NELLIS AIR FORCE BASE, Nev., March 30 - In the skies over Iraq, the number
of remotely piloted aircraft - increasingly crucial tools in tracking
insurgents, foiling roadside bombings, protecting convoys and launching
missile attacks - has shot up to more than 700 now from just a handful four
years ago, military officials say.

As the American military continues to shift its emphasis to
counterinsurgency and antiterrorism missions, the aircraft are in such
demand that the Pentagon is poised to spend more than $13 billion on them
through the end of the decade.

The aircraft are being put into service so quickly that the various military
and intelligence branches are struggling to keep pace with the increased
number of operators required and with the lack of common policy and strategy
on how to use them.

There are nearly a dozen varieties in service now, from the 4.5-pound Ravens
that patrol 100 feet off the ground to the giant Global Hawks that can soar
at 60,000 feet and take on sophisticated reconnaissance missions. And while
much of the appeal of the aircraft is that they keep aircrews out of the
line of fire, there are now so many of them buzzing around combat zones
that, in fact, the airspace can get dangerously crowded.

In November, for example, a tiny Army Raven surveillance aircraft plowed
into a Kiowa scout helicopter, causing no injuries or serious damage, but
raising safety concerns.

Army officials insist that it was an isolated case, and cite tighter flight
procedures and the addition of strobe lights to smaller aircraft since then.
But other military officials have noted several near misses.

"What it shows is we've got to make sure the lack of control of the airspace
and the separation of these things doesn't contribute to disasters of these
things hitting one another," Gen. John P. Jumper, the Air Force chief of
staff, said about the November accident in an interview.

Never before has the American military used so many remotely piloted
aircraft in such diverse missions, and many officers call them the wave of
the future.

At a command hub spread among a half dozen dimly lit trailers at this air
base just off the Las Vegas Strip, the future is now. Small teams of
remote-control warriors nudge joysticks to fly armed Predator aircraft 7,500
miles away. Once the Predators take off in Iraq or Afghanistan for missions,
the air crews here take over.

The Predator, which can carry Hellfire air-to-ground missiles, is the
best-known of the remotely piloted fleet. It is an ungainly,
propeller-driven craft that flies as slowly as 80 miles per hour, and can
loiter continuously for 24 hours or more at 10,000 to 15,000 feet above the
battlefield.

In each trailer, a pilot and co-pilot , who operate the Predator's zoom
lens, radar and infrared sensors, sit side-by-side before an array of
consoles and computer screens that let them see what the Predator sees while
they talk to troops on the ground by radio or e-mail. Soldiers and ground
spotters can receive live video images from the Predator on specially
equipped laptop computers.

"I can watch the rear of a building for a bad guy escaping when troops go in
the front, and flash an infrared beam on the guy that our troops can see
with their night-vision goggles," said Maj. John Erickson, 33, an F-16
fighter pilot who has spent 18 months in a stationary cockpit here.

Commanders say the aircraft have played a pivotal role recently by attacking
insurgent mortar positions and warning convoys of suspicious roadblocks that
could be ambushes. To bury roadside bombs, insurgents often douse the street
with gasoline, ignite it, and dig up the heat-softened asphalt to lay the
explosive. The Predator heat sensors detect the hot strips, and warn nearby
troops, military officials said.

Predators are also a weapon of choice for the Central Intelligence Agency.
Hellfire missiles launched from a Predator three years ago destroyed a car
in Yemen, killing an operative of Al Qaeda and five other occupants inside.
Last August, the United States secretly deployed a new version, a bigger,
faster and more heavily armed model called Predator B, for the C.I.A. to use
in the Middle East, administration officials said.

With every commander clamoring for a bird's-eye view of the battlefield, the
24-hour operations are putting strains on the aircraft and their operators.
In just the past week, two $5 million Predators crashed near their base
north of Baghdad, bringing to 25 the number that have been lost in Iraq and
Afghanistan to storms, pilot error, enemy fire or mechanical failure since
the Sept. 11 attacks, the Air Force said.

The Air Force is steadily training new Predator pilots and sensor operators
at a desert base 45 miles northwest of here. But Maj. Gen. Stephen M.
Goldfein, the air warfare center commander here, said he has only about half
the Predator pilots he needs, and he worries about the stresses that the
eight-hour-a-day, six-day-a week job puts on them.

Moreover, the Air Force announced last month that it was adding 15 new
Predator squadrons to the three existing ones.

In Washington, a fierce competition has erupted among the Army, Navy, Marine
Corps and Air Force over which will take the lead in coordinating the
military's policy and strategy involving unmanned aircraft. The Joint Chiefs
of Staff met twice in the last week to discuss these sensitive decisions and
to underscore the need to set aside rivalries and streamline the flow of
information to troops.

A new report by the Government Accountability Office, an investigative arm
of Congress, warns that planning in the Defense Department has failed to
keep pace with the rapid development and fielding of remotely piloted
aircraft.

"D.O.D. still lacks a viable strategic plan and oversight body to guide
U.A.V. development efforts and related investment decisions," said the
report, issued on March 9. It said a Pentagon task force created to address
these issues has limited authority and no enforcement power over programs.

Between 750 and 800 remotely piloted aircraft are operating in Iraq and
Afghanistan, with a vast majority in Iraq, two military officials said.
About two dozen of the Air Force's 58 Predators are flying in the two
countries, officials said. In the battle of Falluja and surrounding areas
last November, Predators fired about 40 Hellfire missiles. One Global Hawk
operates in the Persian Gulf region.

In addition to these aircraft, the Marine Corps is flying 100 aerial
vehicles in Iraq, including Pioneers and Dragon Eyes. The Army is flying
hundreds of Ravens, as well as larger Shadow, Hunter and I-Gnat aircraft.
"We're flying the wings off it," Lt. Col. Stephen K. Iwicki, a senior Army
intelligence officer, said of the Hunter, which will soon be armed with a
small, laster-guided explosive called viper strike.

While some pilots in Iraq express concern over sharing airspace with the
remotely piloted aircraft, they are proving popular with ground troops. Sgt.
Rowe Stayton, who just finished a stint as an infantry fire-team leader in
northern Baghdad, is a booster for the Raven, in particular. He recalled one
incident where the aircraft tracked some suspected insurgents after they had
dug up something and put it into a vehicle. Troops later seized the vehicle
and found it full of mortar tubes and rounds.