US federal aviation officials have ordered emergency inspections on all MD-80 aircraft following last week's Alaska Airlines crash and problems with two more of its planes on Thursday.

In all three cases, metallic debris has been found in the mechanism controlling the horizontal stabiliser on the tail.

The pilots of the doomed Flight 261 complained of problems with the stabiliser minutes before it crashed off the coast of California. All 88 people on board the MD-83 plane died.

The Federal Aviation Administration has given airlines three days to conduct the work.

"We want it done right; we want it done thorough," FAA Associate Administrator Tom McSweeny told reporters.

The order applies to the MD-80s series, MD-90s, Boeing-717s and DC-9s.

There are 1,100 such US-registered planes and another 1,000 worldwide used by about 70 airlines in total. The FAA said it was notifying international authorities of its actions.

Several airlines have already begun checking their fleets following advice from the aircraft maker, Boeing.

The UK Civil Aviation Authority has said there are no aircraft on the UK register affected by the FAA order.

Two Alaska Airlines MD-80s were grounded on Thursday after problems were found with jackscrews - large screws used to hold together pieces of the stabiliser system.

A damaged section of jackscrew with its thread stripped off was recovered this week with debris from the wreck of the MD-83 about 10 miles off the Californian coast.

Click here for a graphic of the last minutes of Flight 261

A spokesman for the American National Transportation Safety Board (NTSB), Ted Lopatkiewicz, said the grounded planes "were found to have metal filings or shavings in or around the horizontal stabiliser jackscrews".

"They are being withheld from service until our investigators can get there and look at them."

Steady flight

The stabiliser, the wing-like structure mounted at the top of the tail, keeps the plane in steady flight and assists in climbing and descending.

Aviation experts say if it was damaged during a flight, the pilots would lose control of the aircraft.

The cockpit voice recorder from the wreckage of Flight 261 revealed that the pilots had problems with the stabiliser after taking off from Puerto Vallarta, Mexico.

The stabiliser went to a full nose down position slightly more than 12 minutes before the plane crashed.

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