“What was? Transferring the BOHM?” the passenger asked.
“No—making the switch from BOHM to jet fuel in the tanker’s transfer system,” Boomer admitted. “They rinse the boom and plumbing with helium to flush all the ‘bomb’ out before the jet fuel moves through. The boron additives in the oxidizer help create a much more powerful specific impulse than regular military jet fuel, but mixing BOHM and jet fuel, even in tiny amounts, is always dangerous. Normally, the two mixed together needs a laser for ignition, but any source of heat, a spark, or even vibration of a certain frequency can set it off. The experiments we did at Sky Masters and at the Air Force test centers made for some spectacular explosions, but we learned a lot.”
“Is that how you got your nickname, ‘Boomer’?”
“Yes, sir. Perfection requires mistakes. I made a ton of them.”
“So how do you control it in the engines?”
“The laser igniters are pulsed, anywhere from a few microseconds to several nanoseconds, to control the detonations,” Boomer explained. “The stuff goes off, believe me, and it’s massive, but the specific impulse lasts just an instant, so we can control the power . . .” He paused, long enough for the passenger to turn his helmeted head toward him, then added, “. . . most of the time.”
They could virtually feel the second passenger in the back stiffen nervously, but the passenger in the front seat just chuckled. “I trust,” he said, “that I won’t feel a thing if something goes wrong, Dr. Noble?”
“Sir, an uncontrolled ‘leopards’ explosion is so big,” Boomer said, “that you won’t feel a thing . . . even in your next life.” The passenger said nothing, but just did a big nervous “GULP.”
The JP-8 transfer went much faster, and soon Colonel Faulkner was helping the front-seat passenger to get strapped into his seat in the back beside the plainly still-nervous second passenger. Soon everyone was seated and the crew was ready for the next evolution. “Our tanker is away,” Boomer said, “and as planned he’s dropped us off over southwestern Arizona. We’ll make a turn to the east and start our acceleration. Some of the sonic boom we’ll create might reach the ground and be heard below, but we try to do it over as much uninhabited area as we can to avoid irritating the neighbors. We’re monitoring the flight computers as they finish all the checklists, and we’ll be on our way.”
“How long will it take?” the first passenger asked.
“Not long at all, sir,” Boomer replied. “As we briefed on the ground, you’ll have to deal with the positive G-forces for about nine minutes, but they’re just a bit more than what you’d feel taking off aboard a fast bizjet, strapped into a dragster, or on a really cool roller coaster—except you’ll feel them for a longer period of time. Your suit and the design of your seat will help you stay conscious—in fact, you may ‘red out’ a little because the seat is designed to help keep blood in your brain instead of the G-forces pulling it out, and the more pressure you get, the more blood will stay.”
“How long will we have to stay in orbit before we can chase down the space station?” the passenger asked. “I’ve heard it sometimes takes days to link up.”
“Not today, sir,” Boomer said. “The beauty of the spaceplane is that we’re not tied to a launch pad set on one particular location on Earth. We can make our own launch window by adjusting not only our launch time but changing our insertion angle and position relative to our target spacecraft. If we needed to, we could fly across the continent in just a couple hours, refuel again, and line up on a direct rendezvous orbit. But since we planned this flight so long ago, we could minimize the flying, gas up and go, and save fuel just by planning when to take off, when and where to refuel, and being in the right spot and right heading for orbit. By the time we finish our orbital burn and coast into our orbit, we should be right beside Armstrong Space Station, so there’s no need to chase it down or use a separate Hohmann transfer orbit. Stand by, everyone, we’re starting our turn.”
The passengers could barely feel it, but the S-19 Midnight made a sharp turn to the east, and soon they could feel a steady pressure on their chests. As directed, they sat with arms and legs set against the seats, with no fingers or feet crossed. The first passenger looked over at his companion and saw his chest within his partial-pressure space suit rising and falling with alarming speed. “Try to relax, Charlie,” he said. “Control your breathing. Try to enjoy the ride.”
“How is he, sir?” Gonzo asked on intercom.