Another “What did you do in the war, daddy?” post.
As I’ve explained in previous articles ( see the “War Stories” category on the sidebar if you’re interested) I spent some time in the Army as an armor crewman instructor at Fort Knox, Kentucky, 1972-1973. This little story is about night driver training.
The military finds it useful to move around at night, but in most situations, they don’t do it with headlights like you have on your car. That’s the trick. After a few hours of bounding over the terrain of the driver training area, just about anybody could drive a tank at night using headlights. The thing we had to teach, though, was how to do it under “tactical”, i.e., combat conditions.
Now you have to remember that this was thirty years ago, and it was not expected that our enemies would have all the night vision equipment that is used today. This equipment makes a lot of these techniques of little use. More about that later.
At the time I was an instructor, we had two different tactical modes for driving, visible and infrared. For visible mode there were two choices. In “blackout drive” mode, the front of the tank had a little “blackout” headlight. This was shielded so that almost no light was visible from above, and it illuminated the terrain ahead about as well as an old two-cell flashlight. If (big if…) the driver’s eyes were adapted to the night, he could see just well enough to avoid major disruptions in the terrain. To help that night vision, the interior lights of the tank were lit with red light, very dimly, as this supposedly had the least effect on night vision. In pure “blackout mode”, you didn’t even have that sad little light. You had to depend on what visual references you could glean.
Every military vehicle had this “blackout” headlamp. Each vehicle also had “blackout” tail lights. These were cleverly designed. Each of the two tail lights on a vehicle had a pair of “cat eyes”, two closely spaced pairs of red lights. The clever part was that if you were too close to the vehicle ahead of you, you could see each of the lights of each pair, so a tail light would show you four lights. Too close. You backed off, and the four lights dissolved into two lights on each tail light. You were now at the correct distance for convoy. Slow down too much, and the two lights you were seeing at the proper distance would dissolve into ONE light on each tail light, and you knew you were too far back. It was simple system. And that was ONE thing we’d practice on our night driving session.
The second mode was infrared driving. Remember, this was before night vision devices were available for driving. We used active infrared. “Active” means we shined an infrared light to see with the proper equipment. Each tank had on its headlight assemblies, one on each side, an infrared headlamp. This was no more than a regular headlamp hiding behind an infrared filter which looked like opaque black glass. The driver could select the different headlight modes from a selector switch in his compartment, choosing off, blackout, blackout drive, IR or visible (normal) operation.
Since the infrared light was invisible to the naked eye, the driver had to use a special device to see it in order to drive. This was the infrared driver periscope. This thing weighed around ten pounds and was made be installed in a special swiveling periscope port in the armored driver’s hatch. The drill was that you dropped the adjustable driver’s seat down so that your head was below the rim of driver’s hatch, and then closed the hatch. This was the “buttoned up” mode. Now, in daylight or when using visible modes, you could drive while buttoned up by peering into three “vision blocks” or periscopes spaced around the hull just outside the hatch. These gave you a field of view of about 45 degrees to either side. It was limited, but with a bit of practice, it wasn’t bad.
But let’s get back to this IR (infrared) thing. The driver would button up, then stick this periscope up through the port in his hatch, and adjust it so he was level with the two eyepieces. Then comes the fun part. This bit of 1960’s technology required 10,000 volts to operate. Yes, 10 kV. We had a high voltage power supply in the tank that took the 24-volt DC system and bumped it up to 10,000 volts that went through a cable as thick as your finger. It had a connector to make up to a receptacle on the bottom of the periscope, and when plugged in, the connection was secured by screwing a collar up to hold it in place.
That was part of the class we taught. I would get myself into the driver’s seat, and the three trainees would be peering in at me from inside the turret. I would demonstrate how to mount the periscope, point out the controls on the periscope for focus, show how it would swivel (reluctantly) from side to side. Then I’d remove the connector end of the high voltage supply cable from its neat little storage plug. And while holding it where they could all see it, I’d flip the switch to turn on the power supply. And inside the open plug, that 10,000 volts would start making a loud blue arc. This demonstration was meant to hammer home the next step. I’d turn off the high voltage, then insert the end of the cable into the periscope, screw the collar down to secure it, and THEN turn on the power to energize the periscope. After I’d demonstrated it, then each trainee in turn would get into the driver seat and go through the steps, mounting, connecting the cable, turning on the ‘scope, and looking through it.
After all the instructors had finished that block of instruction, it was time to practice. In the driver training area we had a road about a half a mile long traversing the training area. It was dark outside. First trainee driver gets in the driver’s seat on each of fifteen tanks. The field first sergeant gets in his jeep and we form a column behind him. We go from one end of the road to the other, using blackout lights. The trainees get to see those little cat eye tail lights at work as they learn to maintain column interval in the dark. It’s not easy for them and the column accordions back and forth as they struggle to keep the proper distances. We get to the assembly area at the other end of the road. Somebody passes the IR periscope to the driver and he installs it just like we discussed and trained, and the column turns around and goes back the other way.
The process is repeated with the second driver. Same thing. I’m up in the commander’s hatch, offering commentary and advice over the intercom to the driver. And we successfully make the trip again.
Last trainee of the night. This one is, shall we say, not the sharpest knife in the drawer. Good kid. Means well. Tries hard. He’s in the driver seat. I do the intercom check with him. The radio crackles for us to move out, and we do. The fitful light of the blackout headlight barely lights the road. The cateyes of the tank ahead of us lead us off into the impenetrable dark. a little while later, we’re across the training area.
One of the other trainees hands over the IR ‘scope. I talk the trainee through installation. The call comes over the radio, and we move out. From the tank commander’s position, IR driving is eerie. Now I don’t even have those cateyes or that miserable little blackout light to see. No moonlight comes through the overcast clouds. It’s totally dark. Well, we’ve made this trip twice already tonight. Soon we’d be back at the other end and putting the tanks to bed for the night.
Over the intercom I asked, “Can you see everything okay?”
“Sarge,” he said, “this is neat. It’s all greenish, but I can really see.” He had seen what I’d seen earlier as he watched one his buddies’ trips from his own position looking out of the loader’s hatch. It was high-tech stuff when ‘hi-tech’ meant an eight-track in your car.
“Okay. Now just like we learned. You see the guy ahead start to pull away, just make a little correction on the throttle. He gets too close, just back off the throttle a little. Small corrections keep us from accordioning.” I passed on the lessons that needed to be passed on.
“Roger,” he said. We rumbled on. We were about halfway when it happened. The road we were on was elevated, about four feet higher than the terrain on either side. I heard the driver scream over the intercom and the tank jerked hard left, over the edge of the road and over that four-foot drop. I grabbed on as soon as I felt the lurch and held on hard as we went over the edge. He was still letting loose short, piercing screams. The tank cleared the embankment and rolled about thirty or forty yards before it came to a stop against a hillock, engine idling. And driver still screaming.
As soon as we leveled out, I dropped from the commander’s position down to the turret floor so I could get to the driver. He was going through convulsions, kicking and screaming, and I saw (and heard) what the problem was. I reached into the driver’s compartment and flipped the switch, killing the high voltage supply. Finally, the cable lay quietly in his lap, dead.
“Didn’t screw the collar up, did you?” I asked. He didn’t say anything. I knew he wasn’t dead. His shoulders were heaving with his frantic attempts at breathing.
Finally he got under control. “That thing fell out of the periscope and hit me in the crotch, ” he said, stating the obvious. “I couldn’t get out of the way.”
I surveyed the rest of the crew. The trainee in the gunner’s seat was rubbing a shoulder he’d bumped during the ride down, and the kid in the loader’s hatch was rubbing his ribs.
The radio crackled. “Four-two, four-three, what’s your problem?”
“Ah, this is four-two. Driver had a little experience with the IR cable,” I reported.
“This is four-three. My driver followed four-two off the road.” My fellow instructor’s driver had made this a “two-fer”.
“Everybody okay?”
“Ah, affirmative. And a LOT more experienced. We’re going to hook stuff back up and get back on at the end of the column.” I looked at our young hero. “Well, hook it up again. ”
His face was still ashen as he gingerly picked up the cable.
“Hell, it ain’t gonna hurt you now. ‘Sides, you should be immune. And screw that collar down tight.” I watched.
I climbed back up into my hatch, flipped the intercom switch, and said “Pull back up on the road after the last tank. Remember, when you go up the bank, you’re going to have to feel for it, ‘cuz you won’t be able to see.”
He voiced assent. The last tank passed us as we turned back toward the road. I could hear it but not see it. I keyed the intercom. “Move out, driver.” And the engine rumbled as we moved forward. I felt the tank surge up the rise and onto the road. As it leveled, I told the driver to turn right and we lined up, headed back to the assembly area.
Keying the radio, I called the other tank. “Four-three, this is four-two. Wanna follow us back onto the road?”
“Sure, why not. We followed you down here.” My buddy in the other tank was a comedian.
We got back to the assembly area without further incident. After we got the tanks secure for the night, the field first sergeant brought my unfortunate trainee up in front of the platoon and let him tell what happened, thereby emphasizing the importance of following procedures.
His buddies nicknamed him “lightning”.
Today’s technology makes the IR driver periscope obsolete. After all, it needed IR light to see, and somebody figured out that if WE could invent an IR periscope, the other guys could invent IR equipment to see our headlights as well. But it was cool stuff at the time…