In Space Shuttle Program, 14 Crew Members So Far Died Over 17 Years In Two Disasters; NASA, Lockheed, Learning From Tragedies
Reightler Says New System Eliminates Threats From Ice And Foam Hitting Crew Capsule, Danger Of Remaining Linked To Exploding Rocket, And Problems Of Having Crew And Heavy Lift In One Single Vehicle
HAMPTON, Va. — The next-generation Orion-Ares manned U.S. spacecraft will be inherently safer in multiple ways, compared to the existing space shuttles that have risks built into their design, according to Kenneth S. Reightler Jr., a former astronaut.
He is a vice president with a Lockheed Martin Corp. [LMT] unit, Lockheed Martin Space Systems Co., which leads the Orion crew-carrying space capsule development program. Others are developing the Ares rocket that will lift Orion to space.
Thus far, 14 shuttle crew members have died in two separate space shuttle accidents over 17 years, first in 1986 when Space Shuttle Challenger suffered violent solid rocket booster disintegration attributed to faulty O-rings, and then in 2003 when Space Shuttle Columbia disintegrated during reentry.
That disaster was caused by a large chunk of foam ripping loose from the external fuel tank and striking the leading edge of a wing on the orbiter vehicle carrying the crew, punching a hole that later, during an attempted return to Earth, permitted searing hot gases of reentry to heat the wing until it suffered structural failure.
That can’t occur on the Orion crew exploration vehicle — by design, Reightler told Space & Missile Defense Report, speaking at NASA Langley Research Center, where later he delivered a lecture on the 50th NASA anniversary.
“The Orion-Ares system was intended to be safer,” he said, thanks to the fact that engineers managed to “overcome some of the problems that we have seen on the shuttle.”
While it always is true that there is no such thing as fully safe space travel, and that fatal accidents always are possible, Orion will be safer in many ways than the shuttle, he said.
For example, the Columbia disaster was possible because the orbiter vehicle had an external fuel tank that towered over the crew-carrying spacecraft. And because the tank carried extremely cold hydrogen and oxygen, the tank had to be insulated to lessen — not totally eliminate — chances it could become covered with dangerous chunks of ice prior to launch.
That design posed a threat of ice and/or foam insulation ripping loose from a high point on the external tank during a shuttle ascent to space, perhaps striking the orbiter vehicle and damaging it.
But with Orion, the crew-carrying space capsule will be mounted at the very top of the Ares I rocket, similar to the tried-and-proven arrangement in the Apollo moon missions. Therefore, there won’t be any chance of ice or insulation striking the capsule.
One reason the space shuttle external fuel tank must be so large is that it combines both crew-carrying and cargo-carrying capabilities in a single vehicle. The shuttles had to carry immense, and immensely heavy, structural components into space for construction of the $100 billion International Space Station, requiring an enormous amount of fuel that only could be carried in an external tank.
In contrast, Reightler noted, the Orion-Ares program separates the crew-carrying task, which uses a slimmer Ares I rocket, from the heavy-lift work using a far larger Ares V rocket.
So that resolves the Columbia-type problem.
Not Another Challenger Disaster
Further, the Orion spaceship will address the Challenger-type danger.
Here, the space shuttle was set to launch in atypically cold weather from Kennedy Space Center, Fla. The cold caused O-rings sealing segments of the solid rocket boosters to become inflexible. So in the seconds immediately after ignition and liftoff, fuel escaped through failed O-rings and ripped the boosters and the shuttle apart. Among crew members who died was payload specialist and Teacher in Space participant Christa McCauliffe. It was not until last year, more than two decades later, that her backup teacher/astronaut, Barbara Morgan, flew on Space Shuttle Endeavour on a mission to help build the space station. And even then, chunks of ice or foam damaged Endeavour during ascent. (Please see Space & Missile Defense Report, Aug. 13, 2007.)
Here again, Orion will incorporate design changes to diminish dangers, Reightler said.
First, O-rings ever since Challenger have been carefully checked, and low-temperature launches discouraged.
But much more, if there were to be another near-explosive catastrophe that would rip apart a rocket, a launch abort system would instantly whisk the crew and Orion capsule up and away to safety, Reightler noted. (Please see Space & Missile Defense Report, March 17, 2008.)
The abort system features a small rocket mounted on a frame attached to the Orion capsule. At the first sign of a problem with the Ares rocket, the abort system would trigger, with no need for the crew to realize there is a problem and take action.
Rather, Orion would separate from Ares, and the rocket would zip the space capsule up and away from the danger.
Other new safety features on Orion will include far greater simplicity than the shuttles, Reightler noted. The shuttle has been described as the most complex machine ever built, and it certainly is complicated.
As well, Reightler said, Orion will involve a great deal of redundancy, with backups in case systems fail.
“We try to reduce complexity that we see in the shuttle today in terms of the way you have to maneuver the vehicle, and things like that. But primarily, having the launch abort system, the simplicity of the design, the robustness, and … having a capsule on the top of the rocket, lends itself to a safer vehicle,” he said.
Another factor making the future space vehicle safer looks back to the past, taking proven designs from the Apollo program and updating them for Orion, Reightler observed.
“That kind of goes into the whole idea of making it simpler, making it more robust, having a capsule that has the ability to have a ballistic reentry,” he said, “unlike a winged vehicle [such as the shuttle orbiter vehicle] that [has] an active control system to maintain attitude.”
But overall, Orion relies heavily on known technology that has performed well in countless space missions, including seeing what worked and what didn’t in the space shuttles, he said.
The Orion program is “relying on a lot of known technology, or having technology that’s derived from space shuttles, where we have a lot of experience in manufacturing it, maintaining it, operating it,” he explained.
NASA made clear to him as a contractor that the space agency wishes to use the rare opening of designing a new spacecraft to eliminate the design flaws that have caused tragedies in the past, and that reducing dangers facing astronauts is a main focus of his job.
“Program management is about managing risk,” he said. “From the first meeting I had, it was clear that was foremost on people’s minds — identifying and then managing risks.”
Because he has faced those dangers in flying to space, he said that “as an astronaut, I think we get tremendous confidence … and satisfaction” in attempting to bring some margin of safety to space travel.
Is The Moon Deja Vu?
Orion won’t have its first manned flight until 2015 or thereabouts, and that will just go to low Earth orbit. Then it will have its first flight to orbit the moon, and send the lunar lander Altair to the surface, in 2020. The United States won’t go to a new and undiscovered heavenly body — Mars — until the 2030s.
Critics have asked why it is taking roughly a decade and a half to return to the moon, which NASA already has visited, when the Apollo program landed a man on the dusty surface in 1969, just eight years after President Kennedy called for a lunar expedition, and at that time no one ever had made a trip to the moon. Also, critics say since the United States alone among nations has placed men on the moon, why replicate the feat? Why not instead push out the boundaries of the final frontier and go directly to Mars, without revisiting the moon?
We asked about this, and Reightler said there are sound reasons for moving ahead in stages, rather than going for broke, attempting to go to Mars immediately.
To be sure, he said, it is a strength of the United States that it has an open society with open debate on issues such as this, “before we finally commit to a plan.” But once a plan is in place, then people should get behind the plan and make it a reality, he said.
Reightler said he firmly is on the side of a phased move into the void of space, beginning with all that has been learned about extended human presence in space on the space station.
“I think there is tremendous benefit in having the opportunity to first of all use the International Space Station to develop a lot of our technology and prove a lot of our concepts, and get more experience with humans in space for long duration,” he said.
Similarly, there is huge value in being able to use the moon as a proving ground, “because it definitely is a bigger challenge … being and operating on the surface of an object like the moon, over and above what it takes to live on the space station.”
Another key point that ought to be emphasized in this debate, he said, is that the moon is nearby at roughly 240,000 miles, which he noted is but three days from planet Earth should something go awry with the space capsule or if a crew member suffers a medical emergency. On one mission, Apollo 13, problems did arise, but it didn’t require even a week to get the stricken space capsule back to its home planet.
Mars, in contrast, is about half a year distant from Earth, in total about a two-and-a-half year round-trip journey “with current technology,” he noted. (Please see separate story in this issue on a faster, better way to reach Mars.)
In designing Orion, because it is similar in structural concept to Apollo, with a capsule atop a rocket, NASA and Lockheed are attempting to use Apollo gray power (take that two ways: gray-matter intellect, and the experience of older people).
“We are definitely taking advantage to the degree we can, of knowledge of people who worked on Apollo, who flew Apollo, who operated Apollo both in the ground control center,” and “the folks [who] did a lot of the early planning logistically for those missions. We are definitely trying to tap into that experience as much as we can,” he said.
He has his own experience in space as well, as a pilot aboard the STS-48 Mission of Space Shuttle Discovery in 1991 to deploy a satellite, and also as pilot on the STS-60 mission of Discovery in 1994, the first shuttle mission with a Russian crew member.
Sadly, some of the Apollo history has been lost in the mists of time and can’t be retrieved, Reightler said.
“There certainly [have] been some things lost, I think, from the human perspective, in terms of data and archives. It is not a complete record,” he said. Still, “there is a lot of good information” for the next-generation spaceship development effort to harvest from the titanic effort the United States made more than a third of a century ago.
Some fascinating and compelling stories have come from that era, such as a recent movie, “The Dark Side of the Moon,” he said, with riveting tales and “some emotion – – things you don’t typically see in astronauts.”