engine-world

Ⅱ. Engine type and method for aircraft "Braking"　　　　　　

The method differs depending on the type of engine.
Turboprop Engine, Piston Engine
These can generate the braking force by setting the
propeller pitch to zero or reverse.
Turbofan Engine
The fan cannot change the pitch. Therefore, the device (thrust reverser) for deflecting fan air
diagonally forward is attached to the engine nacelle of the aircraft.
For large aircrafts,cascade type,pivot and door typeare used.
Although thebucket typeis used for the business machine, installation is an option, and
there are also aircraft that are not installed.
Turboshaft Engine
In the case of a helicopter, there is no such device because vertical landing is possible.
IIa.The other important roles of Engine for aircraft
Besides "THRUST" and "BRAKING", there are other important roles as follows.

①"Electric Power Supply"
The power necessary for control, lighting, etc. is supplied from the generator attached to the  engine gearbox.


② "Pressurized Air Supply"
The compressed air required for pressurization, air conditioning and anti-icing is supplied  from the bleed valve attached to the compressor of the engine.


③ "Hydraulic Pressure Supply"
The hydraulic pressure necessary for landing gear and steering gear is supplied from a  hydraulic pump attached to the engine gearbox.

In addition, while the engine is stopped, APU (Auxiliary Power Unit = Turboshaft Engine) or  ground support equipments.