Mt. Everest peak = 29029 feet above sea level. I think in WWII, in the CBI theatre, the Air Force used to fly the Hump (fly over the Himalayas) to resupply operations in China.
The aircraft most used for “The Hump” missions were the
C-46(Commando), C-47 (military DC-3), and C-87/C-109 (cargo versions of B-24 Liberator). The C-109 tanker version was used to transport the large quantity of fuel needed for the 1944 B-29 missions launched from the forward bases in China.
The route through “The Hump” went through the mountain passes, not over Everest.
From Wikipedia:
“Flying over the Hump proved to be an extremely hazardous undertaking for Allied flight crews. The air route wound its way into the high mountains and deep gorges between north Burma and west China, where violent turbulence, 125 to 200 mph (320 km/h) winds,[23][105] icing, and inclement weather conditions were a regular occurrence. Lack of suitable navigational equipment, radio beacons, and inadequate numbers of trained personnel (there were never enough navigators for all the groups) continually affected airlift operations.”
https://en.wikipedia.org/wiki/The_Hump