Flaws in K21 Design Confirmed

26 Agustus 2010

K-21's amphibious system (all photos : militaryphotos)

Critical flaws in the design of the K21 amphibious infantry fighting vehicle have been found following an investigation of the up-to-date vehicle, one of which sank during a river-crossing exercise July 29, an official at the Defense Acquisition Program Administration (DAPA) said Wednesday.

A soldier died when the 25-ton vehicle sank. This was the second time that a K21 has sunk since the vehicle entered service last November after 10 years of development.

According to investigators, a pump in the vehicle doesn’t work at its maximum river crossing speed of 7.8 kilometers per hour. The pump is supposed to displace 175 liters of water.

When the vehicle moves at this speed, the pressure inside the engine compartment goes down, and the motor of the pump starts to work. However, it was found that the water was not being removed properly, the official said.

“We plan to look into the design problems with the K21 more thoroughly by the end of next month,” he said. “The final results of the investigation will be announced then.”


The co-developers of the K21 ― the Agency for Defense Development and Doosan DST ― will recall the vehicles once the alleged problems are confirmed, said the official.

The K21 has often been referred to as a key export item in the coming years. Doosan DST and DAPA have said the vehicle offers better firepower, mobility and survivability than the U.S. Army's M2A3 and Russia's BMP-3.

The $3.4 million vehicle is cheaper than the U.S.-built Bradley and German Puma IFV with full options, whose per-unit prices are estimated at between $4 million and $4.5 million, according to Doosan.

The K21 IFV has a 750-horsepower turbo-diesel engine and 40mm auto cannon designed to shoot down slow-moving helicopters and aircraft. It has digital communication, GPS receivers and inter-vehicle digital links.

The vehicle can travel as fast as 70 kilometers per hour on paved roads, and crosses rivers with the help of a Water Jet Propulsion System, according to an Army release.

The South Korean Army plans to acquire about 450 K21s over the next decade.

(Korea Times)