Machol discusses it in this address he gave at a 1992 sciences conference; it's on page 10. https://icus.org/wp-content/uploads/2017/05/Machol-Robert-E.-Air-Tr

Machol discusses it in this address he gave at a 1992 sciences conference; it's on page 10. https://icus.org/wp-content/uploads/2017/05/Machol-Robert-E.-Air-Transport.pdf https://icus.org/wp-content/uploads/2017/05/Machol-Robert-E.... He says that the calculations they did at the FAA suggested that for each infant saved by requiring a separate ticket, six would have been killed in car crashes. (That's not my original source; it's just the first thing I found.)