What’s the deal with all Boeing planes ending in the digit 7? The story of this mega plane began after World War II when Boeing was still a military airplane company. Boeing president, was William Allen, decided to expand their planes into the commercial avenues along with pursuing the fields of missile launch and spacecraft. So they needed to divide the model numbers into blocks of 100 for all the diverse products, 300s and 400 were reserved for aircraft, 500s for turbine engines, 600s for rockets and missiles and 700s were to be used for jet transport aircraft.
The B-47 was Boeing’s and the world’s first large swept-wing jet that caught the eye of every other airline company. Boeing was simultaneously working on remodelling the propeller-driven 367 Stratotanker, also known as the KC-97, into a jet-powered one that would be compatible with the B-52 during in-flight refuelling.
The nickname of “Dash 80” was given after several iterations of model 367, finally giving it the version number 367-80. This plane was financed entirely by Boeing itself as they wanted to sell the plane as both a Air Force tanker and commercial transport. But both of them were offsprings of Dash 80, so the model number was given a number in the 700s to differentiate between the two. “Model 700” was found to not have a good ring to it, so they named it Model 707 since it seemed a bit catchier. The other model of the Dash 80, the Air Force tanker, was allotted model number 717 along with the military designation of KC-135.
But 717 was the only military plane ending in the digit 7 since the marketing department soon decided to name all remaining and future commercial models that began and or ended in 7. Even the model 717 was reused to name the MD-95, which is part of the Boeing commercial jet family, after the Boeing-McDonnell Douglas merger in the late 1990s.
So that is why every airplane’s name now ends with 7. Pretty interesting, isn’t it?