Helicopter Powerplants

Most common helicopters are either powered by a traditional piston engine, or by a light-weight turbine. In either case the powerplant is typically responsible for rotating some type of power shaft that is used to turn a transmission which normally then turns the main rotor blades, the tail rotors, and various other system components such as electrical generators.

Piston Engines

Most student helicopter pilots will begin their training in a piston powered helicopter. Both Schweizer 300's and Robinson R22's are popular piston powered helicopters used in this role. Although piston engines actually have less reliability, weigh more, and contain more moving parts, they are generally cheaper to maintain and replace than their turbine counterparts. Because piston powerplants generate a fairly limited amount of power, most training helicopters must be operated within a relatively narrow set of performance limitations.

Piston engines feed an air-fuel mix into the heads of several cylinders which are constantly firing or exhausting based on the repeated opening/closing of a set of valves. Reciprocating piston engines are very common in the automotive world, and there is a great deal of reference information available on the internet, should you want to learn more about them.

Turbine Motors

After completing their basic training requirements, many student pilots will continue on to receive their ratings in various turbine powered helicopters. Turbine motors are typically lighter, simpler in design, and contain less moving parts than their piston counterparts. However, they are more expensive to purchase and maintain due to their sophistication and small tolerances for improper configuration.

Simple turbine motors compress incoming air, mix it with fuel, ignite that mixture, and using the rapidly expanding exhaust gases to spin power producing turbines. In most helicopters the exhaust pipes simply release the remaining hot gases from this process, but do not contribute to the forward motion of the helicopter. So while these turbine engines, are in fact jet engines, they should not be confused with the turbo-fan type jet engines used on passenger or fighter jets. If you would like to learn more about turbine powerplants, there is a wealth of information available on the internet.