Fisher also conducted a program designed to allow aircraft to descend rapidly.
It involved reversing all four propellers simultaneously in flight.
On a Douglas C-54 Skymaster transport, the extremely high sink rates of up to 15,000 feet per minute in four seconds after reversal, produced a safe method of rapid descent for airliners.
The flight would start at 15,000 ft.,
three miles from the airfield before push over, landing and coming to a full stop in one minute and 50 seconds.
Fisher wrote that forward airspeed was well within normal parameters (200 mph (320 km/h)), with no decrease in controllability.

Fisher conducted nearly 200 of these high rate/low speed descents and demonstrated the technique for Generals"Hap" Arnold and Dwight Eisenhower in 1948.
For the latest pressurized airliners and combat aircraft that operated at high altitudes, this was an effective method of safely dumping altitude in the event of an emergency, and was adopted worldwide as a safe procedure.
Fisher was also instrumental in developing the use of reversing pitch to rapidly slow an aircraft, which allowed them to land safely on shorter runways, and, in general, greatly reduce the incidence of runway overruns.

Later, flying a U.S. Navy Grumman F8F Bearcat fighter, Fisher developed a way to fly "zero-g", vertical dives.
From 20,000 ft, the F8F would be nosed down into a vertical dive, while he simultaneously reversed the propeller pitch.
This technique allowed a controlled vertical dive at rates of descent that varied between 30,000 and 37,000 fpm.
Fisher also conducted a program designed to allow aircraft to descend rapidly. It involved reversing all four propellers simultaneously in flight. On a Douglas C-54 Skymaster transport, the extremely high sink rates of up to 15,000 feet per minute in four seconds after reversal, produced a safe method of rapid descent for airliners. The flight would start at 15,000 ft., three miles from the airfield before push over, landing and coming to a full stop in one minute and 50 seconds. Fisher wrote that forward airspeed was well within normal parameters (200 mph (320 km/h)), with no decrease in controllability.
Fisher conducted nearly 200 of these high rate/low speed descents and demonstrated the technique for Generals"Hap" Arnold and Dwight Eisenhower in 1948. For the latest pressurized airliners and combat aircraft that operated at high altitudes, this was an effective method of safely dumping altitude in the event of an emergency, and was adopted worldwide as a safe procedure. Fisher was also instrumental in developing the use of reversing pitch to rapidly slow an aircraft, which allowed them to land safely on shorter runways, and, in general, greatly reduce the incidence of runway overruns.
Later, flying a U.S. Navy Grumman F8F Bearcat fighter, Fisher developed a way to fly "zero-g", vertical dives. From 20,000 ft, the F8F would be nosed down into a vertical dive, while he simultaneously reversed the propeller pitch. This technique allowed a controlled vertical dive at rates of descent that varied between 30,000 and 37,000 fpm.
Herbert O. Fisher