“Okay Mercy I, we believe that the P & P alert is the key. The pressurants and pressurization algorithm is telling us that we’ve got either an ACS roll thruster stuck open or there is a leak in the propellant line that is rapidly venting. But since the thrust appears to be very stable and directional, our best guess is the thruster.”
“Uh, okay, Houston. What is our work-around?” Bill inched his hand closer to the manual-control switch.
“Bill, you need to see if you can reboot the ACS. The PROP team thinks that there might be a valve stuck open, and the reboot will close it.”
“Okay. Roger that. Start with the reboot sequence.”
“Roger that, Mercy I. Here we go. ACS SEQ 999GGH3…”
It took Stetson more than seven or eight very long minutes to type in the commands. During that time Tony Chow began retching and heaving into a barf bag as best he could manage. The Chinese crew members seemed to be handling the situation a little better.
“Alright, Houston, hitting reboot now.” Bill tapped in the final command code. When he did, everything went black. “Jesus!”
“What the…?” Tony forgot his barf bag when the lights flickered out.
“Houston, we’ve had a complete power failure here. All my boards are out.” Bill started tapping at reset switches and breakers, but nothing seemed to happen. For some reason, the communications system was still up.
“Mercy I, we’ve lost all feeds but the Ku-band links. No telemetry whatsoever is making it to us. We are looking into it.”
“Roger that, but we are still spinning up here.” Bill was beginning to think that the ship was about to come apart at the seams. They had comm-system power. That meant something. They needed the ACS back online if he was going to stop the spin.
“Bill, my screen is coming on!” Tony shouted.
“What does it say?” Bill tried his best to move his head in that direction, but the spin kept him from doing so.
“It’s a hard reset! I think the entire system shut down and is now starting to boot back up.” Tony reached up and tapped the enter key on the console, and his screen lit completely up and started loading the operating system. Then the lights flickered back on, and Bill could hear the carbon dioxide scrubber fans start up again.
“Houston, be advised that we’ve got systems coming back online.” Bill’s screen blinked back on and began loading the mix of drivers loaded onto it to command the spacecraft. “Any idea what just happened?”
“Uh, we’re working on that, Mercy I. Right now we believe we had a main power-bus failure and back-up power has kicked in,” Houston replied.
“Roger that. Now we need to stop this rolling.” Bill waited as the system came completely back up. “Houston, I have an initial idea that will help.”
“Go ahead, Bill.”
“I want to redeploy the solar arrays.” Bill understood that they were spinning about the roll axis just like a figure skater on ice doing an axel. When figure skaters let out their arms, it slowed their rate of spin due to the law of conservation of angular momentum. Extending the solar arrays should have the same effect. It probably wouldn’t stop the spin, but it would slow it to something a little more tolerable.
“We agree with that, Bill. Go ahead and cycle the solar arrays, over.”
“Roger that, Houston. I’m making my way through the procedure now.” Bill tapped several commands, and then the graphic of the exterior view of the ship showed the solar panels extending. Bill could feel some vibrations from the gimbal motors. The lights turned green for both arrays, showing that they had been fully extended. He held up his arms. They didn’t feel as weird as they had before.
“Did it work, Bill?” Tony asked.
“Don’t know. I feel different, but we’ll have to wait until the gyro is fully back online. Another minute will tell.” So they waited.
And waited.
When the Orion completely rebooted itself and all systems were back online, the directional gyro showed that the ship was still spinning, but at about half the speed it had been before. That was a little more tolerable.
“Okay, Houston, we show that our roll rate has dropped to a constant speed. Also note that the roll thruster appears to have turned itself off during the reboot.” Bill hit the auto ACS icon and activated the automated-control system.
Bang! Bang! Bang, bang, bang!
Several attitude-correction thrusts were initiated by the computer, and then the roll rate showed zero on the directional gyroscope. The ship had stopped spinning. And not a moment too soon, as Tony Chow was reaching for his barf bag once again.
“Houston! That worked. We’ve stopped spinning, and now I believe we are back in business. I’m setting up a full diagnostic run now to see what shape we are in. That should only take a few minutes.” Bill tapped in several key sequences and then leaned back to look out the docking windows. Earth filled the view, and it was awesome. From the look of things, Bill was guessing that they were somewhere over China at the present moment.
“Hey, everyone. Take a look out the window.” Chow, Hui, and Stetson each took a turn unbuckling and floating up to the windows and peering out at Earth—at home.
Bill watched as his home planet rotated beneath them. From the looks of the size of things, it seemed about right. He’d been in low Earth orbit many many times now and knew what it looked like. One thing didn’t seem to add up, though. If he had his bearings straight, then it appeared to him that they were flying much closer to an equatorial orbit than the orbit of the International Space Station.
“Uh, Houston, is there something else you need to tell us?”
Chapter 33
“Mercy I, something went wrong on aerocapture.” Mission control started in with the bad news. “You might have figured out by now that you aren’t at a fifty-two degree inclination in your orbit.”
“I was beginning to wonder about that, Houston.” Bill replied. “So, where are we?”
BANG! Bang, bang, bang! A big jolt resounded through the ship, followed by three ACS bursts. Then there were more ACS burns. Bang, bang, bang. Bang, bang.
“Holy crap!” Bill grabbed at his armrest with one hand to steady himself. With the other he tapped at the attitude-control diagnostics and the directional-gyro screen. “Houston, we’ve got something going on here. We’re rocking and rolling like crazy, and the ACS is trying to keep up with it.”
Bang. Bang, bang, bang, bang. Bang, bang. All the ACS thrusters seemed to be firing to correct for something, and the ship continued to rock with each bang.
“Mercy I, we show P & P PROP warning again, and the fuel level in ACS is dropping rapidly.”
“Roger that, Houston. The ACS is firing almost continuously now.” Bill considered taking control, but he had no idea what the ship was doing and why the computer felt it needed the ACS control thrusters to fire. Something was pushing them. “Tony, can you see anything out your window? I’ve got nothing on this side.”
“Bill! There’s something spewing sparkly stuff in a jet out the side over here.” Tony sounded upset.
“Alright. Take it easy, Tony.” Bill didn’t like the sound of that. It was never a good idea to be spewing anything out of the ship if you didn’t have to. “Houston, we’ve got something leaking out of the capsule near the starboard side up at the nose.” He didn’t have to remind anybody that that was the location where Tony had taken up target practice before the aerocapture. That big noise they heard during the capture process might have been something coming loose up there.