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Dual ignition for a piston engine provides a factor of reliability and:
  • A
    improves combustion efficiency.
  • B
    provides more voltage.
  • C
    improves starting.
  • D
    saves wear caused by using one magneto constantly.
The major components of a piston engine are:
  • Cylinder and cylinder’s head – consisting of a gas-tight barrel and a head assembled together. Usually, the barrel is made of steel and is fitted with fins that will help to disperse heat, whereas the head is made of alloy.
  • Spark plugs – there’re usually two plugs per cylinder for redundancy and for more uniform combustion on either side of the cylinder to improve combustion efficiency. The additional spark plug in each cylinder helps to accelerate the combustion process, because the flame front spreads out from both plugs simultaneously. This causes a quicker rise to peak cylinder pressure and, thus, a noticeable increase in power. This is why engine RPM drops slightly when each magneto is switched off during the pre-flight magneto check.
  • Pistons – made of aluminum alloy and consisting of the head (top part) and the ‘skirt’ (lower part. It is carefully designed to improve its efficiency and safe operation – it has compression rings that prevent the gases from escaping toward the lower part of the cylinder and oil control rings to ensure oil is spread evenly all over the inner surface of the cylinder.
  • Connecting rod – stiff ‘H’ shaped important element that connects the piston to the crankshaft by means of a hinged axle.
  • Crankshaft - a linear assembly consisting of rotary components that will convert the piston’s linear movement into a rotary movement transmitted to the shaft. Among others, you could find the following components in a crankshaft: the crank web, the crankpin, the journal, and the balance weights.
  • Camshaft - a shaft containing several attached disks of irregular shape that operate the intake and exhaust valves.
  • Crankcase – it is the structural ‘box’ within which the engine is located. It serves as a mounting point for the cylinders, the accessory gearbox, the engine. It is carefully designed to lubricate itself and all the related components (bearings, pistons, etc.) via its numerous internal passages. Usually, it is made of a strong alloy such as magnesium.

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