The US Central Command in charge of the nearly three-week old war said the F/A-18C Hornet may have been downed by a Patriot missile shortly before midnight last Wednesday.

Since then the navy has declined to provide any details on search efforts, to release the name of the pilot, or to confirm which of Kitty Hawk's three F/A-18 Hornet squadrons he belonged to.

Another airman aboard this aircraft carrier said the possible Patriot involvement explains why officials have stayed quiet.

"They're keeping all that pretty tight-lipped," he said. "That is the reason they are."

The pilot, who asked not to be identified, told AFP that aircrews were told "pretty quickly" that a Patriot may have shot down their colleague.

"We needed to know that," he said.

As a result, pilots are paying extra attention to their Identify Friend or Foe system, he said. The system is supposed to tell a US missile that an airplane is friendly.

The US Army Patriots are designed to defend against hostile aircraft or a tactical ballistic missile attack.

Officials have not responded to written questions from AFP requesting further details on the search effort for the missing pilot.

If a Patriot caused the loss of the Hornet it would be the third friendly fire incident linked to the missile system during this war.

Navy spokesmen aboard this carrier deny that the possibility of friendly fire is the reason senior officers have not commented further.

"I wouldn't characterize it as a reluctance to comment, as it's more prudence in that they do not have any additional information at this point," Lieutenant Brook Dewalt said.

The navy says information on missing aircraft cannot be released while search operations continue.

Lieutenant Commander Mike Brown, another spokesman, said the pilot's family has asked that his name be withheld while he is listed as missing in action.

"They don't want to do anything that might jeopardize the recovery effort," Brown said.

The navy says the crash is under investigation.

Captain Patrick Driscoll, commander of this carrier's air wing, said last week that another pilot saw "a flash in the sky" near the doomed Hornet before it disappeared. Missiles had been seen in the air, Driscoll said.

Officers aboard this ship have said the plane was on a bombing mission when it disappeared in the Karbala region where intense fighting had taken place.

The missing airman's colleagues are satisfied with how the search is being handled, the pilot who declined to be identified told AFP.

"I imagine it's kind of a slow process" because it could be in a combat zone, the pilot said.

Dewalt said Driscoll is monitoring the progress of the search while the entire air wing is sensitive to the issue and hoping the pilot will return.

"A week is an awfully long time. I know that," Brown said. "It's a long time for the person that's waiting to be rescued, if in fact that's the case, as well."

On March 23, the Royal Air Force confirmed that two airmen aboard an RAF Tornado GR4 were killed in action hours earlier as they returned from a mission.

British defence officials said their plane was engaged near the Kuwaiti border by a Patriot missile battery. They identified the dead as Flight Lieutenants Kevin Barry Main and David Rhys Williams, both of IX (B) Squadron.

Two days later, reports said US Central Command admitted an American F-16 warplane fired on a US Patriot missile battery in Iraq after the battery's radar locked onto the plane.

Patriot missiles were deployed during the 1991 Gulf War against Iraq.

On February 25, 1991, a Patriot system in Dhahran, Saudi Arabia, failed to intercept an incoming Iraqi Scud missile that killed 28 Americans.

The US General Accounting Office reviewed that incident and found a software problem in the system's weapons control computer.

Prior to the current Iraq war US defence officials had been developing an updated version of the Patriot.

SPACE.WIRE