WASHINGTON — After a U.S. airstrike mistakenly killed at least 15 Afghans in 2010, the Army officer investigating the accident was surprised to discover that an American civilian had played a central role: analyzing video feeds from a Predator drone keeping watch from above.

Personnel at March Air Reserve Base in Riverside County last year control a Predator drone flying over Ft. Irwin, northeast of Barstow. America's growing drone operations rely on hundreds of civilian contractors, including some, such as the SAIC employee, who work in the so-called kill chain before Hellfire missiles are launched, according to current and former military officers, company employees and internal government documents. (Don Bartletti, Los Angeles Times / January 6, 2010) The contractor had overseen other analysts at Air Force Special Operations Command at Hurlburt Field in Florida as the drone tracked suspected insurgents near a small unit of U.S. soldiers in rugged hills in central Afghanistan. Based partly on her analysis, an Army captain ordered an airstrike on a convoy that turned out to be carrying innocent men, women and children.

"What company do you work for?" Maj. Gen. Timothy McHale demanded of the contractor after he learned that she was not in the military, according to a transcript obtained under the Freedom of Information Act.

"SAIC," she answered. Her employer, SAIC Inc., is a publicly traded Virginia-based corporation with a multiyear $49 million contract to help the Air Force analyze drone video and other intelligence from Afghanistan.

America's growing drone operations rely on hundreds of civilian contractors, including some, such as the SAIC employee, who work in the so-called kill chain before Hellfire missiles are launched, according to current and former military officers, company employees and internal government documents.

Relying on private contractors has brought corporations that operate for profit into some of America's most sensitive military and intelligence operations. And using civilians makes some in the military uneasy.

At least a dozen defense contractors that supply personnel to help the Air Force, special operations units and the CIA fly their drones are filling a void. It takes more people to operate unmanned aircraft than it does to fly traditional warplanes that have a pilot and crew.

The Air Force is short of ground-based pilots and crews to fly the drones, intelligence analysts to scrutinize nonstop video and surveillance feeds, and technicians and mechanics to maintain the heavily used aircraft.

"Our No. 1 manning problem in the Air Force is manning our unmanned platforms," said Gen. Philip M. Breedlove, Air Force vice chief of staff. Without civilian contractors, U.S. drone operations would grind to a halt.

About 168 people are needed to keep a single Predator aloft for 24 hours, according to the Air Force. The larger Global Hawk surveillance drone requires 300 people. In contrast, an F-16 fighter aircraft needs fewer than 100 people per mission.

With a fleet of about 230 Predators, Reapers and Global Hawks, the Air Force flies more than 50 drones around the clock over Afghanistan and other target areas.

The Pentagon plans to add 730 medium and large drones in the next decade, requiring thousands more personnel.

The Air Force is rushing to meet the demand. Under a new program, drone pilots get 44 hours of cockpit training before they are sent to a squadron to be certified and allowed to command missions. That compares with a minimum of 200 hours' training for pilots flying traditional warplanes.

The Air Force also has converted seven Air National Guard squadrons into intelligence units to help analyze drone video. About 2,000 additional Air Force intelligence analysts are being trained.

After the attack that killed the Afghan villagers in February 2010, the U.S. Army Special Operations Command questioned whether civilian contractors had a "potential conflict of interest" in analyzing drone video feeds.

A civilian "might be reluctant to make a definitive call, fearing liability or negative contractual action" if he or she passed on incorrect information that was used to call an airstrike, the command said.

McHale rejected that argument. "Although I recognize that a contractor will have a corporate interest separate and distinct from the military interest, in this instance I found no action or inaction by screeners that negatively influenced the engagement," he responded, according to Pentagon documents.

By law, decisions to use military force must be made by the military chain of command or, in the case of CIA strikes, by civilian officials authorized to conduct covert operations under presidential findings or other specific legal mandates.

Writing in a military law journal in 2008, Lt. Col. Duane Thompson, chief lawyer for the Air Force Operations Law Division, warned that allowing nonmilitary personnel to communicate targeting information directly to pilots would violate international laws of war.

Moreover, civilians are not subject to the Uniform Code of Military Justice, which subjects military personnel to prosecution for war crimes or for violations of rules of engagement on use of force.

"Persons who relay target identification for an imminent real-world mission to persons causing actual harm to enemy personnel or equipment should be uniformed military," Thompson wrote.

The "involvement of civilians in intelligence collection, analysis and planning" is "less objectionable" because it is "further removed" from actual combat, he said.

That involvement is now substantial. In a recent job advertisement, SAIC said it had 450 employees working for the Air Force Special Operations Command and other units analyzing video feeds from the battlefield.

BAE Systems Inc., a U.S. subsidiary of a British aerospace firm, posted an ad seeking an Air Force Special Operations Command veteran to manage "several hundred employees while conducting ISR/FMV missions." ISR and FMV are military abbreviations for Intelligence, Surveillance and Reconnaissance, and Full Motion Video, both of which commonly come from drones.

Michael D. Teegardin, a spokesman for BAE, said the "recruiting ad was for a (Department of Defense) customer, which I cannot name."

Pentagon officials say civilian contractors play a vital role.

"The civilians and the contractors are very important to what we do," said an Air Force colonel, who agreed to discuss the subject on condition of anonymity. "But they're not going to be making a call on any action. They're making an assessment, and that may generate a decision" by a military commander to launch a missile.

A ground-based Air Force pilot is in command of every drone flight and has formal responsibility for any attack.

"Any contractor analysis contributing to operational decisions, such as targeting, must be reviewed" by someone in uniform, said Maj. Eric Hilliard, a spokesman for the Air Force Intelligence, Surveillance and Reconnaissance Agency, which is based at Lackland Air Force Base in Texas.

Contractors are especially common in the CIA, which has used armed Predators to kill dozens of al-Qaida members and hundreds of insurgents in Pakistan since 2008. CIA drones also operate in Yemen, collect intelligence on Iran's nuclear facilities and study other potential targets, current and former officials said.

The Air Force Special Operations Command flies armed drones in Afghanistan, Yemen, Somalia and elsewhere. The command said in a statement that it employs 165 civilians to analyze video and other intelligence. Many work alongside uniformed military personnel in a vast facility at command headquarters at Hurlburt Field.

An additional 300 civilians support other Air Force drones at 10 military bases in the U.S., Germany and South Korea, although most work in technical jobs, officials said. Many are military retirees who kept their security clearances, enabling them to do the same classified work they did on active duty.

After the 2010 accident in Afghanistan, the SAIC employee described her role in a sworn interview with McHale, the chief investigator. Her name was not made public and SAIC declined to identify her. A company spokeswoman, Melissa Koskovich, said Thursday that the woman was still employed by SAIC.

As the mission's "primary screener," she oversaw six enlisted personnel trained in video analysis, including her husband, an active-duty airman. The analysts spent hours that night watching the live video feed as three vehicles neared the U.S. troops.

She condensed her team's observations and her own into minute-by-minute written reports, which she forwarded via a chat system to the Air Force pilot flying the drone from Creech Air Force Base in Nevada. He passed the information to the Army unit in Afghanistan.

Others were watching the drone video, as well. In addition to the pilot, the military crew at Creech consisted of a camera operator, mission intelligence coordinator and a safety observer. A transcript shows they believed the convoy contained insurgents.

The SAIC analyst in Florida was more guarded in her assessment. She reported "military aged males" in the vehicles holding what she described as "possible weapons"; it was impossible to tell from the video what the men were carrying, she said.

"We thought they could have been hostile," she told McHale.

But she also reported seeing children in the convoy. Later, she changed that description and called them "adolescents" after deciding they appeared to be 7 to 13 years old. She also reported at one point that the vehicles had turned off the road and were no longer moving toward the U.S. troops, suggesting that the threat had receded, she said.

The civilian analyst was not in direct communication with the Army captain who called in the airstrike, and she was surprised when she learned later about the attack. But she said it was not her job to second-guess military commanders.

"There have been a lot of times when someone has called out something that was later found to be a mistaken assessment," she told McHale. That's the danger of "real time" analysis, she added.