saturday.

“Good morning, Discovery. We especially want to thank you for the burst of sunshine you brought into our lives last night. It was an awesome launch,” Shannon Lucid from Mission Control radioed up to the crew.

“It was pretty great for all of us, too,” Polansky responded.

NASA had required daytime launches for the first three flights after Columbia, but now feels comfortable with the improvements made since then.

The Columbia disintegrated while re-entering the at mosphere, killing the crew members.