I finally found the article that I was looking for:
Starting in late 1986 to mid-1987, Boeing looked at simply stretching the current 767. Two fuselage plugs totaling 21' 1" were put in. Total 2-class capacity was @ 300. NOTE: In 1997, Boeing went ahead with this aircraft as the 767-400ER!
Next, Boeing decided to add a new wing as wide as the 747's. Also, they more than doubled the stretch, making the aircraft 226' 8" long, only 5 feet short of the 747. 2-class capacity was @ 340. This design stayed on the boards from the middle of '87 until mid-1988.
767X Aft Double Deck:
Definitely the most radical design to come from Boeing in years, this plane was briefly considered in 1988. Using a modified 767 wing, designers added a simple 9' 2" forward fuselage plug. Then, they slapped a shortened 757 fuselage on top of the aft section of the '67 fuselage. This ungainly bird would have seated @ 355 people, but the design didn't really work.
767X Stretch II:
Using the modified 767 wing developed for the previous version, engineers added fuselage plugs fore and aft to stretch the length to 224' 3". Again seating around 340 in 2 classes, this design stayed on the boards until late into 1989.
Starting in late 1988, Boeing also began designing a brand new aircraft in case the 767X designs didn't meet with customer satisfaction. By the beginning of 1990, it was decided that this new aircraft was the only viable option (at least according to what the airlines were telling Boeing). So all engineering work was turned toward the 777, and the rest is history!
Hope this informs as much as it bored some!
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