unmanned drones) to attack convoys of enemy armored vehicles.--Stephen V Cole

The US Air Force is studying ways to improve its AIM-120 AMRAAM missile, the current primary US air-to-air killer. Europe and Russia are pursuing ramjet-powered missiles to get ahead of AMRAAM. Analysts are concerned that delays in a US decision on which way to go in improving AMRAAM could leave the US behind the power curve again. Delays in deciding on how to upgrade the AIM-9P Sidewinder allowed Europe, Russia, and Israel to all field short-range heat-seeking air-to-air missiles that are superior to Sidewinder, and the US is scrambling to field the AIM-9X to regain its traditional lead. The US is already engaged in one set of upgrades for AMRAAM which will be fielded in 2004. These include a new computer and software to be more resistant to jamming. The US doesn't plan to make a decision on how to improve AMRAAM until these upgrades are in place, but is spending $140 million now on various technology development and demonstration projects. The quest for the US, Russia, and Europe is for more range. The US originally planned to build a ramjet powered version of AMRAAM (since ramjets do not need to carry oxidizer for their rocket motors but get oxygen from the atmosphere, they can carry more fuel and have more range) but appears to have dropped the idea because a ramjet-powered missile would be larger and would cut the war load of an F-22 (which must carry its missiles internally to remain stealthy) from six missiles to four. Another option is to package the fuel and oxidizer separately, which would be more efficient and give a few miles of extra range. Raytheon is pushing a dual-pulse propulsion system under which the rocket motor fires several times during its flight and glides the rest of the time, conserving fuel. Another idea is to keep the current missile but write new software that allows it to better guess where the target is going. This would allow the missile to adopt a more efficient flight path and increase the range by as much as 20%. Another idea for AMRAAM is a dual-mode missile that would use a special vector-thrust rocket motor. This would allow the missile to engage short-range targets, and even turn around and attack an enemy aircraft that is