Airline frequent flyer programs, seating, aircraft and computer systems vary widely from airline to airline, which can make redeeming miles or points across programs, or even gaining access to far-flung airport lounges, inconsistent and frustrating.

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The aircraft's computer system did send about four minutes of automated messages indicating a loss of cabin pressure and an electrical failure, officials have said.

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Other aircraft, including the Airbus A380, have had problems during rollout, said University of Dayton professor Raul Ordonez, an aircraft electrical and computer engineer who spent time observing Dreamliner development at Boeing's Seattle headquarters.

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