A wild ride on NASA's massive flight simulator
The Vertical Motion Simulator trains all comers in capsule landings, helicopter flights, and even bobsled runs. Now it's helping in the design of next-gen lunar landers.
MOUNTAIN VIEW, Calif.--There I was, staking my claim to a pilot's slot in one of NASA's next-generation lunar landers, and to be perfectly frank, I think I'd better not quit my day job.
"I think we probably walked away from that," said NASA aerospace engineer Eric Mueller, after one rough touchdown. It was an overly charitable assessment of my performance. I'd hate to know what he was really thinking.
If you've been paying attention, you're probably aware that there are no current missions to the moon, and so you know that I wasn't actually trying to land there. But I was piloting the same equipment that real-life astronauts have been using to prepare for potential future lunar trips, and so you'll have to forgive me for being a bit disappointed that my skills are likely not up to snuff.
This indulging of my astronaut fantasies was part of a visit last week to NASA's Vertical Motion Simulator (VMS), the world's largest tool for training those whose actual job is to fly lunar landers, space shuttles, helicopters, Joint Strike Fighters, and even bobsleds on the skills and tricks necessary to get their crafts safely to their destinations.
Based in the Aviation Systems Division at NASA Ames Research Center, the VMS offers those who use it six degrees of freedom, including 60 feet of vertical and 40 feet of lateral motion simulation inside a huge, 100-foot-tall chamber that looks like something over which an auto mechanic would salivate. Those "flying" the simulator (see video below) have 20 feet of movement in both in the left and right directions, as well as 4 feet forward and back, and 25 degrees of roll, pitch, and yaw.
Originally opened in 1980 to enable pilots to test-fly helicopters, the VMS is currently being used, among other things, to help NASA get ready for what is likely to be its next great mission: a return to the moon with Constellation, the space agency's long-awaited next-generation program and the followup to the Space Shuttle program.
Over the years, according to Kathleen Starmer, the deputy director of NASA's SimLabs outreach team, VMS has been used by a wide range of private companies and military agencies that have needed to run vertical motion tests, including Boeing, Lockheed, Grumman, and others. And today, even when the simulator is not set up for faux lunar landings, it is in use 100 percent of available time, Starmer said. Those wishing to use it need only show that their project can offer some benefit to NASA, and be able to pony up about $5,000 a day.
But I hadn't come to the VMS to see what it would be like to . I'd come for a shot at Altair, the next-generation lunar lander, and the one that will be the business end of the Constellation program, at least on the surface of the moon.
According to Karl Bilimoria, an aerospace engineer in the VMS program, NASA is now in the process of running its third formal Altair simulation. When reporters aren't being allowed to barely land in the simulator, "pro astronauts," as Bilimoria put it, are coming to Ames and spending full days in the VMS. One reason for that, he said, is that with Altair, the pilots will need to master pinpoint landing accuracy: they'll need to put the craft down within 10 feet of their designated landing sites on the moon, requiring far more precision than what was required of the pilots of the Apollo age.
This is expected to be a difficult task with Altair because one of the design philosophies of the Constellation program will be to shave as much mass as possible off the payload in order to reduce takeoff weight--and save tremendous amounts of money that each additional pound costs to put in space. Bilimoria said NASA hopes to outfit Altair with the smallest possible control jets, a configuration that makes minute control of the landing craft more difficult than was the case with its much sportier Apollo counterpart.
Which would mean, of course, that NASA is trying to offset the loss of some of the brute force control that comes with less propulsion on the lander with state of-the-art electronics: advanced control systems and advanced cockpit displays.
It might not be possible to achieve the kind of landing accuracy NASA wants with the reduced control jet profile, Bilimoria said, but "before we throw our hands up," it will try to solve the problem with technological advances. "We can always squeeze out a little more," he said. "The question is, is it enough?"
To date, Bilimoria said that multiple simulations have shown that technology isn't quite up to the task at hand, and that it could be another year of running tests in the VMS before it's known if the goal is possible. Of course, any return trip to the moon is many years away, but Mueller explained that NASA is doing this work now in order to have the most advanced notice possible if it's going to be necessary to design Altair with larger control jets.
Inside the cockpit, I was strapped in and given some quick instruction (see video below) on how to read the two major digital displays and how to use them in conjunction with a set of joysticks to properly land the craft. The space is set up to resemble what an actual Altair interior would look like, down to the view out the window, and the narrow working space that is partially made possible by having both the pilot and co-pilot stand up straight rather than sit down.
In fact, the Altair cockpit simulator is one of five separate "interchangeable cabs" used in the VMS to mimic different kinds of vehicles, from rotorcrafts to fighters to transport vehicles. Each cab can be set up with conventional aircraft instruments or advanced avionics, depending on the needs of the client using the simulator.
On an Altair pilot's right is what is known as a vertical situation display, which Mueller said is a fairly typical glass cockpit-type display that, for the most part, would be familiar to fixed-wing pilots, and which is new for a lunar lander. The idea, said Mueller, is that this display provides good cues for landing.
On the left side is the horizontal situation display, a newer system that provides Altair's pilots with velocity vectors, and a touchdown display. This system features a set of "bells and whistles" developed at Ames and designed to help the pilot keep a "nice hover" over the landing spot and to improve their hover and descent skills.
And, just to help the pilot with more true-to-life visual cues, there's also a "view" out the front windows, as well as a view from straight down underneath the lander at the ground below.
For someone skilled at piloting any kind of aircraft--even simulated ones in video games--landing the faux Altair is not that hard. The visual cues are extremely intuitive--basically, just keep a little dot in the center of the screen by tapping the joystick one way or another--and it's designed to be fairly simple, in the VMS, at least, to land.
Adding to the realism, of course, is the fact that the cockpit rocks back and forth and left and right, as it would in real life. So if you overcorrect, get ready to tilt the wrong way. Given my lack of skills, I found myself doing that far more than I should have.
Still, in each of my landing attempts, I managed to get the craft onto the lunar "surface," not even crashing once.
To be sure, though, none of the current or future astronauts have to worry much about me being a competitor for their spots on actual moon missions.
Nor would they worry about competition from a CNET colleague who accompanied me to the VMS. As he attempted to fly the lander, his progress was recorded as a long, very squiggly green line on one of the displays, evidence of a remarkable lack of precision.
In the control room, two VMS scientists watched my colleague's progress and shook their heads.
"We've never seen anything like this," said one, of my colleague's roundabout approach to the ground.
"He still hit the pad," said the other. "It's amazing."