>Perhaps the FAA believes that it is better to minimize change fatigue. Additionally you might want to avoid the association that specific pack supplies air to

>Perhaps the FAA believes that it is better to minimize change fatigue. Additionally you might want to avoid the association that specific pack supplies air to the cockpit, as it varies across generations. https://en.wikipedia.org/wiki/Kegworth_air_disaster https://en.wikipedia.org/wiki/Kegworth_air_disaster