Determined never to repeat the tragic Challenger launch accident, NASA not only is developing a crew escape system for the space shuttles' replacements; the space agency also has a backup system that could fly astronauts to safety in case of an emergency.
Significantly improving safety is one of the reasons the United States is retiring its three-ship shuttle fleet after five more missions in 2010 to complete construction of the International Space Station.
The shuttles began flying in 1981. Two of the 129 flights ended in disaster, including the Jan. 28, 1986, loss of Challenger, which was destroyed 73 seconds after liftoff due to a leak in one of its booster rockets.
Like the venerable Russian Soyuz capsules still in use today, previous U.S. spaceships had emergency escape systems that could fly a crew module to safety in case of an accident on the launch pad or during the early phases of flight.
The escape system is such an important part of NASA's planned Orion vehicles, that the agency decided to develop a whole new technology should Orion run into problems with the tried-and-true tower-style escape system.
NASA asked its independent engineering and safety center, set up in the wake of the 2003 Columbia disaster, to come up with a crew escape system that eliminated Orion's planned 40-foot-tall, rocket-laced tower that would pull the capsule away in case of a launch emergency.
The tower creates complexity and steering issues to the already complicated engineering challenge of flying NASA's 327-foot tall Ares 1 rocket, Orion's planned launch vehicle.
A small team of NASA engineers and contractors created and tested what it called the Max Launch Abort System, or MLAS. "Max" is a nod to the late Maxime Faget, the designer of the Mercury capsule, the first U.S. manned spacecraft, and to Faget's engineering design philosophy: Build rapidly and test.
With off-the-shelf hardware and a 25-year-old surplus Navy missiles, Ralph Roe, head of NASA's Engineer and Safety Center, and his team built a full-scale composite fairing, crew module simulator and rocket motors to test the alternative design. It successfully flew in July.
"It wasn't widely publicized because it was very complex, and there was a high probability that not everything would work as planned," Tod Palm, MLAS program manager with Northrop Grumman, told Discovery News.
The system worked so well a second test flight to test another launch abort scenario — the July test recreated conditions for an on-pad emergency escape — is under consideration.
"The concept works. It's viable," Roe said. "If we were further along, it certainly would be competitive with the tower design."
A report on the project is expected early next year.
