In the early days of airmail flying, the mail pilots came to believe that their crash rate was unacceptable, even for people accustomed to danger. Finally, a group of them convinced the U.S. Air Mail Service that postal supervisors at the airports were ordering them aloft in bad storms and poor visibility. The solution? Not a new regulation spelling out what weather was safe and unsafe, but rather this simple order: if an outgoing pilot desired, his supervisor had to join him in the cockpit to fly a circuit around the airport before the pilot went off on his mail run. Quickly the supervisors’ tolerance for bad weather dropped.