More than thirty years had passed before Dr. Adrienne Warshawski of Old Earth found a way around that danger. It was Warshawski who finally perfected a gravity detector which could give as much as five light-seconds' warning before a grav wave was encountered. That had been a priceless boon, permitting impeller drive to be used with far greater safety between grav waves, and even today all grav detectors were called "Warshawskis" in her honor, yet she hadn't stopped there. In the course of her research, she had penetrated far deeper into the entire grav wave phenomenon than anyone before her, and she had suddenly realized that there was a way to use the grav wave itself. An impeller drive modified so that it projected not an inclined stress band above and below a ship but two slightly curved plates at right angles to its hull could use those plates as giant, immaterial "sails" to trap the focused radiation hurtling along a grav wave. More than that, the interface between a Warshawski sail and a grav wave produced an eddy of preposterously high energy levels which could be siphoned off to power a starship. Once a ship had "set sail" down a grav wave, it could actually shut down its onboard power plants entirely.
And so the grav wave, once the promise of near certain death, had become the secret to faster, cheaper, and safer hyper voyages. Captains who had avoided them like the plague now actively sought them out, cruising between them on impeller drive where necessary, and the network of surveyed grav waves had grown apace.
There had still been a few problems. The most bothersome was that grav waves were layers of focused gravity, subject to areas of reverse flow and unpredictable bouts of "turbulence" along the interfaces of opposed flows or where one wave impinged upon another. Such turbulence could destroy a ship, but it was almost more frustrating that no one could take full advantage of the potential of the Warshawski sail (or, for that matter, the impeller drive) because no human could survive the accelerations which were theoretically possible.
Improved Warshawskis had tended to offset the first difficulty by extending their detection range and warning ships of turbulence. With enough warning time, a ship could usually trim its sails to ride through turbulence by adjusting their density and "grab factor," though failure to trim in time remained deadly, which was why Sirius's claim of tuner flutter had been so serious. A captain still had to see it coming, but the latest generation detectors could detect a grav wave at as much as eight light-minutes and spot turbulence within a wave at up to half that range. The problem of acceleration tolerance, on the other hand, had remained insoluble for over a standard century, until Dr. Shigematsu Radhakrishnan, probably the greatest hyper physicist after Warshawski herself, devised the inertial compensator.
Radhakrishnan had also been the first to hypothesize the existence of wormhole junctions, but the compensator had been his greatest gift to mankind's diaspora. The compensator turned the grav wave (natural or artificial) associated with a vessel into a sump into which it could dump its inertia. Within the safety limits of its compensator, any accelerating or decelerating starship was in a condition of internal free-fall unless it generated its own gravity, but the compensator's efficiency depended on two factors: the area enclosed in its field and the strength of the grav wave serving as its sump. Thus a smaller ship, with a smaller compensator field area, could sustain a higher acceleration from a given wave strength, and the naturally-occurring and vastly more powerful grav waves of hyper space allowed for far higher accelerations under Warshawski sail than could possibly be achieved under impeller drive in normal space.
Even with the acceleration rates the compensator permitted, no manned vessel could maintain a normal space velocity above eighty percent of light-speed, for the particle and radiation shielding to survive such velocities simply did not exist. The highest safe speed in hyper was still lower, little more than .6 c due to the higher particle charges and densities encountered there, but the closer congruity of points in normal space meant a ship's apparent velocity could be many times light-speed. Equipped with Warshawski sails, gravity detectors, and the inertial compensator, a modern warship could attain hyper accelerations of up to 5,500 g and sustain apparent velocities of as much as 3,000 c. Merchantmen, on the other hand, unable to sacrifice as much onboard mass to the most powerful possible sails and compensators the designer could squeeze in, remained barred from the highest hyper bands and most powerful grav waves and were lucky to make more than 1,200 c, though some passenger liners might go as high as 1,500.
And that brought Honor right back to Sirius, for the ship in front of her obviously had a military-grade drive and compensator. Her sheer mass meant her compensator field was larger and thus less efficient than Fearless's, but no freighter should have been able to pull her acceleration. Even a superdreadnought, the only warship class which approached her mass, could only manage about four hundred and twenty gees, and Sirius was burning along at four hundred and ten. That left Fearless an advantage of barely a hundred and ten gees, little more than a kilometer per second squared—and Sirius had a head start of just under fifteen minutes.
It would have been worse if Fearless hadn't been at standby or Dominica Santos hadn't cut corners and chopped almost a full minute off the time it took to put her drive fully on line. As it was, Honor could still overhaul before Sirius reached the hyper limit, but not with as much margin as she might have wished. Sirius would hit the hyper limit in just under a hundred and seventy-three minutes from the time she left orbit. Honor had been in pursuit now for almost ten minutes. By cutting the safety margin on her own compensator to zero, she could match velocities with the freighter in another forty-six minutes, but it would take her over an hour just to reach effective missile range. Completely overtaking the freighter would require just over another hundred and seven minutes, leaving her less than twenty minutes before Sirius reached the hyper limit. And even if she did overtake completely, forcing the freighter to heave-to would be far from easy. Worse, momentum alone would carry Sirius beyond the hyper limit, even if she braked at max in response to Honor's demand, unless she began her deceleration within the next hour and a half, and Honor had no way of knowing just how far beyond the hyper limit a Havenite battle squadron might be lurking. No normal space sensor could see across the hyper wall. The entire Havenite Navy might lie less than a light-second beyond the limit, and no one in Basilisk would know a thing about it, so it was entirely possible Sirius needed only to break into hyper at all to accomplish her mission.
Which meant that, somehow, Honor had to stop her within the next ninety-seven minutes. If she didn't, then the only way to prevent her from translating into hyper would be to destroy her.
Captain Johan Coglin sat on his bridge. He'd run out of curses ten minutes before; now he simply sat and glared at his display while anger flowed through his mind like slow lava.
Operation Odysseus had seemed like a reasonable plan when he was first briefed for it. A few too many ruffles and flourishes, perhaps, but reasonable. There'd been no special reason why they had to use his ship for it, yet no one had listened when he suggested they use a genuine freighter. They'd wanted Sirius's higher acceleration levels and hyper speed "just in case," and he'd been far too junior to argue the point. And, he supposed, if things had gone as planned, it wouldn't really have mattered in the long run. Only the idiots who'd orchestrated the operation should have realized it would never work from the moment Fearless replaced Warlock on Basilisk Station. They should have scrubbed it weeks ago, and he'd told Canning that.