Engine
The Engine in this helicopter is a Rolls Royce M250 C-30 gas turbine. It is capable of producing 650 shaft horse power and is smaller then and weighs less then a Chevy 350. That's because of the extensive use of exotic materials such as magnesium, titanium and stainless steel in it's construction. These exotic alloys have to be able to withstand extreme pressure, heat and high RPM's while providing reliable and consistent power throughout it's expected life cycle. A turbine engine that breaks down before it is expected to can have serious consequences placing both the pilot and crew aboard the helicopter at risk. There is no pulling over to the side of the road mid flight. Rolls Royce engines have proven themselves to be highly reliable with less need for maintenance then a comparable piston driven engine. It is these features that have allowed turbine engines to become the preferred engine for use in all aviation applications. High power to weight ratio, reliability and ease of maintenance greatly overcomes the disadvantage of high fuel consumption and price.
In this application, the engine turns both the main rotor drive shaft and the tail rotor drive shaft. By taking energy created from the thermal expansion of burning of fuel, axial movement across the turbine section is created. Another way to look at it is, the preceding burning of fuel and air hits the gas turbine and spins them to high rpm's. As the gas moves across multiple turbine disks, the energy of the expanding gasses is transferred to the rotating disks, which are packed full of turbine blades, and much like blowing air across a pinwheel, the motion of expanding gasses across a turbine disk causes it to spin. This spinning action is then turned into torque through the drive shaft and powers both the compressor, which in turn feeds the engine more air, and also the main and tail rotor drive shafts. To learn more, visit http://www.howstuffworks.com/turbine.htm.