Moreover this doc makes it more apparent how much he waxes without real references: https://ntrs.nasa.gov/api/citations/20090007797/downloads/20090007797.pdf ht

Moreover this doc makes it more apparent how much he waxes without real references: https://ntrs.nasa.gov/api/citations/20090007797/downloads/20090007797.pdf https://ntrs.nasa.gov/api/citations/20090007797/downloads/20... > Routine calculations were made using slide rules. More complex calculations, such as stress analysis, required Friden mechanical calculators. Fascinating read. No the SR-71 didn't appear out of thin air in a sprint of intensity unheard of on earth to date. Turns out after the U-2 taught us so much we said let's make a higher, faster U-3 and then spent a decade on that concept in a series of designs and tests. I really wish that this kind of cherry-picked mythos building fact wasn't what made half of what built the perception of good engineering to most of my present and future colleagues.