Elaborate Safety Measures Failed to Avert Disaster

The downing of two U.S. helicopters by a pair of American warplanes over Iraq occurred despite a host of systems designed precisely to avert that kind of mistake, Pentagon officials said Thursday.

The systems, which have evolved with the march of technology since World War II, range from the simple to the highly sophisticated, and should have begun with a meeting on Wednesday.

Under military procedures, the pilots of friendly aircraft flying within the same hostile zones are to meet the day before to discuss their missions. Once airborne, the pilots could also rely on four different means of radio communication. And finally, the jet pilots could have depended upon visual identification.

As the United States set about the grim task of notifying the families of those killed in the latest incident of “friendly fire,” U.S. military investigators began poring over hours of recorded information from the cockpits of the two F-15C jets and from the nerve center of an airborne command post to determine what went wrong.

It is, for the moment, a mystery.

The circumstances of the downing do little to explain the breakdown. The F-15Cs’ missile attack took place in clear daylight, with an AWACS plane--a sophisticated aerial command post--in control of operations.

It occurred in an area that had seen little Iraqi military activity. As a result, the air crews involved are unlikely to have been in a high state of alert or distracted by enemy forces, as a Navy crew argued had occurred in a previous tragic case of mistaken identity--the downing of an Iranian airliner in 1988 by a missile fired from the U.S. guided-missile cruiser Vincennes.

Moreover, the American commander of the U.N. operation, Air Force Brig. Gen. Scott Pilkington, had checked the safety procedures himself the day before Thursday’s tragic accident--and apparently found all was in order.

“Strange things happen,” said retired Adm. James Winnefeld of the RAND Corp., an expert in the command and control of combat forces, upon learning of the accident from a reporter. “Something like this is the result of a breakdown somewhere in the system. It’s really disappointing because we managed to do Operation Desert Storm so well with many, many more opportunities to blow it. For something like this to happen under these circumstances is a real tragedy.”

Indeed, it appears that several systems set in place to avoid such “friendly fire” failed.

First, Lt. Gen. Richard F. Keller, chief of staff of the U.S. European Command, said the pilots of the AWACS plane, the F-15Cs and the Blackhawk helicopters should have been “tied in tightly” as a result of a meeting that was scheduled to have been held Wednesday.

In that forum, the details of each aircraft’s flight plans--altitudes and times and the radio frequencies they would monitor during flight--should have been coordinated and discussed by air crews that would be in command of planes aloft at the same time.

Keller said that “as a matter of routine,” it is safe to assume the meeting was held.

The Blackhawk choppers were hopscotching from town to town in northern Iraq, carrying senior American, French, British and Turkish military officials and several Kurdish leaders, according to Keller.

Some Pentagon officials suggested the choppers may have deviated from their announced flight plan, or that the AWACS plane and the F-15Cs may have lost track of the helicopters as they made their numerous stops. Under such a circumstance, the F-15Cs and AWACS plane could have failed to recognize the choppers when they reappeared on their radar.

But had that happened, the pilots of the F-15Cs, as well as their controllers aboard the AWACS plane, should have had other means of determining identity.

First, the Blackhawks, like all aircraft not directly engaged in combat operations, should have been broadcasting a continuous signal of identification over an international civil navigation frequency. This “squawking” signal alone could have tipped off the combat aircraft to the choppers’ identities.

Beyond that broadcast, the F-15Cs or the AWACS plane had three other electronic signals that they could have used to confirm the choppers were friendly. The Air Force planes should have been able to use a sophisticated “identification friend or foe” system that sends out an electronic “Who goes there?” query. The Army helicopters are equipped with corresponding systems designed to respond automatically with a friendly identification message.

But the systems must be turned on, operating correctly and accurately programmed. Under conditions of military tension, including those that may have existed above Iraq on Thursday, an aircraft may be presumed hostile if it fails to respond affirmatively to such a challenge of a fellow aircraft.

The “identification friend or foe” system now in use aboard U.S. warplanes can operate in any one of three electronic modes, all of which should have been available to all the aircraft involved in Thursday’s incident.

Military experts, including an experienced F-15C pilot, on Thursday said they were mystified that none of the four electronic procedures designed to elicit the choppers’ identity as “friendly” revealed that vital information.

Finally, there is the most low-tech means of identification: the eyes of the two F-15C pilots, who are trained to recognize most enemy aircraft.

Keller pointed to one feature that may have helped deceive the pilots--the Blackhawk helicopters were carrying external fuel tanks to extend their range; those pods appear to heighten similarities between the Blackhawk and Soviet-made Hind helicopters flown by the Iraqi air force.

Procedures such as the electronic signaling that should have taken place Thursday helped U.S. military and allied aircraft in the Persian Gulf War operate without a single “blue-on-blue,” or “friendly fire,” casualty. That was the case even though hundreds of dissimilar aircraft from several countries and many different services operated in close proximity to one another.

By contrast, “friendly fire” claimed dozens of casualties among ground units in the Persian Gulf; those units operated in the confusion of fast-moving tank battles without benefit of identification systems as sophisticated as those used by allied warplanes. In the wake of the Gulf War, an Army-led working group has sought to improve the procedures and the technologies used to distinguish friend from foe.

Safety Beacons in the Sky

U.S. aircraft in the region are equipped with “identification” friend or foe systems” that are supposed to alert pilots that they are dealing with American aircraft.

Beacons at Work

1. The devices receive and transmit constant electronic pulses.

2. If a U.S. aircraft wanted to double-check an aircraft’s identity, it could send a pulse that would query the aircraft.

3. A device would then provide a visual indication that they were being “queried,” and would automatically send back a signal indicating they were friendly.

What Went Wrong?

It is possible that one or all of the systems were not working right, or they may simply not have been turned on.

Source: Times Washington Bureau, wire reports