Hamburg - The "Patriot" weapons system is designed to protect against both airplane and missile attacks.

In the US-developed system, each unit consists of eight mobile launching ramps, each with four rockets.

Complete with launching ramps, radar and control station, the system is mounted on lorries. It can detect several targets simultaneously, but its effectiveness is, however, a matter of dispute.

The up to 5.3-metre-long rockets have a diameter of 41 centimeters and weight about 900 kilograms. A newer version of the system features rockets with a smaller diameter and weighing 312 kilograms.

The rockets achieve a velocity of almost four times the speed of sound and can strike targets at altitudes of up to 30 kilometers and a distance of more than 100 kilometers.

When it was introduced in 1982, a Patriot rocket cost about 700,000 dollars. The system was put into action in the 1991 Gulf War, in the skies above Saudi Arabia and Israel, to protect against Iraqi "Scud" missiles.

In 2003, Patriot rockets were positioned in Turkey. In 2006, as North Korea began its missile tests, Japan also began installing the Patriot system. (dpa)