WASHINGTON (AP) - Unmanned aircraft have proved their usefulness and reliability in the war zones of Afghanistan and Iraq.

The Federal Aviation Administration has been asked to issue flying rights for a range of pilotless planes to carry out civilian and law-enforcement functions.

But officials fear that drones might plow into airliners, cargo planes and corporate jets at high altitudes, or helicopters and hot air balloons that fly as low as a few hundred feet off the ground.

Texas Gov. Rick Perry, U.S. Sens. Kay Bailey Hutchison and John Cornyn, and Congressman Henry Cuellar, have been leaning on the FAA to approve requests to use unmanned aircraft along the Texas-Mexico border.

FAA recently approved one request to use the planes along the border near El Paso, but another request to use them along the Texas Gulf Coast and near Brownsville is pending.

Homeland Security Secretary Janet Napolitano says safety concerns are behind the delays. ---

Online:

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