Why are Boeing airliners designated "7x7"?

Sure, earlier generations of Boeing airliners had model numbers like 247 and 377, but why have they all ended in 7? What does the current leading 7 signify? Will there eventually be a 7107? Will they roll over to 8?

You might find this useful: Google Answers: Boeing Plane names

And no, they seem to have avoided a rollover by calling their Dreamliner the 7E7 (http://www.boeing.com/news/releases/2004/q2/nr_040426g.html) - there’s lots more scope when you start using hexa-hexa-octa-nona-decimal notation. :wink:

The 7E7 Dreamliner is now designated the 787. Just one more to go!

I have also wondered when Nissan will come out with the 1000Z.

That will be a pretty big engine for a two seater sports car.

I’ll let everyone in on a little secret. Boeing’s replacement for the 737 is now called the 7Y7 but will eventually become the 797. Originally scheduled to go into service in 2013, it has been pushed back at least 5 years because of the problems plaguing the 787 plus the 737 is still selling extremely well. This works out great for me, I plan on retiring just before the 7Y7 goes into production. I won’t have to deal with all the crap of putting a new plane into production.

A.D.?

Of course it’s A.D.! There wasn’t anything going on in 787 BC in Britain. In Sumeria, perhaps, but then I’d say “Sumeria, 787…”

In the tradition of leaving no stone unturned around here, I should point out that Boeing did have a jet airliner whose model number did not end in ‘7’. The Boeing 720 (scroll down to “Variants”) was a medium-range version of the 707.

Well, that’s their excuse. The real reason is no doubt that they’ve realized they will have run out of new plane names after the 797 is released, and so are trying to delay it as long as possible.

As to the OP, the 707 was the first successful jetliner. I suspect continuing with the 7x7 was simply a marketing ploy to associate their further jets with that first successful model.

Seems to me Boeing used the number 717 twice, tho’ apparently neither model ever caught on.

Took a few minutes of searching, but I finally found something.

Boeing used 717 for its military version of the 707. The military had its own designations (e.g., KC-135 for the familiar tanker).

The 717 airliner, simply a redesign of the old DC9/MD95, went out of production two years ago after an eleven-year run.

I see. So the designations are all assigned according to a completely consistent, logical formula.

According to a Boeing publication there actually is a reason!

Short answer: the 7x part is an internal product designation, the final 7 is marketing.