NASA's new space capsule has a mind of its own.
- By Michael Klesius
- Air & Space magazine, September 2007
Not far from the front gate of the Johnson Space Center in Houston, obscured by a CVS drugstore and Wendy’s burger joint, stands a nondescript warehouse containing the centerpiece of the new U.S. space program.
Until last year, the building stored old office furniture, cubicle partitions, and Christmas decorations that Lockheed Martin accumulated over a two-decade engineering services contract with Johnson. Today the junk is gone. In its place is a life-size mockup of Orion, NASA’s next space capsule, now being designed.
NASA calls the model a “low-fidelity demonstrator.” That means the mockup, made of two-by-fours covered with PVC laminate, doesn’t really look like a space capsule. It contains no more than a few seats and some modern avionics, but it offers engineers at Lockheed, project partner Honeywell, and astronauts a platform to start integrating hardware and software for a new human-rated space vehicle, the first since the space shuttle was designed a generation ago.
Though the mockup looks humble, the endeavor it represents is anything but. Named for one of the most recognizable stellar formations in the night sky, Orion will take a starring role in Constellation, NASA’s new space exploration program. Constellation aspires to not only put boots back on the moon by 2020 but later land humans on Mars and, eventually, elsewhere in the solar system.
“I've been struck with how something as simple as a wooden mockup and the avionics displays can stir the excitement,” says Marc Sommers, a technician developing Orion’s computer systems. “We take all our new hires on the program and let them crawl through the mockup and fly the simulation. There’s something about being able to touch it and crawl around in it that makes it seem more real, and energizes them for the work ahead.”
There is plenty to do. In August 2006, Lockheed Martin won the contract to design and build Orion—what NASA calls a “crew exploration vehicle”—at a cost of almost $8 billion. The first vehicle to carry humans is expected to reach the International Space Station in 2014 or 2015, depending on budget allocations to NASA.
For engineers like Sommers, something else inside the warehouse stirs excitement: Three briefcase-size computer components sitting on a folding table in the next room. These are Honeywell’s Flight Control Modules, made for use on the Boeing 787 airliner. The three modules will serve as the avionics—the brain—of Orion.
The computer components are at the heart of a question on a lot of curious minds: How will future astronauts fly this wingless, cone-shaped, blunt-bottom capsule?
“The short answer is with a stick,” says Skip Hatfield, NASA’s director of the Orion program, smiling. “The long answer is with lots of automation and
It turns out that future astronauts largely will let Orion fly itself.
INCREASINGLY, IN AND OUT of space programs, computers do the busy work while humans supervise. Operations at the space station, where Orion will dock before heading for the moon and Mars, now feature a mix of human and computer piloting. The space shuttle still docks manually, while Russia’s Soyuz and Progress and unmanned European transfer vehicles will begin using an automated docking system this year. The issue of who is driving depends on the craft and the situation.
For almost all aspects of Orion’s mission, the first option will be to rely on a computer. This will relieve astronauts from the tedium of Apollo-era checklists and flicking switches.
By the time Orion flies, the state-of-the-art flight control systems will have accumulated millions of operational hours in commercial airliners. Before the control modules fly in Orion, they will need to be modified to survive the rigors of space. Engineers will redesign or replace pieces to ensure they can work in a vacuum, be small enough to fit in the spacecraft, and are hardened to withstand the radiation outside Earth’s atmosphere.
Jim Ratliff, NASA’s cockpit team lead, is tasked with coordinating the design of the ship’s control center. He was the project manager for the shuttle’s conversion to a glass cockpit, beginning in the late 1990s, which took a flight deck studded with instruments and consolidated much of it on nine flat panels. Now he’s on to the next generation.
Two of the control computers could fully fail and the third would still fly the vehicle. Not surprisingly, a backup flight computer built with an entirely different hardware system can take over from the main ones in case of emergency.
There is one more worst-case scenario—a complete power failure. For that situation, Orion will carry an emergency system powered by independent batteries that will give the crew enough control to bring the vehicle home safely.
“Our computers won’t talk, but they'll be smarter than HAL—and better behaved,” says astronaut Jim Dutton, referring to the pernicious onboard computer in the 1968 film 2001: A Space Odyssey. Dutton is one of a dozen who are designing the crew exploration vehicle cockpit. He’s no stranger to automation, having accumulated 350 hours flying the F/A-22A Raptor as a test pilot.
“In the Raptor, sensor fusion is a type of automation,” he says. “It relieves the pilot of being a sensor integrator and allows him to focus on his primary job as a tactician. With Orion, all that automation also frees up the pilot and supports his mission of exploration.”
Is there any resistance among fighter-pilots-turned-astronauts to taking Orion’s control systems away from humans?
“There’s no rub there,” says Dutton. “Our goal is to accomplish the mission. Software has a huge role to play. We’re interested in making the leap from the fighter pilot mindset. Spaceflight is exciting no matter what.”
Dutton adds that a lot of pilots came to the astronaut corps from advanced cockpits in the F-15, F/A-18, and now F/A-22, and bring an understanding of automation principles from the military.
“In fact, the shuttle is severely lacking there, which means many pilots have had to take a step back from the modern, upgraded fighter cockpit to fly the shuttle. With Orion, we want to go the other way.”
Future pilot-astronauts also look forward to full redundancy between the two operators, another welcome improvement. “We don’t want to return to the partitioned cockpit as in the shuttle, where only one crew member can reach certain switches,” says Dutton. That configuration sometimes leads to situations in which one astronaut is overwhelmed with tasks while the other can do little to assist.
“In the shuttle, there isn’t enough room for full operator redundancy because of all the switches,” Dutton says. “With Orion, you’ll be able to change displays as if it’s a revolving panel.”
Orion’s flat screens will provide the most striking departure from previous space vehicles. Four flat-panel displays, each about the size of a large desktop monitor, will occupy the instrument panel. These will not be touch screens, as floating objects and astronauts might accidentally bump one. Instead, they’ll be surrounded by manual dials and keypads. Engineers are also considering using a track ball similar to those in fighter aircraft cockpits.
On ascent, the screens will operate with a vague similarity to those in conventional aircraft. One might display artificial horizons and headings; another might display speed, and altitude. The remaining two might show other key parameters, such as the rocket’s electrical or life support systems.
Once in orbit, the screens will switch to new readouts. One or more might show rendezvous and docking information, probably with live video, and with the vehicle’s path, range, and rate of change in closing to, say, the space station or a Mars transfer vehicle.
The other screens may display updated data on the ship’s life support system status and fuel supply.
The screens will use graphic symbols (still being developed) whenever those are deemed the most intuitive way to communicate information such as electronic checklists, malfunction procedures, warning indicators, and motion imagery.
“One of the challenges we’ll face is that the amount of info we’ll display needs to be balanced against the amount of real estate we’ll need,” says Dutton. The team started out with three screens but decided to add a fourth.
Other design aspects are also fluid. Dutton suggests that the reaction control system, which controls steering and attitude, might move from numerical data to schematics.
“Say you lost all your lateral jets. If you only have tables of numerical data, sure, the information’s there, but a schematic may let you grasp it more quickly,” says Dutton.
Orion’s plumbing too may go graphic, with visual interpretations of data on fuel, water, and coolant system fluids. Electrical information may also convert from numbers to shapes and colors, with icons visually wired together on the display, including the status of the solar arrays and batteries.
There will be far fewer knobs and switches on the instrument panel, but it is impossible to drive them out of Orion entirely. Sometimes the old ways work best. “Hard switches will still have their place in this cockpit,” says Dutton, “but they’ll have to buy their way in based on solid rationale.”
THE ORION MODULE will have a busy career. Not only will the new ship take over the job of ferrying astronauts to the ISS and back four years after the space shuttle retires in 2010, but a single vehicle will be expected to make 10 trips to space, where each Apollo module made just one. Orion will also need the capability to remain in orbit without a crew for up to 210 days.
It is built for this rigorous life. The footprint of the capsule, 16.5 feet in diameter, will easily eclipse that of the Apollo command modules, which at their widest spanned only 12 feet, 10 inches. Orion will also be more than twice as heavy as an Apollo command module.
With 380 cubic feet of habitable volume, Orion looks like a more bulky version of an Apollo craft. But it won’t offer the shuttle’s elbow room, which has about five times the space.
“When you’re in the shuttle, it’s like you’re standing behind Dad in the Winnebago,” says Lee Morin, another member of Ratliff’s cockpit development team. Morin, who participated in the shuttle’s glass cockpit makeover, spent 259 hours in orbit aboard Atlantis as a mission specialist in April 2002: “On the shuttle, you get to look over people’s shoulders. Orion’s more like a diving bell.”
To an Apollo crew of three, though, who were crammed into 220 cubic feet, Orion would feel luxurious. And to a Soyuz crew of three, packed into a gestational 141 cubic feet during launch and reentry, it may be considered extravagant. Orbital flights, during which
Orion will have six occupants, could prove…intimate.
The spacecraft will consist of four elements. At the very top will sit the launch abort system, an Apollo-era solution to a worst-case scenario. A thin but powerful rocket with angled nozzles, the abort system would jerk the crew module away from a malfunctioning booster like a cork on a string. In their reclined posture, the astronauts could handle the brief 15-G load.
The crew module, the second element, will carry up to six astronauts to the space station, or four to the moon. It could also work as an unmanned cargo hauler. The design and number of thrusters for the reaction control system are still under analysis; engineers are considering two dozen 100-pound thrusters.
The service module will house a large orbital maneuvering system engine plus, possibly, more reaction control system thrusters. The module would also store electrical equipment and various fluids. It will be the only element that remains attached to the crew module throughout the mission, and will be jettisoned just prior to reentry. Finally, a fairing will connect Orion to the booster stack.
As work progresses, enthusiasm for Orion is growing inside the program, with veteran astronauts eyeing the new hardware with undisguised envy. “The shuttle is so complex, I’m still amazed it works,” says Scott “Doc” Horowitz, who piloted three shuttle flights and commanded a fourth. “Now we’re taking a step back to simpler, robust stuff.”
Horowitz has been running Constellation as NASA’s associate administrator for exploration systems. In July he announced that we would be leaving the agency in October. His has been an important and historic position, but part of him still yearned to be a spaceship jock.
“I sure wish I could fly this thing,” he said.
FLYING ORION is an excercise in computer-astronaut harmony. Skip Hatfield gives the following general scenario of what it would be like to sit in Orion’s cockpit and pilot an orbital flight.
“On the ride uphill, it’s primarily automated,” he says, noting that it’s similar in that regard to the shuttle. “The crew will be monitoring the displays, looking for malfunctions. They’ll be able to select certain actions if needed.”
If a problem is serious enough, the first option is an auto abort system. His group is working on the contingencies for the manual overrides that everyone hopes will never be needed. During descent, the crew will reconfigure the displays to mimic their launch setups, providing an artificial horizon and data on vehicle orientation, speed, rate of descent, heat shield performance, and so on. Should the
astronauts need to override the system, they will be able to fly a manual descent with the stick.
Despite all the automation, Hatfield makes the distinction that the crewmembers, not ground controllers, will operate the vehicle. Even in unmanned cargo configurations, NASA’s vision leans toward that of a deep space probe, in which Orion monitors itself for prolonged periods but can still accept commands from the ground.
Because the physics of reentry haven’t changed, neither has the shape of crew return vehicles. They still have a circular, convex base covered by a heat shield. For most of the flight, the service module will protect the shield, separating just before reentry. On lunar and Mars returns, it will be shed in a maneuver known as a skip reentry. “And no, that’s not named after me,” says Hatfield. “It’s like a stone skipping on water.” At the low point of the maneuver, the service module will separate and burn up in the atmosphere. Meanwhile, the crew vehicle will travel several hundred miles downrange, its reaction control system maintaining the proper orientation for final entry, unobstructed by the service module. “We still don’t fully have the right [heat shield] material yet,” says Horowitz. “But it will be ablative.” In other words, it will mimic the Mercury, Gemini, and Apollo shields, which burned off during reentry.
The shuttle reenters from orbit at about 25,000 feet per second (fps), its leading edges heating up to about 3,000 degrees Fahrenheit—hot enough to melt steel.
When the Apollo modules reached Earth’s atmosphere after a three-day trip from the moon, they were moving at about 30,000 fps. Orion’s velocity will match this on its own lunar return.
But returning from Mars, it will be moving close to 35,000 fps. That speed, about 6.6 miles per second, would take you from Washington, D.C., to New York City in less than 30 seconds. “You’re talking hot,” says Horowitz, referencing a number that starts at more than 4,800 degrees
Fahrenheit. NASA obtained relevant information in January 2006, during the return of Stardust, an unmanned probe that reentered Earth’s atmosphere at about eight miles a second, or 41,967 fps, the highest Earth reentry speed any spacecraft ever attained. Its heat shield offers the best candidate—an advanced combination of carbon and rayon—for Orion’s shield.
But Stardust was less than three feet across. Manufacturing a similar ablator to cover Orion, which is five times larger, might require engineers to join blocks of the material. The seams would need special protection.
Finally, unlike Apollo-era modules and reminiscent of a long-standing Russian procedure, Orion will return to Earth on dry land. In abort mode, it will still be able to splash down in any ocean. But a ground landing is attractive because it eliminates the expense of using Navy ships for recovery. Orion will deploy three reusable parachutes, same as Apollo. Airbags will open just before impact to soften the landing. Orion then will be home, ready to make history nine more times.
“I watched the first Saturn Vs launch as a kid,” Horowitz says. “I was in sixth grade for the first moon landing. I figured, Oh man, by the time I get there this’ll all be over.”
Space veterans like Horowitz share a feeling that what they are doing will bridge the glories of Apollo and an equally exciting future. “What you see here is a vehicle that will be flown by the next generation of explorers,” Horowitz says.
Orion’s first pilots are likely in NASA programs now, the future commanders still just junior astronauts. In the same way, the brains of their spacecraft are now being prepared, so when machine and man are both ready they can explore the solar system together, one launch at a time.