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.

WSJ: Microsoft Co-Founder to Build Massive Jet for Space Launches

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

WSJ: Pilot Blamed in 2011 Crash of Helicopter

In 2003, the issue of passenger weight surfaced when a commuter plane crashed on takeoff from Charlotte, North Carolina, because of excess weight and a maintenance error.

CNN: Airline policies juggle larger passengers

According to the report, Mr. Nicholson told investigators that Mr. Dudley did not ask the passengers' weight or perform any calculations before takeoff.

WSJ: Pilot Blamed in 2011 Crash of Helicopter