WASHINGTON, Sept 1: Concern about faulty fuel pumps prompted the US government on Friday to order inspections of more than 1,000 Boeing 737s, 747s and 757s in the United States, the CNN television network reported on Saturday.

More than 3,000 Boeing aircraft are affected worldwide.

The Federal Aviation Administration (FAA) issued the order after earlier inspections on three pumps showed they could create sparks and has given airlines four days to complete the checks. There have been no incidents so far involving the pumps.

The fuel pumps were developed by the firm Hydro-Aire in California and were installed in Boeing machines at the beginning of the year.

Experts fear that wiring on pumps placed too near a rotor could chafe, producing sparks and igniting fumes from highly flammable aircraft fuel.

Meanwhile, Britain’s Civil Aviation Authority (CAA) stressed the directive was a precautionary measure.

“The checks have to be carried out within four days. If there had been an immediate problem it would have been before the next flight. It’s not an immediate grounding,” said a CAA spokesman.

Airlines are being ordered to keep enough fuel in the tanks to cover the devices even when the planes bank or encounter turbulence in flight.

Ron Wojnar, the FAA’s deputy director of aircraft certification services, said submersion would prevent any sparks from igniting fuel vapours and stressed: “This is not an unsafe condition.”

In 1996, the U.S. National Transportation Safety Board ruled that an explosion in the centre fuel tank of TWA Flight 800 caused it to crash off the coast of Long Island.

Vapours in the nearly empty tank probably were ignited by a spark in wiring.

The Paris-bound Boeing 747 exploded in a fireball at 13,700 feet, minutes after leaving John F. Kennedy International Airport in New York. All 230 people on board were killed.

—dpa