R22 Basics Flashcards
How long is the R22?
259” from front of skid to rear tail rotor.
345” from front tip of rotor path plane to the rear of the tail rotor
How wide is the R22?
76” from skid to skid.
44” wide cockpit
How tall is the R22?
69” from ground to top of cockpit.
107 inches from top of rotor mast to ground.
What is the diameter of the main rotor?
25’ 2” (302”)
What is the diameter of the tail rotor?
42” (3’6”)
What is the engine/powerplant of the R22?
A Lycoming O-320 or O-360 Four-cylinder reciprocating engine.
Describe the four-cylinder engine.
The four cylinder engine is a horizontally-opposed, direct-drive air-cooled, carburetor equipped, normally aspirated piston engine, equipped with a starter, alternator, shielded ignition, two magnetos, muffler, oil cooler and induction air filter.
Fuel and air are mixed inside the cylinders, compressed, and then ignited – producing an explosive force and causing the pistons to move inward.
What does horizontally-opposed mean?
Pistons are connected from the cylinders to a crankshaft, with each cylinder positioned side-by-side, horizontally.
When they move inward and outward, they cause the crankshaft to rotate which turns the engine output shaft
(as well as the cam shaft, which opens and closes the two valves that let the air-fuel mixture in to the cylinder and exhaust gases out).
What does it mean that the engine is direct-drive?
It means there is direct power transfer to the lower and upper sheaves.
A vee-belt sheave is bolted directly to the engine output shaft. The vee-belts transmit power to the upper sheave which has an overrunning (sprag) clutch contained in its hub. The inner shaft of the clutch transmits power forward to the main rotor and aft to the tail rotor. Flexible couplings are located at the main gearbox input and each end of the long tail rotor drive shaft.
What does carbureted mean?
The piston engine is carburetor-equipped. The carburetor mixes air with the fuel that gets sent to the cylinder combustion chambers. Fuel arrives at the carburetor and sits in the float chamber, waiting to be used. To the side of the float chamber is the venturi which is where the air passes through on its way to the cylinder. As the air passes through the venturi, its velocity increases, which produces a decrease in pressure. Towards the bottom of the venturi is the fuel discharge nozzle, which draws fuel the fuel out of the float chamber, due to the drop in pressure, and mixes it with the air. Just beyond the venturi is the throttle valve, which controls how much of the fuel-air mixture is sent to the cylinders.
What does normally-aspirated mean?
This refers to an internal combustion engine in which oxygen intake depends solely on atmospheric pressure and does not rely on forced induction through a turbocharger or supercharger.
What is the horsepower of the engine (normal rating)?
145 BHP (derated) @ 2700 RPM
What is the maximum continuous rating in R22?
124 BHP at 2652 RPM (104% on tachometer)
What is the five-minute takeoff rating in the R22 Beta II?
131 BHP at 2652 RPM
What is the cooling system on the R22?
A direct-drive squirrel cage blower
