What are some of the myths?
First, let’s dispel some of the earlier myths to the number.
The seventh series of aircraft – Boeing hasn’t built seven different series of aircraft. The first ‘modern’ passenger aircraft from Boeing using jet engines was before the 700 series was the 367-80 (which was a prototype for the 707).
The number of passengers the aircraft can carry – Airbus named its new A300 commercial aircraft after how many passengers it could carry (up to 345). It is unlikely that Boeing would call its first commercial passenger aircraft, the 707, after an ability to carry 707 passengers (the smallest version of the 707 could only carry 181 passengers).
Alas, the real reason is a bit plainer than the above (pun intended!).
The real reason why Boeing uses the 7-7?
It is an identifying number for engineers to defer between different types of products in the Boeing manufacturing line. Here are all the designations:
- 100 for earlier previous models – No longer used but was utilized for the very first biplanes built by Boeing retrospectively.
- 200 are aircraft which did away with the biplane design and have one wing.
- 300 and 400 for commercial propeller aircraft.
- 500 for turbo engined aircraft.
- 600 for missiles and rocket-powered devices.
- 700 for jet-powered aircraft.
- 800 is unused.
- 900 for boats (Yes, Boeing actually built a turbojet hydrofoil called the Boeing 929).
Little did the engineers know at the time that the technology used in the 700 series would become incredibly popular and would overshadow the others.
There is technically another series, the Boeing 2707, but that is a derivative of the jet-powered aircraft designed for supersonic travel.
Why do all 700 series aircraft end with a 7?
A second question to the above is why do all the 700 series aircraft end with a seven?
After all, why is it not:
- 700 vs 707
- 740 vs 747
- 780 vs 787
Hopefully, the above list points out why Boeing made the change. Marketing. It is more attractive on paper to have 7-7 than a simple 700 number. Boeing made all its new aircraft end in a seven for marketing purposes and to stand out from the competition.
What about in the future?
Lastly, there is an interesting point that Boeing has somewhat backed itself in a corner. If we look at the numbers again:
- 707, 717, 727, 757 are discounted.
- 747 is unlikely to have another model number.
- 777 and 787 are new enough that they will continue to have more versions built.
- 737 is arguably either around for a while or has reached the end of its product line and needs to be replaced.
The only number free is the 797 (long rumored to be a new middle of the market aircraft), and beyond that, Boeing has no more numbers. They either need to add a two to the front of its plane (like the Boeing 2707), move beyond a seven at the end of the number (such as 748), or even move up to a new series (Such as a Boeing 800).