WASHINGTON -- Iraq has developed a new type of high-explosive weapon capable of delivering a devastating blast similar to a small nuclear explosion over an area several miles wide, Pentagon officials say.
The weapon, known as a fuel-air explosive, is particularly effective against air bases, oil fields and troops in the open, military experts said. Unlike Iraq's arsenal of chemical and biological weapons, there is no ready defense against this type of device.
"It's not your garden-variety weapon," said Henry Sokolski of the Pentagon's international security affairs office. "These are blast-effect weapons, and what you can't see can kill you."
Concern is mounting about the threat that the exotic explosive, which the United States does not have in its arsenal, poses to U.S. troops in the Persian Gulf.
Five senators, including John Glenn, D-Ohio, and Jesse Helms, R-N.C., have sent a letter to Defense Secretary Dick Cheney asking for an investigation of the size and sophistication of Iraq's supply of fuel-air explosives and whether U.S. technology was used in the weapons' development.
Earlier reports have indicated that the know-how for building these bombs was supplied to Iraq indirectly through the German arms industry. But a congressional investigator said that U.S. technology may have been involved as well.
Fuel-air explosives, FAEs, are a kind of gas bomb involving two detonations. The principle is similar to filling a room with natural gas, then tossing in a match.
The bomb or missile warhead contains fuel, usually propane or ethylene oxide. An initial explosion disperses the fuel into the air. A second, time-delayed detonation ignites the mixture of fuel and air, creating a huge fireball and shock wave.
The invisible shock wave is similar to that of a tactical nuclear weapon and spreads rapidly across a wide area. The shock wave is capable of flattening buildings, destroying aircraft, knocking down oil rigs and killing troops, Pentagon experts said.
At peak efficiency, FAEs have destructive effects 10 times more powerful than conventional explosives of the same size, the Pentagon estimates. Even the least efficient FAE, if ignited correctly, has double the explosive yield of a normal weapon.
An analysis by U.S. intelligence officials indicates that the weapon's effectiveness against personnel has been underestimated by the Pentagon. In addition, the analysis said that the FAE is especially potent in clearing mine fields and destroying fuel depots, ammunition supplies and radar vans.
FAEs can be launched as bombs from airplanes or as warheads on missiles. Missile-delivered FAEs would be the most difficult kind for U.S. forces to defend against. But Pentagon officials said there was no clear evidence that Iraq was capable of mounting the devices on missiles.
But one military analyst said, "There is nothing magical about putting these things on rockets or missiles."
Iraqi President Saddam Hussein has mounted an intensive international campaign in recent years to buy sensitive Western technology to develop a variety of weapons, including long-range ballistic missiles capable of carrying FAEs.
Western analysts do not believe that Iraq possesses accurate, long-range missiles. But a Pentagon analyst said that the far-reaching power of the FAE made it especially well-suited to compensate for the presumed inaccuracy of Iraqi missiles.
There seems to be little doubt that Iraq possesses FAEs. At an arms show in Baghdad in April 1989, Husayn Kamil, the head of the Iraqi Military Production Authority, displayed one of three types of FAEs that he said the country had produced.
Pentagon experts said that technical information about FAEs has been distributed widely throughout the world. The weapons are in the arsenals of the Soviet Union, Israel, China, France, Germany and Spain and may be possessed by Third World countries in addition to Iraq.
In the early to mid-1980s, the United States investigated fuel-air explosives as a means of reducing its reliance on nuclear weapons. But it has not developed an arsenal of the devices.