Originally Posted by
Semu
I have heard that one of the reasons for the degree of sweep on the 747 was hangar size (more sweep equaling shorter wing span), though I am skeptical. If anyone can documentably confirm or refute I would be grateful.
No documentary evidence, but that sounds very unlikely.
Increasing the sweep while maintaining the same wing span and the same root and tip chord achieves absolutely nothing compared to increased span.
Increased span gives more wing area (more lift) and a higher aspect ration (more efficient lifting). But generally does nothing for you at high Mach.
Increasing sweep at fixed span gives no change in area and worse high lift characteristics but gives better high speed (Mach) drag.
I can't conceive of any circumstances where you'd want more span, and decide to settle for more sweep instead; if anything, they are opposing effects, not complementary.