Mike said he didn't feel comfortable talking about his identical twin Mark, who died on United Airlines Flight 175.

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She was slated to be on United Airlines Flight 175, headed out that morning to an event in Los Angles, where she was supposed to address the audience.

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Seventeen minutes later, United flight 175 hit the south tower.

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Fuels savings by reducing weight is significant when you include the two pilot bags (50lbs), Cockpit Manuals (25lbs), and Flight Attendant Manuals ( 4 x 25lbs) that the iPAD will eventually replace. 175 lbs is the weight of a person.

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