ALASKA AIRLINES MD83 SITS AT SEATAC AIRPORT TERMINAL, 2000-08-04 (photo)

The tail and horizontal stabilizer of an Alaska Airlines MD-83 jet (foreground) sits at a terminal at SeaTac Airport in Seattle as another MD-83 taxis past in this February 1 file photo. Alaska Airlines said Aug 3 that it had grounded 18 of its 34 MD-80 jets to check a key component suspected of causing Alaska Flight 261 to crash off the coast of California six months ago, killing 88 people. A tool used to measure vibration caused by wear on the jackscrew controlling the tail-mounted horizontal stabilizer may not have met the manufacturer's design specifications and may have produced false readings. APB/HB/RCS