The U.S. Army is trying to design a replacement for its M-2 Bradley IFV (Infantry Fighting Vehicle). The new vehicle is the GCV (Ground Combat Vehicle), and it's getting a cool reception from Congress. The politicians smell another boondoggle, that will take forever, promise too much, cost more than anyone can afford and ultimately be cancelled. The army is setting the bar high. They want a vehicle with greater firepower than the M-2, the mobility of the Stryker and the protection of an MRAP. This is seen as unreasonable, and a bad sign. Congress is trying to persuade the army to scale back its ambitions, and learn from existing new designs. The Bradley design is over three decades old, although there have been many upgrades. But some existing designs show promise.
U.S. Marine Corps new EFV (Expeditionary Fighting Vehicle), recently underwent tests to see how it would hold up against roadside bombs. It was found that the EFV had similar survivability characteristics to MRAPs, when hit with roadside bombs or anti-vehicle mines. The EFV weighs nearly 36 tons, is 3.4 meters (10.5 feet) tall, 3.9 meters (12 feet wide) and 9.6 meters (29.9 feet) long. It's armed with a 30mm automatic cannon (MK34 Bushmaster) and a 7.62 mm co-axial machine gun. The EFV has been over a decade in development, and has had a lot of problems, most of them to do with the water propulsion that moves the vehicle at high speed (60 kilometers an hour) towards the beach. Take away this, the EFV would probably be in service by now, and not be costing $22 million each. But the EFV is larger than the M-2, and built to carry 17 passengers (in addition to the crew of 3), rather than six. That large bulk may have something to do with the MRAP like resistance to bombs and mines.
Another recent design worth looking at it the South Korean K-21 IFV. The 26 ton vehicle is similar to the 33 ton U.S. M-2. The K-21 has a crew of three and carries nine infantry in the back. The two man turret carries a 40mm autocannon, with 200 rounds, as well as two ATGM (Anti-Tank Guided Missile) launchers and a coaxial (with the 40mm) 7.62mm machine-gun. Top speed is 70 kilometers an hour.
The big difference between the K-21 and M-2 is weight, and that is mainly because the chassis of the K-21 is made of fiberglass. This material is as strong as metal, but much lighter. Armor protection of the two vehicles is equal. The K-21 armor can stop 14.5mm bullets and most artillery fragments (it is vulnerable to 152mm shells exploding closer than 10 meters, but at that distance, the blast effect would do serious damage).
The 40mm autocannon fires up to 300 rounds per minute, at speeds of 1,000 meters per second (3,100 fps). The anti-tank round can penetrate up to 220mm of armor. The 40mm can also fire a multipurpose shell, where the gunner can select proximity (exploding close to a target), air burst (exploding above the ground), as well as armor-piercing or fragmentation effect. Such a 40mm weapon has already been suggested for the GCV.
Like the M-2, the K-21 carries an extensive load of electronics, for fire control, navigation and diagnostics. The K-21 designers learned from other recent IFV designs and attempted to improve on their best characteristics. The K-21 costs less than $3 million each. But the K-21 is not expected to have much more protection from roadside bombs than the M-2. This may prove to be an intractable problem, given that the MRAP gets its protection from its V shaped underside, specific design elements that cannot be incorporated in a vehicle like the K-21. The American legislators fear that the army will spend a lot of money looking for a solution that doesn't exist. It's happened many times before.