KLM Fokker 70 with reverse thrust applied. The two surfaces behind the engine can be seen in the deployed position, diverting the engine exhaust gases forward

Reverse thrust is the temporary diversion of a jet engine's output so that the exhaust gases are blown forwards rather than backwards. The resulting thrust force acts against the forward travel of the aircraft. Reverse thrust is used by many jet aircraft to help slow down just after touch-down, thus reducing wear on the brakes and enabling the aircraft to use shorter runways. It is also available on many propeller-driven aircraft through changing the pitch of the propeller blades to a negative angle, thereby directing air flow into the direction of travel. Image File history File links Download high resolution version (1000x706, 127 KB) Reverse thrust on a Fokker 70 of KLM at Bristol International Airport, Bristol, England. ... Image File history File links Download high resolution version (1000x706, 127 KB) Reverse thrust on a Fokker 70 of KLM at Bristol International Airport, Bristol, England. ... A Pratt and Whitney turbofan engine for the F-15 Eagle is tested at Robins Air Force Base, Georgia, USA. The tunnel behind the engine muffles noise and allows exhaust to escape. ... Jet aircraft with condensation trail Jet aircraft are aircraft with jet engines. ... This article needs to be cleaned up to conform to a higher standard of quality. ...

Regulations dictate, however, that a plane must be able to land on a runway without the use of reverse thrust in order to be certified to land there.

The application of reverse thrust can be identified by a sudden increase in the volume and pitch of the engines' sound just after touch-down. The reversers are usually clearly visible at the rear of the engines during use.

Frequently landings will use "idle reverse thrust" in which the engines do not actually spool up, but the reversers are activated. This use of the engines saves fuel, aids in noise abatement and improves engine life.

There are several different ways of reversing the thrust of a turbofan. The illustration shows a Target Reverser, where all of the efflux is reversed. Some high bypass ratio engines, use blocker doors in the bypass duct to redirect (just) the bypass air through a Cascade Reverser. CFM56-3 turbofan, lower half, side view. ... Typical bypass duct, in a high bypass ratio turbofan A bypass duct is an annular passage that allows some of a turbofans airflow to bypass the engine core, or gas generator. ...

External links

• Reducing Landing Distance