Stephen Coonts - Combat

Soon I will show them that we mean our threats.

Seven and a half hours into her journey to reach the station, Diane Williams began to feel the effects of the carbon dioxide her nearly discharged Primary Life Support System backpack could not fully extract from her EMU suit. The centrifugal fan of the PLSS, running at nearly twenty thousand RPM, slowly failed to draw the contaminated oxygen from the normal rate of 0.17 cubic meter per minute down to 0.14 and dropping — according to her chest-mounted display. In addition, the slow warming trend inside the suit also told her that the PLSS feedwater pump and heat exchanger and sublimator, designed to maintain a steady flow of chilled water through the hundreds of feet of plastic tubing lacing the LCVG underwear Diane wore, were also fading.

The situation would only get worse, with the suit slowly turning into a greenhouse as humidity and temperature got out of control, fogging the faceplate and eventually suffocating her.

She had to act, and fast, while she could still see through the pressurized polycarbonate plastic sphere underneath the gold-coated visor protecting her eyes from the blinding ultraviolet rays of a sun that had loomed over the horizon a half hour ago. Diane activated the EMU’s purge valve to bleed the carbon dioxide into space before switching to the secondary oxygen pack NASA added to the bottom of the unit to ensure the safety of astronauts in case of main PLSS failure.

Operating in open-loop mode, where the oxygen she breathed did not get circulated back to the PLSS but went through the purge valve, Diane checked the timer on the chest-mounted display. She had around fifty minutes’ worth of oxygen left.

That should be enough.

Squeezing the last of the nitrogen pressure inside the Manned Maneuvering Unit’s tanks, Diane used the station’s long frame, only five hundred feet away, to block the blinding sun. So far, the station showed no sign of alarm.

Soon that’ll change , she decided, aware of the station’s proximity sensors. Although they had not been sensitive enough to detect her yet, they were designed to detect any object with a radar cross section larger than a half foot getting within five hundred feet of the station.

Her viewplate beginning to fog and her EMU suit temperature climbing out of the comfort zone, Diane opened the purge valve a bit more, which also meant her oxygen supply would decrease at a faster rate. She didn’t have a choice. She had to keep the helmet from fogging at all costs while commanding the MMU to thrust her toward the hyperbaric airlock attached to the Unity Module.

UNSC15KTSN001 HAS BEEN SELECTED INSERT VALID UNSCF BADGE TO ACTIVATE

******00:59******

Sergei Dudayev was ready when the slot under the keyboard opened. Upon inserting the badge, the screen changed to a blinking:

UNCS15KTSN001 IS READY TO LAUNCH

The Russian cosmonaut smiled. Then the station’s proximity alarm went off.

Diane Williams noticed a number of red lights flashing on some modules. The proximity alarm motion sensors had detected her. She needed a decoy.

Unstrapping the HandHeld Maneuvering Unit from the side of the PLSS, Diane disengaged herself from the backpack propulsion system that had carried her all the way there. A hard kick against the MMU to push herself toward the station, and Diane watched the MMU tumble out of control away from her.

Now came the tricky part. All she had to propel herself toward the station was the HHMU, very similar to the ones used for EVAs during the Gemini Program of the 1960s, and seldom used by modern-day space voyagers because of the readily available and highly sophisticated MMUs.

Diane held the three-jet maneuvering gun with both hands. There were two jets located at the ends of the rod and aimed back. A third jet, located at the center of the rod, faced forward. Remembering the technique used by those early space explorers, Diane Williams centered the gun close to her lower chest — the place she estimated to be closest to her center of mass. Visually lining up the rear-facing jets with the airlock hatch roughly three hundred feet away, Diane fired the gun, releasing a symmetrical burst of compressed oxygen from both jets, propelling herself more or less in the desired direction.

Finally learning the limitations of the HHMU — and also the frustration of those Gemini astronauts — Diane found herself making slight correction on the firing angle of the jets while lowering the gun to her waist, below the chest-mounted display to avoid a slight rotational motion induced by firing the thrusters out of line with her true center of mass. Slowly, using a combination of forward thrusts and also firing the reverse thruster to break her momentum, Diane reached the airlock hatch.

The proximity alarms blaring, Sergei Dudayev checked the radar and verified the existence of an object at less than five hundred feet from the station.

Puzzled, he floated back into Unity and up to the cupola. Using a restraint system that enabled him to rotate easily for viewing through any of the windows, the Russian spotted an empty Manned Maneuvering Unit drifting away from the station.

An MMU?

Realizing that the ISS didn’t carry any MMUs, Sergei concluded that unless for some very strange law of physics one of Endeavour’ s MMUs had been dislodged from its flight station and floated in this direction, the presence of the backpack system could only mean one thing.

After performing an emergency bleed of the air inside the airlock by using the small control panel built in on the D-shaped EVA hatch door, Diane Williams pressed her left hand against the manual unlocking lever while holding on to the adjacent handle with her right. Three full clockwise turns, and she pulled the hatch door back several inches before a spring-loaded mechanism rotated it upward. Floating inside the airlock, Diane closed the hatch behind her and repressurized the compartment.

Sergei noticed the red lights blinking on the control panel of the crew support station, which told him that an emergency airlock bleed had been done. The EVA hatch had been opened, then closed, and now the airlock was being repressurized.

Cursing his stupidity for assuming that the crew of Endeavour had perished in the attack, Sergei kicked his legs against the side of the cupola and reached Unity, sighing in relief when noticing that the hatch connecting the airlock to the bottom of the node was still closed. Without further thought, he locked it from the inside.

Diane finished pressurizing the airlock and noticed the green light above the hatch connecting her compartment to Unity turning red. Realizing that the Russian had most likely found her, she decided not to depressurize her EMU suit just yet. Instead, she reached for the communications panel on the side of the airlock wall and set it to the standard EVA mode UHF frequency 121 Mhz. Next, she remotely switched on the station’s K-band antenna to close the ISS-Houston link via a TRDS and White Sands Tracking Station.

“Houston, this is Endeavour ’s Mission Commander Diane Williams, over.”

“Wh — what? Come in … come in, Commander! Jesus Christ! We thought … great to hear from you!” Diane heard an unfamiliar voice coming through.

“I have little time before Dudayev catches on and cuts us off. I’ve reached the station. I’m trapped inside the airlock and have less than twenty minutes left of oxygen in my PLSS.”