Boeing has secured 496 orders for the B737 Max from five airlines since its August 30 launch.

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It permits an extra aisle, which makes boarding and alighting much faster than on a single-aisle B737.

ECONOMIST: The aircraft of the future

At least then it would have something to battle the B737 when it comes into service in 2008.

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The orders are for 20 of the B737-800 aircraft, 65 of the B737-8 MAX model and 10 of the B737-9 MAX plane.

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As a consequence, the D8.1 would cruise at Mach 0.72 (seven-tenths of the speed of sound) and the D8.5 at Mach 0.74, compared with about Mach 0.79 for a B737-800.

ECONOMIST: The aircraft of the future

If a B737-800 was morphed into the shape of one of the D-series of aircraft on which Mark Drela is experimenting in MIT's wind tunnel, then it would be about the same size, could fly the same routes and would carry a similar number of passengers.

ECONOMIST: The aircraft of the future