Milspec Teardown: C-1282 Chaff Controller


A B-52 bomber is approaching its primary target: rail yards in the Beloostrov district of Leningrad. Intel reports the area is likely defended by S-25 Berkut and S-75 Dvinia surface to air missiles (SAMs), but this close to the target the gigantic bomber can’t afford to make the evasive maneuvers, known as combat turns, which would help shake off enemy air defenses. From his position behind the co-pilot, the electronic warfare officer (EWO) reaches over and sets the C-1282 for continuous chaff ejection. Hundreds of thin metallic strips are jettisoned from the B-52, confusing tracking radar and allowing the bomber and her crew to slip through the Soviet air defenses and drop 50,000 lbs of ordnance directly onto the target.

Luckily for all of us, this event never actually occurred. But it was a possibility that the United States and Soviet Union had prepared for extensively. Both sides developed ever more capable weapons, and for each new weapon, a new countermeasure was invariably created. The C-1282 is a component of one such countermeasure, a device that allowed the B-52’s EWO to configure and monitor the bomber’s automatic chaff dispenser. With the C-1282 handling the anti-radar countermeasures, the bomber’s crew could focus their attention on completing their mission.

Of course, as is the case with technology (military or otherwise), the C-1282 was eventually phased out for something new. These old units, now largely worthless, were destroyed or sentenced to a lifetime collecting dust on a storeroom shelf. But through the magic of the Internet, one of these devices is now ready to be laid bare for your viewing pleasure. Dust off your Joseph McCarthy Junior Detective badge and come along as we take a look at a state of the art piece of Anti-Ruskie technology, circa 1960.

Theory of Operation

To be clear, the eBay auction for the C-1282 didn’t include the actual chaff dispenser, much less a B-52 to mount the thing to. This is simply the control unit for the dispenser, giving the operator a way to set the operating mode and monitor the supply of chaff onboard. So as you might expect, there isn’t a whole lot going on inside, but it’s still an interesting example of period hardware.

The C-1282 consists of a counter to keep track of how much chaff is available, as well as a large selector switch not unlike what you’d find on a multimeter. There’s also a signal light to indicate when chaff has been released, and a toggle to enable the system. Interestingly, the device doesn’t offer a way to manually fire off the chaff; presumably such a function must have existed, but was apparently controlled from elsewhere in the aircraft.

On the rear of the device we have two connectors, and between them both, a surprisingly large number of pins. Given this and the style of switch on the front, we can surmise that there probably isn’t much along the lines of actual electronics inside: the switch is simply connecting the different pins to enable various modes. Presumably at least one of the pins will also be used to send the signal that the chaff has launched as well.

Easy Access

A single screw is all that holds on the rear cover of the C-1282, and once that’s removed we can see it features a very open design. Given the age of the device, it’s little surprise that we don’t see any circuit boards; rather, everything is wired point to point. As is also common on these older pieces of gear, most of the connections are soldered instead of using connectors. This was likely considered more reliable, but certainly would make servicing the unit more of a hassle.

Lighting

We take things like tiny PWM controlled LEDs for granted. Back in the day, engineers had to get more creative when it came to something as simple as lighting a panel like the C-1282. The front panel of the device features an internal diffuser which takes the light from three red incandescent bulbs and evenly distributes it. This is best demonstrated by removing the main knob on the front of the device, as you can see the inside of the diffuser on both the back of the knob and the panel itself.

The “Signal” light, which would indicate each time chaff was released, is particularly interesting. This is a light that should be bright enough to get attention, but not so bright as to be distracting or even blinding in the dark confines of the bomber. Accordingly, the EWO had the ability to adjust how bright the light was by turning the knurled top of the indicator.

Turning the indicator opens and closes internal “shutters” that go from nearly complete occlusion of the internal GE-313 bulb to wide open. No electronic dimmers, no circuitry, just brilliant engineering.

The Final Countdown

The counter on the C-1282 is probably the most interesting feature of the device. Labeled as “Chaff Reserve”, this allowed the EWO to see exactly how many countermeasures were remaining at any given time. Interestingly, it must have been somebody’s job to manually reset this counter using the wheel on the left side each time the bomber had its chaff dispenser loaded. Once manually set, each pulse of the electromagnet would decrement the counter by one.

The button on the right of the counter allows the digits to free-wheel, and combined with the gearing used on the adjustment wheel, allows for very rapid spinning of the counter. Considering it goes up to 9999, we have to assume the B-52 was capable of carrying a considerable number of countermeasures. This “rewind” button would definitely come in handy when some poor soul had to reset this counter after an engagement with the enemy.

One has to wonder what would have happened had this counter not been manually reset, or else set incorrectly. Presumably the ground support teams had some kind of checklist to make sure that what the EWO was seeing on his panel matched with what was onboard the B-52 before it left base, but accidents do happen. With modern eyes, this system seems almost comically simplistic; it’s difficult to believe this was deemed acceptable in an application where a failure could literally change the course of history.

Before we move on from the counter, it’s worth pointing out the massive filter that sits between the power pin of the rear connector and the counter’s electromagnet. Presumably it’s there to protect the aircraft’s systems from the potential voltage spike caused by the coil’s collapsing magnetic field each time the counter fires off. Outside of the switches, lights, and counter, this is actually the only electrical component inside of the device.

The B-52 Home Game

Now that we’ve seen how the C-1282 works inside, it should be fairly easy to get it powered up and functioning. The data plate gives us an idea of the safe voltage range to feed it, and the wiring isn’t too difficult to figure out once you start from the electromagnet of the counter and work backwards. Of course we can’t really do anything with the selector switch, but that won’t be necessary to blink some lights and move the counter.

Thanks to the obvious common ground connection to the device’s chassis, half the work is done already. All that’s left is to track the other side of the electromagnet’s coil through the circuit and out to the rear connector. This shows us which pin is used to send the chaff release signal. The last piece of the puzzle was finding which pin in the smaller connector provides power to the C-1282 itself, and we’re in business.

The end result is that the C-1282 is without a doubt the easiest to repurpose piece of military hardware we’ve seen so far. You can easily fire off the counter and indicator light with a relay, and utilizing the selector switch would be as simple as directly hooking the wires up to the digital pins on a microcontroller. As usual, the only limitation here is your imagination. If you can figure out something that can be improved with a real funky looking countdown timer, you’re in luck.

Old Meets New

One of the most interesting parts of doing these Milspec Teardowns for me is seeing these microcosms of top-of-the-line technology from different eras. In taking apart this C-1282 from the 1960’s, I saw traits in common with the WWII/Korean War era CP-142 Range Computer we looked at in the beginning of this series, as well as the AH-64 Apache data entry panel that was in service as late as 2012. Obviously there are some battle-proven design elements that have truly stood the test of time.

It’s not always easy tracking down these wartime relics, but if there are any particular pieces of military technology you’d like to see investigated, let us know and we’ll see what we can do.



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