One of the old, bold former flight engineers that ran my ATPL brush up ground school, reckons that V1, V2 etc were introduced after the comet crash in Rome, where the crew tried to rotate 10kts below "flying speed"?
Also, He reckons that the performance factors we use today (clearing obstacles by 35ft in the dry, 15ft in the wet, screen heights of 50ft, needing 115% of LDR for landing, etc etc), was all based on what a Boeing 707 needed to takeoff / land in southern California in the summer. Any comments?
TTR