Gwen threw some switches and counted down to zero. "We have ignition."
As the rest of the crew watched on the auxiliary simulator external viewscreen, a computerized image of the ERV Retriever rose on a trail of simulated fire from the digitized landscape surrounding it. McGee's throat tightened. He's doing it, he's doing it.
Suddenly, the Retriever's image listed slightly to the right. A jet of computerized plume showed that Townsend had compensated, but the sudden tilt of the vehicle to the left signaled that he'd compensated by too much. Another plume in the opposite direction sent the vehicle toward the upright position, but too hard, and the image rapidly flopped over and crashed into the landscape.
The colonel heard the collective sigh escape from those gathered behind him. "Okay, people, that was just the first try. Gwen, reset for another sim."
"Roger. Here we go."
Again the vehicle flew. Again it crashed. Again it flew. Again it crashed. Townsend's attempts went on for hours, but on every try the simulated ERV lifted off the landing stage, rose a few feet, and started to lean to one side. Each time, the colonel compensated with the joystick, but always too much or too little, so that within seconds the simulated flight came to an end in a fiery crash on the virtual Martian sands.
Finally, the pilot had to admit defeat. "It's no good. Without the CPU, the ERV is completely unflyable. We wouldn't get three hundred feet. Dammit!"
Rebecca stared out the window into the slightly moonlit Martian night. "We were home free. How could this have happened?"
The question was rhetorical, but Townsend took it literally.
"I spoke to Mission Control. They reexamined the vehicle onboard health monitoring records. That board has been out since January 28, 2012."
Gwen looked up sharply. "The night the propellant was drained!"
"That's right. It must have been Holloway. He didn't just drain the ERV's propellant, he burnt out its CPU as well."
But the analytical part of McGee's mind was intrigued. "Could he have pre-programmed those other equipment failures as well? The rover breakdown, the air-exchanger problem?"
Townsend shrugged. "Maybe."
"I doubt it," Rebecca said sourly, looking at Gwen, but fell quiet when the colonel gave her a warning look.
He drew a deep breath. "There's no use denying that this is a massive setback, but don't give up hope. I'm going to confer with the flight control systems experts at JSC tonight. Maybe there's some way we can patch the flight control CPU from the Beagle into the ERV, and make it halfway flyable."
Gwen was unconvinced. "I don't think that'll work, Colonel. It's a totally different type of system."
Stripped so quickly even of this forlorn hope, Townsend could only mumble. "Well, maybe something can be done."
Rebecca turned away to stare out the window again. "Still stranded."
The colonel looked at the rest of the devastated crew. As an astronaut, he didn't have a clue what to do, but as an officer, he did. I can't let morale collapse again. I need to show some confidence. He cleared his throat. "I think it's time the four of you turned in. I'll do the telecon with JSC alone. Maybe I'll have good news for you in the morning."
The crew looked bleakly at each other. Having nothing to say, they obeyed.
Rebecca, however, could not sleep. Through the middle of the night, thoughts kept running through her head. We were so close. How could the burnt-out CPU have gone undetected for so long? True, Mission Control had been otherwise occupied, and no one had bothered much with the ERV as long as it had no fuel... but still. Whoever had sabotaged that board could also have doctored the ERV health-monitoring records. An inside job. That meant the sabotage could have been performed much more recently, most likely in the several days since the snow had been obtained. It could have been done at Mission Control... or here. Why couldn't Townsend see that?
Then she heard it. In the compartment next to hers, someone was getting up. Gwen.
Rebecca put her ear to the wall and very distinctly heard the sound of a Marsuit being zipped on. She's going EVA in the middle of the night. Another sabotage attempt! Should I tell the colonel? No. I'll follow her and catch her in the act.
Rebecca waited for Gwen to exit her compartment and then quickly and silently slipped into her own Marsuit. The flight mechanic was moving quietly herself, but Rebecca could track the sounds of her motions into the central solar flare shelter that served as the corridor to the lower deck, and then down below to the airlock. As soon as she was certain Gwen had gone downstairs, Rebecca slipped out of her stateroom and headed toward the central shelter as well.
On the way, she passed the control room and was surprised to note that Colonel Townsend was still in his chair, apparently conferring with Mason and some JSC engineers via telescreen. She managed to get past the open door without his detecting her and climbed down the stairs, closing the flare-shelter door behind her. Once she reached the lower deck and saw that Gwen had already transited out the outer airlock, she opened the inner lock door, cycled the system herself, and followed the flight mechanic out into the Martian night.
As her eyes adjusted to the darkness, Rebecca could see by the dim light of Phobos Gwen's lithe figure heading toward the ERV. She smiled grimly to herself. Gotcha, you little redneck saboteur. This time you don't get away with it.
Keeping low to avoid being spotted, the doctor followed Gwen across the dark landscape, and managed to position herself not twenty meters away as her opponent cycled the Retriever's airlock and entered the vehicle. She calculated her next move. The lock is in the ERV's lower deck. She'll go for the upper deck. That's where all the controls are. That's where she'll do... whatever it is she is planning. Rebecca counted to sixty, then followed Gwen into the return ship.
Entering the ERV's pressurized lower deck, Rebecca eased off her helmet. As she crept past one of the work-benches, she spotted a crowbar. The sight of this object, both tool and weapon, suddenly made her realize how dangerous her situation was. The saboteur had already proven murderous intent, more than once. If it's Gwen, she could attack me right here, then make up some story. Townsend would believe anything. Rebecca felt a flash of fear, but strengthened her resolve. She picked up the crowbar, took a deep breath to prepare herself for the confrontation, and boldly climbed the ladder to the control deck.
As she entered the upper deck, she saw Gwen slouching by the control panel. The major had already removed her helmet and was bent intently over the controls. Hearing a creak of metal, a whisper of footsteps, she turned to see Rebecca advancing toward her holding a crowbar.
"This time you're caught!" Rebecca's face was grim.
Gwen was startled, amazed. "You!" she shouted, and leapt at Rebecca. The mechanic moved fast; before the doctor could swing her crowbar in the close quarters, Gwen snatched the weapon out of her hand and tossed it to the far side of the room. Reacting quickly, however, Rebecca seized the instant to deliver a well-styled karate kick, catching the flight mechanic in the side.
Taken by surprise, Gwen stumbled back across the room, moving oddly in the low gravity. "Where'd you learn to kick like that—ballet school?"
Rebecca smiled proudly. "Five years of karate."
Gwen's eyes were dark with hate. "Really! Well now I'll show you what you can learn in eighteen years in the Smokies."