oxygen to begin flushing nitrogen out of his system in preparation for working in space-although the entire space station was set on a lower atmospheric pressure to help purge nitrogen from the system, for safety’s sake all astronauts preparing to do an EVA were required to prebreathe oxygen before suiting up.
“How you doing there, McCallum?” Boomer asked. McCallum gave him a thumbs-up and a muffled “Good, Boomer” as he continued to suit up.
Since Boomer wasn’t planning to do a space walk, his suit was of totally different design. While prebreathing oxygen, he donned a suit of thick elastic material, resembling a full-body leotard, with wires leading to a small control device. The material covered his entire body except for his head. When he nodded to the tech that he was ready, the tech flipped a switch. Fine computer-controlled elastomeric filaments in the suit contracted, compressing the material. Boomer let out a little grunt as the material pulled skintight.
Boomer’s suit, called an Electronic Elastomeric Activity Suit, or EEAS (which most wearers say resembles the sound they make when the filaments tighten up), was a simple but very effective alternative to a heavy, bulky pressurized space suit. Humans can actually survive in the vacuum of space, because the skin and vascular system is already pressure-tight-as long as the human has oxygen at the right pressure, no space suit is really needed. But in a vacuum, human tissue expands because the absence of air pressure causes gases in the tissues to painfully expand, like a balloon in an airliner. So a way was needed to keep pressure on the body to prevent the tissues from expanding.
Most space suits, like McCallum’s, used a compressor to pressurize the breathing oxygen inside the suit to keep pressure on the entire body. A skintight rubber suit would work, but it was almost impossible to don such a suit in zero-g, and any folds in the suit would cause muscle deformation. So the EEAS was developed to allow the suit to be easily donned and then re-formed so it became skintight. The electronic control system would keep pressure on the entire body even when moving but allow the limbs to move as necessary. For spaceplane pilots, the EEAS was a great alternative to bulky pressurized suits because it was easier to move around in, easier to manipulate controls, and didn’t require a tech to help strap the pilot into the cockpit.
With the EEAS on and tight, Boomer put on a special flight suit that had a locking collar for his helmet, and continued prebreathing pure oxygen. The space-suit technician then helped him into the standard flight vest, which contained pouches for survival equipment such as portable lights, carbon-dioxide scrubbers, location beacons, backup batteries, a knife, and a suit-repair kit, along with a control panel on his left wrist that showed oxygen saturation, carbon-dioxide levels, suit power, backup battery level, and EEAS control status. “How do you hear, Jeff?” he spoke into the intercom.
“Loud and clear, Boomer,” came the reply. “Good flying with you again.”
“Same here.” Boomer was amazed at how young these new guys were-McCallum looked as if he was twelve going on nine years old. “They brief you on what’s happening?”
“I was prepared to go out to Eight later on this week to fix the continuity problem. I don’t know why it’s been pushed up.”
“We might need it soonest.” He took a moment to explain the Chinese convoy headed for Somalia. “They explain the toolbox issue?”
“If I can’t do it with a soft-pack, it’s got more serious problems than I suspect,” McCallum said. A “soft-pack” was a standard EVA toolbag, with an assortment of zero-g wrenches, screwdrivers, testers, and other commonly used tools suited for working in space, plus room for replacement circuit boards, fuses, circuit breakers, software keys, and other system-specific necessities. “But I’ve got a bunch of circuit boards and components to fix fifty percent of the problems. Anything else will require a cargo run.”
“Very good,” Boomer said. “I’ll plan on staying with the Stud, but if you need me I can hop on over. Just say the word.”
“I should be okay,” McCallum said, “and I’d feel better if you stayed near the plane anyway.”
“I hear that.” They continued to go over details about the flight while they finished dressing, and then made their way to the air lock to board the spaceplane.
The S-9 Black Stallion, nicknamed the “Stud,” was the smaller of America ’s two models of single-stage-to-orbit spaceplanes. It was never designed for extravehicular activities or even docking with a space station, so there was no way (unless a passenger module and transfer tunnel were loaded in the cargo bay-this Stud was still loaded with cargo) to get from the station to the ship when it was docked except by spacewalking to the two separate tandem cockpit hatches and clambering inside.
Boomer stepped over to the air-lock inner hatch, but the docking technician stopped him. “My watch says five more minutes for prebreathing, minimum, sir.”
“My clock says I’m good to go.”
“Give it five more minutes, sir.”
“Time’s a-wastin’, Chuck,” Boomer said. “ China is stirring up the shit Earthside, and we need that garage back online.” He could see the technician hesitate. “It’s just a couple minutes shy, Chuck, and you know there’s always a safety factor built into the calculations. Let’s go.” Reluctantly, the technician nodded and floated aside.
While McCallum waited outside-safety dictated only one crewmember could use the air lock at a time, although it could fit two-Boomer entered the air lock. While it was depressurizing, the technician extended a fabric tunnel from the air lock to the spaceplane, which was docked outside on the station’s docking beam. When the air lock was ready, Boomer undogged the outer hatch, stepped into the transfer tunnel, and closed and locked the hatch behind him. “Outer air-lock door closed, ready to equalize,” he reported.
“Roger. Air lock pressurizing,” the technician reported.
“I wish we didn’t have to use the tunnel,” Boomer radioed. “I’ve made the jump to the spaceplane lots of times.”
“Not everyone is a lean mean space-faring fool like you, Boomer,” McCallum radioed back. “Besides, I don’t want to go out and retrieve you in case you missed.”
Boomer used handholds to effortlessly pull himself the twenty feet from the air lock to the Black Stallion’s cockpit. At the end of the transfer tunnel on the side of the Stud, he could see Earth spinning below him, and he resisted the urge to sightsee-he didn’t have the time to waste. “C’mon over, Jeff,” Boomer said. “I’ll have the aft cockpit ready by the time you get here.”
“On the way, Boomer,” McCallum said.
After attaching his safety line, Boomer used a lever inside a protective door on the outside of the fuselage to motor open the front cockpit canopy, reached inside, then used a switch underneath the left front cockpit sill to motor open the rear cockpit. He then went back and arranged seat straps and umbilicals. By the time he finished arranging the aft cockpit, McCallum was at the end of the transfer tunnel. “Okay, Jeff, nice and easy, just like we practiced,” Boomer said as he attached McCallum’s safety line to himself, then plugged his oxygen and communications lines into the Stud’s rear cockpit.
“There is just no graceful way to do this, Boomer,” McCallum complained.
“Just do it slowly and deliberately and you’ll minimize bumps and rebounds,” Boomer said.
The easiest way to get inside the cockpit and seated was the “jackknife” method. As McCallum floated above the cockpit, Boomer steered his boots inside the cockpit. As McCallum eased inside, he jackknifed his body to squeeze between the upper instrument panel and open canopy. This always resulted in bumps as the space suit hit off one surface, against another, then back and forth until the astronaut was able to dampen the bouncing out. Boomer steered his feet and legs inside the legs wells under the instrument panel until McCallum finally landed on his behind in the seat. “Not too bad that time-only one concussion,” McCallum said.
“I had to do all the work, and you kneed me in the head twice,” Boomer said. He stowed McCallum’s soft-pack in the small storage container behind the seat, then corralled the seat straps floating around the cockpit and buckled him in.
“Fifteen minutes, Boomer,” Kai radioed. “How’s it going?”
“Plenty of time, boss,” Boomer said. “ Mission specialist secured. I’m strapping in now.” Actually it was going to be real close to get detached in time, but Boomer reminded himself not to hurry. He checked McCallum’s umbilicals to be sure everything was stowed and secure. “Okay, Jeff, give me a systems check and a thumbs-up when you’re ready.” McCallum made sure everything was attached properly, did an oxygen, communications, and pressurization test, and gave Boomer a thumbs-up. “Okay, I’m moving into the forward cockpit now.”
Thankfully, with the EEAS space suit it was far easier to get in, almost like a terrestrial fighter jet, and in moments he was strapped in and ready. “Spacecraft commander strapped in and ready to push,” he reported.
