Riding Rockets

There were other simulators besides the SMSes. Astronauts trained for spacewalks in an enormous indoor swimming pool, the Weightless Environment Training Facility (WETF). The pool contained replicas of the shuttle airlock, cargo bay, and payloads. We dressed in 300-pound spacesuits and were craned into the water, where scuba divers ballasted us with lead until we floated at a fixed depth. This “neutral” buoyancy provided a fair replication of what occurred on real spacewalks, where a push on a tool would result in an equal and opposite reaction. The WETF facilitated the design of tools, handholds, and foot restraints for spacewalkers, all necessary to complete weightless work.

There was also a simulator for MSes to acquire skills with the Canadian-built Remote Manipulator System (RMS). The Manipulator Development Facility (MDF) contained a full-scale mock-up of the shuttle cargo bay (60 feet long and 15 feet in diameter) and a fully functional 50-foot-long robot arm. Huge helium-filled balloons served as weightless payloads. MSes would stand in a replica of the shuttle’s aft cockpit, look through the aft windows, and operate the robot arm controls. We would lift the balloons from the cargo bay and/or stow them in the bay in simulations of orbit activities.

Robot arm operations were challenging. A camera at the end of the arm transmitted images to a screen in the cockpit. MSes would look at these images and simultaneously use two hand controls to bring the arm’s business end to a successful grapple with the target. Using these hand controls while tracking a moving target on a display screen (how we would grapple a free-flying satellite) was like patting your head and rubbing your stomach at the same time. It required lots of practice. To assist us in developing tracking skills, the engineers provided a moving target that hung from the ceiling of the building.

In one of my MDF sessions, I employed my newly acquired tracking skills to tease Judy Resnik. I knew from the schedule that she was next up for the training and watched for her to enter the building. When she did, I maneuvered the end of the robot arm so as to track her with the camera at its tip. She glanced up and saw the huge boom dipping and swaying and twisting to her every turn and knew exactly what I was doing. She stopped, and I flew the arm outward as if it were reaching for her, then slowly tilted the wrist joint so the camera scanned her body from head to toe. When she entered the cockpit, she smiled and said, “You’re a pig, Mullane.” I smiled back and pretended not to understand, but of course she was right.

While I eagerly looked forward to SMS, WETF, and MDF simulations, there was one simulator I could have done without…. NASA’s zero-G plane, nicknamed “the Vomit Comet.” This was a modified Boeing 707 aircraft. Large sections of seats had been removed and the interior surfaces padded. After taking off from Ellington Field, the pilot would steer for the Gulf of Mexico, where he would fly the craft in a roller-coaster trajectory. While climbing toward the top of each “hill,” he would push forward on the controls so the trajectory of the plane exactly matched the pull of gravity. The result was a thirty-second free fall in which everything in the plane was weightless. Unrestrained astronauts in the back would float in their padded chamber. At the end of the dive, the pilot would perform a 2-G pullout that would smash everybody to the padded floor. He would then advance the throttles, climb back to 33,000 feet, and start all over. On a typical mission the process would be repeated about fifty times.

It took only one flight in the jet to understand why it was named the Vomit Comet. The plane was a barf factory. Just climbing aboard, the nose would detect a faint odor of bile. Like cigarette smoke that cannot be removed from the drapes of a two-pack-a-day addict, the smell of stomach fluid had permeated the very aluminum structure of the machine. Even when its aged bones are someday sold for scrap and melted down, the recycled aluminum will still bear the aroma of our stomach acid.