Originally Posted by
ConnieLover
tonytales --
I remember being told long ago that DC-4s were not pressurized. Is that true? If not, how could they have had what Wikipedia claims is a service ceiling of 22,300 feet without everyone on board needing oxygen? And -- if DC-4s were, indeed, pressurized, how did their aft toilet flush without depressurizing the airplane?
"Service ceiling" means the maximum altitude at which the aircraft can maintain a 50 foot per minute rate of climb with full available power.
Has nothing to do with the ability of crew/pax to survive. Other regulations cover availability of oxygen above a certain altitude.
C2j