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No. 3055:
The Boeing 7X7

Guest post by Andrew Boyd

Today, a plane by any other name. The University of Houston presents this series about the machines that make our civilization run, and the people whose ingenuity created them.

If you've ever flown on Southwest Airlines you've flown on that workhorse of the airline industry, the Boeing 737 — it's the only plane Southwest flies. The plane's been through many changes since it first flew in the late sixties — the Classic Series, the Next Generation series, and now the MAX series — all 737s. So who came up with the name "737"? More to the point, who came up with the naming convention for all Boeing aircraft: a 7 followed by a single digit number followed by a 7?

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Boeing 737 on arrival. Photo Credit: Wikimedia Commons

When Boeing shifted from propeller airliners to jets in the late fifties, it began its numbering anew with the 707. Like pi, it's a number familiar to many engineers: 7, 0 and 7 are the first three digits in both the sine and cosine of 45 degrees. Swept wings — wings that angle toward the back of a plane's fuselage rather than sticking out at 90 degrees — were new at the time. Story goes that the name 707 came from the angle of the plane's wings. It'd be a fitting tale if it was true, but the 707 wing sweep was only 35 degrees, not 45.

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Boeing 707. Photo Credit: Wikimedia Commons

Following the Second World War, Boeing's president organized the company's product lines into blocks of 100. For example, the 600s were reserved for rockets and missiles. Commercial aircraft were assigned numbers in the 700s. The first plane might well have been named the 700, but it just didn't sound right to the marketing Mad Men of the era. "Seven-oh-seven" sounded sexier — with a ring like 'double-oh-seven.' The naming tradition's been carried down over the decades.

Internally, Boeing is noncommittal before an aircraft is released. The 787 started out as the 7E7 — 'E' standing for efficiency, though the 8 seemed predestined. Eight is considered good luck in China, where people will pay substantial sums for items like license plates with 8s. (Recall that the Beijing Summer Olympics began at 8 P.M on the date 8/8/08.) A plane with an 8 in the name certainly couldn't hurt when selling to the expanding Chinese market.

But the 787 also came with another name. Officials at Boeing were prepared to call it the Global Cruiser until it was decided to let the world's population vote on a name. A short list of possibilities was put together and distributed globally. Over half-a-million people from 160 countries cast their ballots. And when the tally was completed, Dreamliner won by a margin of only 2500 votes.

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Royal Dutch Airlines Boeing 787-9 Dreamliner. Photo Credit: Flickr/Woodys Aeroimages

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Boeing 787 Dreamliner First Class Cabin. Photo Credit: Flickr/John P.

And not surprisingly, rumors have already started about the name of Boeing's future planes. Seven-ninety-seven is the obvious choice for the next plane, but what after that? The 807? The 7-10-7? Something altogether different? It's a bridge Boeing will cross when the time comes. But of one thing we can be certain. Given the iconic status of Boeing as America's plane maker, the company will be sure to get a lot of free publicity.

I'm Andy Boyd at the University of Houston, where we're interested in the way inventive minds work.

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Note: No evidence links the naming of the 707 to the fictional British Secret Service Agent 007. However, both the plane and character date to the same period. The first 007 book was released in 1953; the first 707 went into service in 1958. 

M. Lombardi. Why 7's Been a Lucky Number. From the Boeing news website: Accessed March 15, 2016.

G. Norris and M. Wagner. Boeing 787 Dreamliner. MBI Publishing Company, 2009.

J. Wallace. "Boeing 7E7 to Die, but 787 to be Born." The Seattle Post-Intelligencer, December 14, 2004. See also: Accessed March 15, 2016.

This episode was first aired on March 17, 2016