Why can aeroplanes climb with huge feet per minutes in the lower airspace, but when climbing at FL300, the....

Question

....... feet per minutes decline (so at FL100 you maybe climb with 3000 fpm, but at FL300 you just climb with 1500 fpm)?

Answer 1

Less airflow over the wings making lift

Less air into the engine to get combined with fuel and burned.

The result is a decrease in performance as the airplane climbs.

Answer 2

As you go up, the air is thinner, so you have less air that can be displaced through an engine to make the aircraft go higher and faster. It's why many airlines, especially American Airlines MD-80 pilots, are notorious for doing a 45-degree "straight up" climb right off the runway, because it's easier to get it up then than it would be further up.

Answer 3

The air is a lot thinner at 30,000 Ft that at 10,000 Ft so the wings develop less lift and the engine less thrust. Air temp. also has a lot to do with lift and trust.

Answer 4

Air density is lower at altitude.  less "air" = less lift

Answer 5

The answer is change in density. Lift and thrust (drag too) are dependent on density, the higher you go, the lesser the density and so comparitively lesser the influences of lift, thrust and drag.

Thats the reason why airplanes have an operational ceiling.