We Drive a Locomotive

From the September 1990 issue of Car and Driver.

We’ve been giddy from speed in Cor­vette ZR-1s and dizzy from the price of Cadillac Allantés, but we’ve never driven a General Motors product that affected us like this before. GM’s new SD-60 is a brutal-looking three-seater equipped with everything an enthusiast could hope for: all-wheel drive, all-wheel steering, a massive midship-mounted V-16 engine, and brakes powerful enough to stop a freight train. Developed exclusively for tracks, it corners on rails. It belts out enough power to light up a small town. And it’s packed with computer-con­trolled everything—in fact, it’s so complicated it takes an engineer to run it.

Unfortunately, the SD-60 is one vehi­cle you won’t see much of unless you spend a lot of time hanging around tracks. That means the only way to sam­ple one is to undertake basic training­—which is just what we did. We were only too pleased when General Motors’ Electro-Motive Division saw fit to swing open the gates to its factory and test tracks in LaGrange, Illinois, for us. We came, we saw, we tested—and in the end fulfilled a childhood dream surely shared with many a responsible grown-up: We drove a train.

The GM guy on the scene was Keith Mahalik, a young engineer—mechanical, not railroad—whose job it is to keep in touch with EMD’s customers and devel­op ever-better software for the computer systems on today’s locomotives. Mahalik also has automotive proclivities: He de­scribe himself as “a horsepower guy” who likes big engines of all kinds, some­thing his personal transportation fleet confirms. Parked in his garage are a 1967 Corvette convertible motivated by a 427-cubic-inch V-8, a 1971 Olds 4-4-2 con­vertible equipped with the high-output W30 package, and a 1967 Olds 4-4-2 street rod pumped full of vitamins by a Detroit Diesel 6-71 supercharger.

Mahalik showed us into his office be­fore our morning plant tour. Fittingly, the big brick building is past its prime and a little shabby—like an old train sta­tion. The 343-acre LaGrange plant com­plex was opened in 1935, several years after GM bought Electro-Motive Engi­neering Corporation. The offices of the service technical engineers are a labyrinth of gray desks and steel partitions on the third floor. You walk up.

The 1940s were the glory days for La­Grange. That’s when diesel-electric loco­motives eclipsed their steam-powered forebears. Though it’s hard to imagine now, steam locomotives had ruled the railways up through the 1930s. They were immensely powerful—some pro­duced as much as 6000 horsepower—and they had the potential for speed. Today, Japan’s much-heralded bullet train averages 125 mph, and the French TGV, which hits 160 mph on its regular routes, is consid­ered a marvel. Sixty years ago, however, the fastest U.S. steam locomotives got passengers to their destinations at better than 100 mph.

Then, in 1939, GM’s Electro-Motive Division introduced the first successful diesel-electric locomotive, the FT103. It took four of EMD’s new engines hooked in tandem to match the power of one big steam locomotive, but the FT103’s lower operating costs and cleaner-running powerplant—no soot, no cinders, no clouds of smoke—won the railroad over. Versions of the slab-sided FT103 were produced through 1955 and used for many years afterward.

Inside a Locomotive Factory

As we headed for the factory floor, Mahalik explained how diesel-electric lo­comotives work. “The basic layout is the same today as it was when the FT103 was introduced. The diesel engine powers a generator, and the electricity from the generator drives six direct-current elec­tric motors located at the axles.” Doing it this way eliminates the need for a transmission. “Each electric motor acts like an infinitely variable transmission,” Mahalik pointed out. As the output from the main generator is increased, the electric mo­tor puts out a smooth flow of power; the more juice that goes in, the more motive force that comes out. “Another advantage,” Mahalik added, “is that electric motors have tremendous low-speed torque.”

More than just the layout of locomo­tives has remained the same for the past half-century. After just a few minutes on the factory floor, it became apparent that the way locomotives are made hasn’t changed much since the 1940s, either. The scene was pure Smokestack Ameri­ca; it could have been almost any time in the last 50 years. The woodblock floor was covered in a grimy black goop, and an oily haze hung in the air.

We were in the engine shop. A lone worker labored at a forging press, stamp­ing out exhaust valves. They glowed red hot as they fell into their steel holding container. Farther down the line, a long valve stem was being fuse-welded to the stubby tulip in a spray of sparks. The fin­ished valve would be almost the size of a clarinet.

It’s ironmongery on a grand scale. “The SD-60 locomotive you’ll drive to­day uses our latest engine, the 16-710G3,” said Mahalik. “It’s a V-16, with turbocharging and aftercooling. We rate them by cylinder displacement.” So the 16-710G3 engine in the SD-60 displaces nearly 710 cubic inches per cylinder. That’s, uh, a total of 11,353 cubic inches, about 186 liters. Mahalik smiled. Jeez.

Then we saw one of the engine blocks sitting on the floor, waiting for assembly. Welded up from huge slabs of rolled steel and massive forgings, it was the size of a motorboat. A box of connecting rods was sitting nearby. They were as big as tennis racquets and a lot heavier. Picking one up required two hands. “It’s 25 pounds,” said Mahalik.

To build an engine that’s going to move mountains—a single SD-60 loco­motive can haul as much as 12,000 tons of train—you’d expect all of the compo­nents to be massive. But pistons that weigh 59 pounds each? An 1800-pound turbocharger? How about a crankshaft that weighs 3400 pounds—as much as an entire Olds Cutlass? A fully assembled engine, ready to install, weighs 39,600 pounds. And it’s so big that workmen must perch on six-foot-high catwalks just to adjust the valves.

The scale here is staggering. There’s so much metal to lubricate in a 16-710G3 that the oil pan holds 395 gallons. Keep­ing the engine running at a safe tempera­ture requires a cooling system with 276 gallons of coolant. And your VISA gold card would wilt from just one fill-up; the tank can hold 5000 gallons of diesel fuel. Under full load, an SD-60 gulps 187 gallons of that fuel every hour.

The SD-60’s engine is a direct descen­dant of the powerplant in the original FT103, but it is technologically current. It is a two-stroke, meaning the combus­tion takes place every time the piston reaches the top of its travel. Each cylin­der head is fitted with a single overhead camshaft that operates 32 valves—four per cylinder, all of them exhaust valves. A mechanical fuel injector is located dead center in each combustion chamber.

The huge turbocharger blows pressur­ized air through a pair of aftercoolers (“intercoolers” to car folks) and into each cylinder through several ports located near the middle of each bore; the ports are uncovered when the piston reaches the bottom of its stroke.

The SD-60’s turbocharger, by the way, is also designed to act as a mechanical supercharger. The turbo is so big and heavy that it doesn’t spin of its own ac­cord until the engine is pumping out 75 percent of full power; only then is there enough exhaust flow to budge it. So until that point, a clutch-controlled mechanism drives the turbo off of the crank­shaft—just like a regular supercharger.

We were walking down an open hall about the size of a hangar. A door opened to our left, and a roar issued forth that shook the earth. A man popped out and slammed the door shut. “That’s a dyno cell,” explained Mahalik. “We’re running one of our engines.” We walked down to where the dyno operator was sitting and looked over his shoulder. The engine was turning 903 rpm. “Red­line,” said Mahalik with a nod.

It was hard to imagine so much metal spinning around at all, but spin it did. At 900 rpm, the 16-710G3 was at its power peak, booming out 4100 horsepower. When installed in an SD-60, the hulking V-16 loses about 300 horsepower to accessories—leav­ing 3800 horsepower to drive the generator, which drives the six 1000-hp electric motors that drive the train. You get a better idea of the SD-60’s power when you consider its torque, which measures—get ready for this—23,925 pound-feet at 900 rpm. As much as 65 Corvette ZR-1s.

We went through a couple of doors and everything got quiet; we were in the electrical assembly area. The equipment was still imposing, even if the din was not. “The diesel engine actually turns three generators,” Mahalik explained. The smallest, which weighs a mere 800 pounds, is called the auxiliary generator, and it serves the same purpose as a car’s alternator: Its primary duty is to keep the batteries charged and to provide power to some accessories. It also energizes (“excites” is the technical term) genera­tor number two, called the companion al­ternator. The companion provides pow­er for any AC devices on the train, such as cooling fans, and excites the all-impor­tant main generator.

We checked out some mains being wired up. Their outer rings, called stators, were as big around as the intake on a jet engine, and they contained thou­sands of strands of wire intricately woven together—by hand, not machine.

“The SD-60’s generator makes 9900 amps near stall and 1450 volts at top speed, which for this locomotive is 70 mph,” said Mahalik. When we expressed confusion as to how much power that really was, Mahalik chuckled and launched into the kind of simple explana­tion engineers love to use to illuminate the dim cranial cavities of liberal-arts majors: “We like to say that it makes enough power to light 250 homes.”

Lest those watts, volts, and amps fly out of control and give someone an awful shock, they are carefully managed by a complex computer-aided control sys­tem. These days, virtually every aspect of locomotive operations is, at the very least, computer monitored, if not controlled outright. The SD-60’s three pow­erful microprocessors keep tabs on all diesel-engine parameters and can report, diagnose, and log problems on the move. They watch over the rows of con­tactors that control direction and braking and power flow to the electric motors, determine the excitation of the genera­tors, and manage the SD-60’s advanced traction-control system.

All of the electrical equipment re­quired to put the juice where it’s needed is housed in what’s called the high-volt­age cabinet. We watched as several of these large steel lockers—they’re about as high as a basketball hoop—were wired up. The job looked like an electrician’s nightmare—miles of multicolored wire looping everywhere, thousands of connections, a circuit board the size of two office desks. Later, the cabinets would be installed in the locomotives’ cabs, where they would take up the entire rear wall.

“Everything comes together here,” Mahalik said as we entered the huge fi­nal-assembly hall. At one end, sheet­metal was being fitted to the locomotive chassis, prepped, and painted yellow. A giant overhead crane whirred. “Oh good,” said Mahalik. “They’re going to truck a locomotive.”

At the far end, the crane picked up a freshly painted locomotive, sans wheels, as if it were a scale-model Lionel piece, and hauled it down to where a pair of six-­wheel trucks—the completed axle-and-­electric motor assemblies—sat waiting on a set of rails. Men, some of them in white shirts and ties, stopped to watch. Warning bells clanged. The crane low­ered the locomotive onto its trucks like a loving parent laying their baby in its cra­dle. Trucking a locomotive is always an event, explained Mahalik. A GM car plant might spit out a new vehicle every 60 seconds or so, but LaGrange turns out only one locomotive every couple of days (there’s another GM locomotive plant in London, Ontario).

Time to Drive the Locomotive

“Let’s go drive a locomotive.” Mahalik grinned and held out a pair of engineer’s coveralls he’d scrounged up. Scrounged, because absolutely no one at LaGrange dresses like Casey Jones. Until I arrived, that is. I skulked from the locker room out the back door into the train yard­—red scarf, engineer’s hat, and all, hoping none of the workmen would see me.

Right outside the door was our ride—a spanking-new pair of SD-60s in red-and­-gray Kansas City Southern livery, cou­pled back-to-back. Sitting out in the sun­shine, all alone, they looked . . . big. Really big.

Mahalik waved me up the steps. “Let’s fire it up,” he said. After turning on the elec­trics in the cab, he opened a door at the locomotive’s waist and motioned to­ward me. I twisted the single two-posi­tion switch to prime the big diesel. Then, as instructed, I twisted it the other way, pushed on the manual throttle handle with my right hand and . . . wheeeee, wheeeee, went the starter. Rumba, rumba . . . BAH-RUMBAAAHH. The V-16 lit off like ten semis.

We marched up to the cab, and Mahalik threw the reverser lever to “for­ward” and eased us through the yard at a walking pace. There were rows of dere­lict locomotives parked to one side. “We actually take trade-ins,” he said, nodding in their direction. The cabin was basic: a rubber mat covering the floor, plain dark vinyl on the three bucket seats, gray paint everywhere else.

It wasn’t quite as inhospitable as it first looked, though. These two KCS locomo­tives were equipped with optional air conditioning, electrically heated win­dows, and air-ride seats. A 99-channel two-way railroad radio, a toilet, and a re­frigerator are standard. All of this luxury is yours for a paltry $1.4 million. (Not to worry, there’s no such thing as annual model changes. You can expect your SD-60 to go about a million miles between overhauls and last 15–30 years.)

Mahalik stopped the locomotive a cou­ple of times as several switches were thrown for us. Then we were on what is, quite literally, the test track—a three-­quarter-mile-long private straightaway on EMD property.

“Let’s do an engine self-load test.” He motioned me toward the right seat, the engineer’s seat. The instrument panel angled to my left. It contained gauges for electric-motor current load, air pressure, and brake-cylinder pressure. Jutting out of the panel were levers for the throttle, the dynamic brake, the reverser, the loco­motive’s independent brakes, and another for the train’s brakes. Getting stopped is clearly a high priority in the train business.

Mahalik punched a few keys below the computer display screen on the high­-voltage cabinet behind us. Dozens of green numbers winked on the screen—­engine parameters like coolant tempera­ture, throttle position, generator voltage. The two that interested me were horse­power and rpm.

Mahalik explained that we would be standing still, but the main generator would be on full, providing resistance for the V-16 to work against—like an engine dynamometer. The current manufac­tured by the generator would be routed past the electric motors in the trucks and directly to a huge grid resistor—essen­tially a giant toaster—in the roof of the locomotive. The energy produced by the generator would be dissipated as heat. And to make sure the locomotive’s roof didn’t melt, a 100-hp blower fan would be blasting a gale-force wind across the glowing grid wires.

“The grid resistor is normally used for dynamic braking,” Mahalik explained. In dynamic-braking mode, the electric mo­tors become generators. Now they’re try­ing to resist the train’s movement in an amount roughly equivalent to their pow­er, meaning you have about 5200 horsepower worth of brakes—enough to slow a freight train down in all but hilly terrain. The electricity produced by dynamic braking is spent through the grid resistors.

“Open the throttle,” Mahalik ordered. There are eight throttle positions, and I watched the power readout climb as I notched the big lever through its travel. At position one, the engine was barely awake: only 190 horsepower. By position four, things were getting interesting: 570 rpm, 1310 horsepower. Position five: 1765 horsepower. The noise was getting raucous. Position six: 2280 horsepower and 729 rpm. Position seven: 3350 horsepower, 824 rpm. Position eight-wide open: 3855 horsepower at 903 rpm. But wait, there was more. I saw a flash reading of 4133 horsepower, and the engine settled down to a steady 4055 horsepower. I opened the cabin door. Whoa! Hell itself was bellowing at me. I slammed it shut.

I eased the throttle back to idle. “Okay,” said Mahalik, “now put the re­verser in forward. It’s all yours.” I moved the throttle tentatively. The locomotive crept forward. The view over the stubby hood was surprisingly panoramic. I eased up to 15 mph, then went back to idle. Yeah, that’s it. Like driving a small motel. And we kept coasting. Three­-quarters of a million pounds doesn’t have much interest in slowing down, and the end of the track drew closer. I used the train brake. Ahead lay the main line, and the call of shiny steel rails going off into the distance. Maybe someday.

Going forward was easy, but backing up was something else again. The view rearward was limited by the locomotive body; we were blind to the right. Maneu­vering just the locomotives was unnerv­ing, so backing a freight train around a railroad yard must be a laugh riot.

After a few uneventful trips down the test track, Mahalik suggested we find out what it feels like to pull a load. “I’ll put the rear locomotive into dynamic brake, and we’ll drag it.” Sounded like a megadollar version of “irresistible force meets immovable object.”

It had begun to drizzle, perfect for showing off EMO’s latest traction-con­trol system, according to Mahalik. “Okay, full throttle.” The SD-60 howled and shuddered and shook and began creeping forward. You could feel the traction-control system searching for grip, pulling back the voltage when any of the six driving axles began to slip. “A radar transceiver under the nose, aimed down at the track bed, feeds the comput­ers true ground speed,” Mahalik said over the thrumming. We were going less than 10 mph. “When the track gets really slippery, the computer automatically puts down sand to increase traction,” explained Mahalik, “but we don’t fill our lo­comotives with sand before delivery.

“This is what it would be like dragging a heavy load in hilly terrain. You don’t want to run a locomotive under about 12 mph, because that strains the electric motors and they can overheat.” If more power is needed to get over the moun­tains, a railroad hooks up as many loco­motives as are required, then shuts them down on the flat sections.

Having use of your own personal 4000-hp locomotive wouldn’t be worth much if you couldn’t engage in at least one act of juvenile delinquency, would it? I throttled back to a stop and jumped from the cab. At my signal, Mahalik eased the pair of SD-60s ahead and right on past me. There on the track was my handiwork: a dime and a penny, pressed as flat and smooth as your best shirt. Ah, life is sweet.

“Time to park it,” said Mahalik with a shrug. But wait, Keith, we haven’t done the most important thing of all. Mahalik smiled knowingly and pointed to the big lever atop the instrument cluster. “Go ahead,” he nodded.

Children of all ages, this one’s for you: WOOO—WOOOO—WOOOOOOOO . . . .