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Before the battlefield: Making the Army's Abrams tank

Since 1978, the Army has depended on this proven vehicle, a 70-ton tank with a 120mm gun. CNET's Daniel Terdiman went to Lima, Ohio on Road Trip 2013 to see how the combat vehicle is made.

Since 1978, the Army has made its Abrams tank in Lima, Ohio. CNET Road Trip 2013 checked out how the Abrams is made. Daniel Terdiman/CNET

LIMA, Ohio -- If you were planning an American manufacturing plant for essential military equipment in the early 1940s, you probably wanted to keep it far from the coasts, where the facilities would be most vulnerable to attack.

That was the thinking that led U.S. military decision makers to think of this small western Ohio town as the location for a tank manufacturing plant in 1941. That, and the fact that it is close to the deep-water port of Toledo, Ohio, as well as easy rail and highway access.

Indeed, in 1941, the Army opened the Lima Tank Depot here with plans on making gun tubes. But when the U.S. became embroiled in World War II that December, plans changed, and this sleepy town became home to a major combat vehicle production facility, churning out tanks for the remainder of the war.

After World War II ended, the plant returned to a peacetime footing, only to kick back into gear for the Korean War in the 1950s. Then, when that conflict ended, things slowed down once again.

But in 1978, Lima became home to the Army's nascent Abrams tank program, and until 2001, the plant was devoted solely to producing what eventually became one of America's best-known and most-used combat vehicles. The terrorist attacks of September 11, 2001, changed that, and the plant began turning out other equipment, including the Stryker armored combat vehicle and the Navy's MK46 naval gun system. But still, the Abrams tank is a mainstay of the facility.

As part of Road Trip 2013, I visited Lima for a close-up look at how the Army's main battle tank is made, a fascinating process that in some ways resembles how a car like the Corvette is produced, and that in some ways has all the hallmarks of a high-security military effort.

One of the first things I learned about production of the Abrams -- specifically today's M1A2 model -- is that General Dynamics Land Systems, which operates the government-owned facility, hasn't made all-new Abrams for the U.S. Army since 1996.

Instead, GDLS takes older, decommissioned Abrams and brings their hulls and turrets back to Lima to recondition them, turning them out as new tanks. The older equipment is known affectionately, thanks to the exterior coloration that comes with age and exposure to the elements, as a "Rusty."

Trains from the Anniston Army Depot in Anniston, Ala., deliver the Rusties to the Lima facility, which takes up 396 acres, of which 1.6 million square feet are devoted to production. They are brought inside the main plant and put through a process known as shot blasting, which strips the turrets and hulls of their years of rust and other imperfections. Then they're painted, and the production process begins in earnest.

A completed Abrams turret awaits being married to its corresponding hull. Daniel Terdiman/CNET

For the turrets, the next step is to having a set of ammunition doors mounted. These are a key to the crew's survival in the case of a direct hit by an enemy. The doors are meant to insulate the crew from an explosion by having their panels blow off upwards rather than inwards.

Next, plant workers install the tank's 120 mm main gun, making sure that the vehicle can properly absorb the recoil that comes with firing the gun. And before the turret goes off to an assembly line where a series of additional systems and equipment are installed, workers first mount what's known as "the basket." This is the pod where the gunner, commander, and loader sit, along with about 2,000 pounds of electronics and other gear.

The hull
For the hull, the process is more or less the same. First, there's shot blasting and painting sessions, and then workers put it through one more reconditioning step, known as de-masking and de-taping.

At this point, the hull heads down its own assembly line, at first sitting on the floor because its suspension system has yet to be added. At this stop in the line, known as Station 2, pretty much all of the systems and equipment meant for the hull are installed. This includes things like its gas tanks, hydraulic lines, cabling, and more. This step alone takes about 11 hours, and usually requires two workers to complete.

Daniel Terdiman

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These days, the Lima plant is working at a leisurely pace -- about half a tank per day. But when needed, it can ramp up to about 2.5 tanks a day. All told, the process takes about a week from the time the Rusty rolls off the rail car until cannon installation.

At Station 3, the full suspension system is added. This includes a series of parts like the shock absorbers, the torsion bars, and the road arms and road arm housings -- which hold the tank's road wheels.

Those wheels are added at Station 4, allowing the tank to be lifted off the ground so it can proceed down the line on its own weight. At Station 11, equipment known as the final drive, a gear system that transfers power from the transmission to the track, is added. A large sprocket, which moves the tanks track, is then mounted on top of the final drive.

By Station 14, it's time to install what's known as the full-up power pack, or FUPP. This is a plug-and play package containing the tank's 1,500-horsepower turbine engine, as well as its transmission, and all its cooling systems. The FUPP is designed to be pulled out of an Abrams tank if it is damaged or malfunctioning, and quickly replaced with another. When that happens, the dysfunctional FUPP is taken away and repaired somewhere nearby. Heavy trucks and even airplanes carry additional FUPPs into combat.

The engine itself is meant to give the Abrams' crew an advantage in combat. It can take nearly any kind of fuel, meaning it doesn't depend on any specific type of fuel and can fill up on anything from diesel to peanut oil.

At Station 16, crews mount the tank's track. First they lay two tracks down, bolting one end of each, and then a drag line pulls the tank forward until it sits on top of the tracks. Then a pulley and winch system connects the ends of each track.

At this point, crews have completed what they call a "convertible," a finished hull that's ready to be married with its turret counterpart.

Add some fire control systems, calibrate them so they all work in concert, and the now-finished 70-ton Abrams tank is on to the so-called test and accept building.

There, General Dynamics Land Systems teams put the tanks through a 1,200-point inspection to make sure they're ready for the Army. Those steps can be anything from making sure specific parts are installed (and adding some of them on-site if necessary) to multi-day inspections. There's also about 30 miles of driving the tank around, including taking it up a man-made hill, engaging the parking brake, turning off the engine, and being sure that it can sit there at a perilous angle for a specific amount of time.

After it passes this intensive inspection, the tank is then inspected again, this time by the government's own Defense Contract Management Agency personnel, who subject it to an additional 600 to 700 checks, including driving it around for another five miles or so. All told, all these checks take longer than producing the tank does.

Finally, it's on to "prep and ship," where the government signs off, puts the tank onto a rail car, straps it down, and the Army takes over responsibility for it.

With America's involvement in Iraq over, and the war in Afghanistan ramping down, the call for Abrams tanks has slackened considerably. In fact, the Army itself has tried to stop production, asking to use the financial resources elsewhere. But Congress wants the tank and has continued to fund it. Given the financial problems at the federal level, this is an odd state of affairs. But here in Lima, the continued funding means jobs still exist, and so, day after day, the tanks keep on rolling off the line.