by Weber, David
Yanusa-Mahrdissa blinked, impressed despite himself. Of course, the army officer was right about the Devil Buff’s sheer power. It wasn’t at the very top of Ram’s Horn Heavy Equipment’s line of bulldozers. That distinction belonged to the Black Rhino, the largest and most powerful bulldozer ever built (yet), but the Devil Buff was no slouch. Like everything else in RHHE’s catalog, it was built “Ram Tough” and its uniflow six-cylinder engine—two banks of three cylinders each mounted back-to-back—produced pressures of up to five hundred pounds per square inch and gave the bulldozer almost sixteen horsepower per ton. The obstacle it couldn’t move was rare, but its maximum speed was no more than ten miles per hour under ideal circumstances, and even then the operator was taking far too many hours off its tracks’ design life.
“When the Army approached RHHE about the Bison, their track designers thought the quartermaster general was out of his mind,” chan Mahsdyr put in with something suspiciously like a grin. “The Artillery was already experimenting with steam tractors as prime movers, especially for the heavy guns, but Division-Captain chan Stahlyr’s ideas were a lot more…ambitious than that. In fact, I think at least half the Army thinks he’s out of his mind.” The dragoon company-captain shook his head. “He has this idea the entire Army—infantry, dragoons, artillery, and all—should be what he calls ‘mechanized.’ He wants to move everything cross-country as fast or faster than cavalry could cover the same terrain.”
Yanusa-Mahrdissa started to chuckle. Then he realized the company-captain was completely serious and glanced at chan Yahndar, who shrugged.
“It’s not as crazy as it sounds, really, Master Yanusa-Mahrdissa. The emperor’s been quietly pushing the Army’s modernization for more than fifteen years now. The Empire hadn’t fought a major war in over a century before he took the throne. We’ve been involved in the occasional peacekeeping action, but not against a first-rate opponent, and His Majesty felt we’d allowed our doctrine and thinking to stagnate, especially given the advances in steam engineering TTE’s expansion has been driving. Division-Captain chan Stahlyr’s only about fifty-two years old, but the heads of the Artillery, Cavalry, Infantry, and Engineer Boards are almost as young as he is and they’re all what His Majesty calls ‘forward thinkers.’ He told them to think about Army doctrine and equipment as aggressively as the Navy thinks about designing the next class of battleships, and Division-Captain chan Stahlyr obviously took him seriously.”
“That’s certainly true,” chan Hurmahl agreed. “He had a pretty damned clear idea what he wanted, and he wasn’t about to take no for an answer. At first, Ram’s Horn told him that if he wanted those sorts of speeds, he should just buy commercial steam drays, but they didn’t have the capacity or the cross-country capability he wanted. So they came up with a design based on a modification of their standard eight-ton dray which is pretty impressive. They call it a ‘half-track,’ since it has a tracked suspension in the rear and steering wheels in front, and it can handle terrain that would kill any wheeled vehicle. They were damned proud of it, because it really is a huge improvement over existing drays, and the QMG was happy to get it. In fact, the Army standardized it as the Halftrack of 5051—the troops named it the ‘Steel Mule’—and ordered over two thousand of them, but it still couldn’t meet his specifications, especially for payload and towing power, since its maximum capacity’s only about a ton and a half, so he sent them back to the drawing board for something better.
“When he insisted he was serious—and they realized he wasn’t going to go away just because it was impossible—they actually looked at the problem. And since they’d been right that no existing suspension could give him that kind of performance, they had to come up with a new one. Once they recognized that, they got into the spirit of the thing, accepted the challenge, and came up with a pretty damned radical solution. Instead of conventional leaf springs like the Buffalo’s, the Bison uses vertical springs. The height of the spring well was still too limiting, so they added a bell crank to swing vertical motion to the rear, in addition, which reduced the vertical stroke by about twenty-five percent. The combination means the Bison’s road wheels can displace over twenty inches vertically, and the new springs are actually tougher than the old-style leaf designs. I’ll let you imagine what kind of obstacle that means it can handle.”
Yanusa-Mahrdissa pursed his lips in a silent whistle, and chan Yahndar snorted.
“Don’t let him pull your leg too hard,” he suggested, and the Shurkhali looked back across the desk at him. “Oh, the Bison’s suspension can do everything he’s claiming for it, but the tracks are still more fragile than we’d like. RHHE’s retrofitting the newest design, with rubber-backed track blocks, to everything coming down the line behind us, and we’re supposed to be getting an ample supply of spares by the time the main body’s ready to follow us. Unfortunately, we don’t know for certain they’ll get here, just like we don’t know how well the new design’ll hold up. And even if all the new hardware works perfectly, trying to take one of them cross-country at anything like its top speed will jar your teeth right out of your head. The nosebleeds can be pretty bad, too, and if there’s any unsecured gear flying around the black eyes get positively spectacular. And it took some bright lad at Ram’s Horn over a year to come up with the notion in the first place. Then they spent most of another year working out the bugs in the original concept. And they only reached the deployable stage a little over two years ago, so no one has enough experience with them to know whether or not Division-Captain chan Geraith’s idea is really going to be workable.”
“I imagine not,” Yanusa-Mahrdissa said after a moment. “It does make me feel a bit better about the whole notion, though.”
“Like I say, they’re shipping additional units and replacement tracks forward as quickly as Ram’s Horn can get them off the assembly lines,” chan Yahndar said. “And the Mark Two uses kerosene instead of pelletized coal. It’s got a more powerful engine and a longer range, too.”
“How much range are we talking about?” Yanusa-Mahrdissa asked.
“Under decent conditions in open terrain, the Mark One’s good for over two hundred miles on a single bunker of coal, and it carries enough boiler feed water for at least four hundred. I understand the Mark Two will be good for two or three times the Mark One’s range, given the advantages of kerosene. The Mule can make three hundred miles on roads and about two thirds of that cross-country, as long as it’s not too heavily loaded and the going’s not too soft.”
The Shurkhali was impressed afresh. The Devil Buff devoted so little of its volume to fuel, since refueling was seldom an issue, that he would have been astonished if one of the bulldozers could have traveled as much as one hundred miles before refueling. He was less surprised by the feed water endurance, however. The Devil Buff’s coiled monotube boiler used very little water—less than two gallons for the entire system—under very high pressures, and the uniflow engine was downright miserly in steam loss compared to older style expansion engines. And chan Yahndar was right about kerosene’s advantages over coal. Not only did it have a higher caloric efficiency, but a given volume of kerosene contained none of the air spaces between individual lumps or pellets of coal. The powdered coal used in most maritime and industrial power plants had many of the same advantages, but installing the crushing machinery to powder coal on-site in a land vehicle was hardly practical, and Yanusa-Mahrdissa would rather try to transport old-fashioned black powder than pulverized coal. It would certainly be a less explosive challenge! That was the reason the pelletized fire boxes had been developed for vehicular use. The coal was powdered, then mixed with water and a bonding agent and forced through dies which produced uniform pellets about half an inch in diameter. It wasn’t as efficient as injecting the powder directly into the flues, but the pellets packed “tighter,” with smaller air spaces, than lump coal, and they were both easier to shovel and could be fed into the fire boxes mechanically in most cases.
Despite which, ke
rosene was a far better fuel choice in the end. That was why TTE was converting a lot of its heavy equipment to liquid fuel.
“That’s going to make things at least a little easier,” he said out loud, “and I realize we’re talking about a single division, not an entire corps. How many Bisons are we actually going to need?”
“The Model A’s the personnel-carrying version,” chan Yahndar replied, “and each of them can transport two cavalry squads—minus their horses, of course. Assuming we had enough of them for the entire division, we’d need almost five hundred.” He smiled faintly at the civilian’s horrified expression. “Fortunately for your logistics concerns, we don’t have anywhere near that many, though. For that matter, the Army’s been buying about three times as many Model B’s—the pure tractor variant—as Model A’s. We’ll be lucky if Division-Captain chan Geraith is able to scrape up two hundred of the A’s. We’ll probably have several hundred Mules to support them, though, and the Mules run on kerosene, like the Mark Twos.”
“That’s still going to burn Saramash’s own pile of coal,” Yanusa-Mahrdissa pointed out. “Then again, we’ve already got Saramash’s coal pile right here at Shosara.” He smiled another crooked smile. “Our own heavy equipment’s got quite an appetite for it, you know. Moving it’s still going to be a pain, though.”
“That’s why the Army’s also scraping up every dray it can find up-chain from here and shipping them forward. I understand TTE’s combing out its own steamer fleet, too, even if no one had come up with any hard numbers for the division-captain before he sent us on our merry way. I think we can confidently assume there’ll be quite a lot of them, and we’ll probably end up using some of them to move troops, as well, especially after the first infantry comes forward to join us. And at least we won’t have to move as much fodder! That’s one thing a dragoon’s used to calculating. It doesn’t feel right leaving the horses behind, but the Bisons will actually move a lot more cargo per ton of ‘fuel’ than animal traction can. And each ton of it will be a lot less bulky than fodder, too.”
Yanusa-Mahrdissa nodded silently, his brain grappling with the quantities of coal, kerosene, and other supplies which would have to be transported through what amounted to a howling wilderness.
Resym was going to be bad enough. The railhead had already extended the next best thing to a thousand miles beyond the entry portal, located near the site of the small town of Shdandifar in the New Farnalian republic of Darylis, but it was almost three thousand miles—over a thousand of them through the heart of the Dalazan Basin’s rain forest—to the exit portal, near where the Limathian river city of Paditharyn ought to be. They were fortunate the existing rail line covered over half of the rain forest crossing, and even more fortunate that TTE survey parties had already laid out the railbed for the entire trip. The fact that the Portal Authority had surveyed dozens of identical planets meant picking a route was seldom that great a challenge, although there were exceptions, of course. But someone still had to go and hike or ride the entire route to be sure there weren’t any surprises; local and ground erosion, watersheds, landslides, tree growth patterns, and even earthquakes could provide plenty of those.
In this case, though, they knew now where to expect the greatest difficulties, and the Portal Authority’s standard practice of using the rail line’s planned route for the initial animal-drawn traffic of exploration meant there was at least a rough roadbed hacked through the jungle. It was little more than a muddy trail in far too many spots and the speed with which the jungle encroached on and reclaimed roadbeds had to be seen to be believed. Nor had that trail ever been intended for vehicles as heavy as the 3rd Dragoons Bisons and Steel Mules or for the sheer quantity of traffic which would shortly go streaming down it. But his own advanced construction parties were improving it steadily. It would offer a starting point, at least, and if the Bisons’ towing capacity was really that great…
“How many Bisons do you have available right now, Battalion-Captain?” he asked.
“We’ve got about a dozen aboard the other ships,” chan Yahndar replied a bit cautiously. “We didn’t see any point in bringing along more than that, especially with how tight shipping is and how much heavy construction equipment Master Banchu needs to move this way. Besides, the entire idea is for our initial scouting efforts to be carried out on horseback. The kind of smoke trail a column of Model A’s throws up would be a bit hard to conceal.”
“I understand that,” Yanusa-Mahrdissa said. “But one of the key things we need to worry about is getting enough heavy equipment far enough forward for our bridge builders. For that matter, moving the bridging materials is going to be a problem, and there are areas—especially in Resym—where we’re simply going to have to do major road improvement—a lot of major road improvement—if it’s going to support the amount of traffic Division-Captain chan Geraith’s talking about putting down it. The tractor-trailer steamers we’d normally use to transport our bulldozers, graders, and steam shovels are bigger than hell and not very well suited for breaking trail through the middle of a rain forest. But if we can tow the flatbeds behind your Bisons instead of the regular wheeled tractors we can probably move the heavy stuff a lot farther forward a lot faster. And if you’re going to be moving on horseback initially, anyway…”
“I see your point.” Chan Yahndar nodded. “We may be able to trade off to some extent. I know you’ve got a lot of standard steam drays working around the railhead. Maybe we could give up a few Bisons for heavy towing and replace them with wheeled drays which are individually lightly loaded enough to get through and give us the capacity we’ll need. For that matter, we could trade them out for Mules as they come forward. In fact,” he frowned in sudden thought, “I think we need to suggest just that to Division-Captain chan Geraith. We didn’t have any of the Mules here in Traisum when we started out, but if he can get enough of them forward to support us while we scout the route, it would help a lot from a tactical perspective, as well.”
“How?” Yanusa-Mahrdissa asked curiously. “I thought they didn’t have much payload capacity,” he added, and chan Yahndar snorted.
“They don’t, compared to a Bison, but they’re faster than a Bison, so they wouldn’t have much trouble catching up to us well before we hit Thermyn, and we won’t have anywhere near the logistical requirements the main column will. More to the point, though, they burn kerosene, not coal, and they burn hot enough there’s no visible smoke. We’d be a lot harder for some dragon or eagle-lion to spot, and we’d be able to leave all of our Bisons with you for the heavy hauling.”
“I think that’s certainly an idea worth looking into,” the Shurkhali agreed. “And I know Master Banchu plans to transfer all his heavy equipment and heavy lift transportation to this side of the Vandor as quickly as he can find shipping for it. Eventually, we’ll have plenty of steamers available to move stuff forward from Shosara; the problem’s going to be how quickly we can improve the roadbed enough for them to do the moving.”
“The division-captain’s given me pretty much carte blanche on how I use the transport assigned to me,” chan Yahndar said. “Why don’t you and Battalion-Captain chan Hurmahl put your heads together and come up with the best estimate you can for how we divvy up our resources while we wait to find out about the Mules’ availability?”
“We can do that. Of course, anything we come up with at this point’s going to be pretty much a WAG.”
“Understood. On the other hand, you’re going to have at least a month before the division-captain gets the main column as far forward as Kelsayr, and any of the infantry’s going to be more than a month behind that.”
“Granted, but sixty days isn’t anywhere near as long as it sounds, especially when we’ll need to be setting up forward fuel and supply dumps. Which brings me to another point. What kind of depths can one of these Bisons ford?”
“They’re designed to ford up to five feet of water,” chan Mahsdyr replied for his CO. “The Mules can ford up to about t
he same depth, and I’ve seen Bisons manage just over six. Of course that was crossing a streambed where we knew exactly what the bottom conditions were. I think the Mark Twos, at least, can be fitted with a deep fording kit that would get them across up to ten feet if they seal all the hatches and openings. At that point all that would be above water would be the exhaust and the snorkel, so steering would get problematical as all hells and the risk of stranding one of them permanently in the middle of a river goes way up. Crew risk goes up, too. And the Mules can’t go anywhere near that deep. On the other hand, they can use a standard scissors bridge or pontoon bridge, and the Bisons are too heavy for that. But you can probably count pretty solidly on five or six feet for either of them, especially if your fabricating crews are up to bashing a deep fording kit of our own.”
“Really?” Yanusa-Mahrdissa brightened. “That’s better than I expected. In fact, it’s probably good enough to get us across eighty or ninety percent of the water obstacles in Resym. That would ease the strain on our bridging crews a lot!”
“I know we have to worry about getting across Resym,” chan Yahndar said, “but all we really have to worry about there is the terrain. Once we hit Nairsom, we’re going to be crossing ‘only’ five or six hundred miles of Roantha and northern Thanos in the middle of winter. It’ll be a lot flatter, and we won’t have triple-canopy jungle to worry about, but the temperature’s going to be a bitch. And then, assuming a blizzard doesn’t come along and kill all the damned horses, we’ll hit the Chindar Portal in Thermyn.”
