Expected to weigh roughly 1.2 million pounds, the combination would roughly match the maximum takeoff weight of the largest, fully loaded Airbus A380 superjumbo plane, but the wings would be more than 120 feet longer than those of the Airbus A380.

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The maximum allowable weight at takeoff for the helicopter, a BELL 206B, was 3, 200 pounds, the report said.

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