>if one were to print out a compleat set of blueprints/specifications and try to load them into one, it would probably be too heavy to take off.

This expression might actually have it's origins in the 747. I've heard in aerospace that "you don't fly until the paper weighs more than the plane"

Pretty sure that's a much older expression and is more in reference to exhaustive paperwork and maintenance documentation.

Considering the 747-400 carried 1,000,000 pounds (453,592.37 kilos) to cruising altitude, that might be in dispute.

Hyperbole can be like that.

Still, it was an interesting factoid, and by all accounts, the redundancy of the technical documentation (multiple drawings of bolts depending on which system they were used for, which grade/alloy/coating was specified) edges it towards believability.

Expanding on your point, a while ago I read a great book on 747 development (by Joe Sutter, who was the lead engineer for the 747) and one surprising thing for me was that Boeing was very much into the supersonic race at the time. The SST project was Boeing's darling. As such it got the top-ranked technical talent assigned to the project, as well as the best tools, management oversight, etc. In contrast, the 747 dev teams got pretty much less of everything, including being dispersed over a large area of corporate buildings. Despite all of that, it still succeeded beyond anyone's expectations at the time.

Thanks!

Added that to my "Want to read" list on Goodreads.