Light Aircraft IC Engine and Propellers EXAM NEWEST EXAM COMPLETE QUESTIONS AND CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |ALREADY GRADED A+||BRAND NEW VERSION!!

Light Aircraft IC Engine and Propellers EXAM NEWEST EXAM COMPLETE QUESTIONS AND CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |ALREADY GRADED A+||BRAND NEW VERSION!! What type of propulsion units are commonly used in light aircraft? - Answer- Reciprocating spark-ignition engines using Aviation Gasoline (AVGAS) driving propellers. are diesel engines widely used in light aircraft? - Answer- Despite lower SFC, diesel engines have not been widely used in light aircraft. What cycle do gasoline engines in light aircraft operate on? - Answer- Otto Four Stroke Cycle: induction, compression, expansion, and exhaust. Piston engine advantages - Answer- - low cost - simple construction - easy to maintain Piston engine disadvantages - Answer- - lack of power especially at altitude (hence supercharging on some models). - relatively low airspeed due to propeller limitations. - lower reliability compared to gas turbines. The four stroke cycle - Answer- invented by Nikolaus Otto, 1. intake - air-fuel mixture drawn in. 2. compression - air-fuel mixture compressed. 3. combustion - explosion forces piston down. 4. exhaust - piston pushes out burned gases. What are the ignition features of piston engines in aircraft? - Answer- Two engine drives magnetos supplying two independent spark plug systems. provision for carburettor anti-icing. What are the fuel system options for piston engines in aircraft? - Answer- Can be normally aspirated, fuel injection, or supercharged, using aviation-rated fuel. what cooling system for piston engines - Answer- generally air-cooling Reciprocating engine key parts (6) - Answer- -propeller shaft -exhaust manifold -cylinder bank -inlet manifold -air inlet -carburettor Reciprocating engine types (9) - Answer- -inline -inverted inline -rotary -horizontally opposed -H in-line -V in-line -Inverted V in-line -radial (single row) -radial (two rows) Carburettor key parts (5) - Answer- intake venturi jet float chamber air intake Fixed Pitch - Answer- a one-piece propeller with a single fixed blade angle. The pitch (blade angle) must be high enough to offer good cruising performance yet low enough to achieve acceptable take off and climb characteristics. Controllable Pitch - Answer- a propeller which allows the adjustment of blades to any desired angle during flight. Constant Speed - Answer- a propeller used with a governor, that automatically provides constant RPM by counteracting the forces acting on the propeller to change the blade angle within a pre-set range. Full-Feathering - Answer- a propeller which allows blades to be rotated to a high positive angle to stop rotation (windmilling) after an engine is shut down, thereby reducing drag and asymmetric control forces on twin-engine applications. Reversing - Answer- a propeller with blades that can be rotated to a position less than the normal positive low blade angle setting until a negative blade angle is obtained, producing a rearward thrust to slow down, stop or move the aircraft backward, typically fitted only to turbine installations. Beta Control - Answer- a propeller which allows the manual repositioning of the propeller blade angle beyond the normal low pitch stop. These are used most often in taxiing, where thrust is manually controlled by adjusting blade angle with the power lever. These types of propellers are installed exclusively on turbine engines. - Answer- Blade - Answer- one arm of a propeller from hub to tip. Hub - Answer- centre section of the propeller which carries the blades and is attached to the engine shaft. Spinner - Answer- a metal cover enclosing the propeller hub, which improves the appearance of the propeller and may also streamline airflow for engine cooling purposes. Blade tip - Answer- the part of the blade furthest from the hub. Blade shank - Answer- the section of the blade nearest the hub. Blade butt - Answer- the portion of a blade inside the hub used to retain the blade. Blade camber surface - Answer- the cambered or most-cambered side of a blade (visible from front of the aircraft). Blade face or thrust surface - Answer- the flat side of a blade (normally visible from the cockpit of the aircraft). Blade leading edge - Answer- the forward full "cutting" edge of the blade that leads in the direction of rotation. Blade trailing edge - Answer- the continuous edge of the blade that trails the leading edge in the direction of rotation. Governor - Answer- a device, generally mounted on and driven by the engine, which senses and controls engine speed (RPM) by hydraulically adjusting the blade angle of the propeller. Prop diameter - Answer- the diameter of the circle circumscribed by the blade tips. Blade station - Answer- one of the designated distances along the blade as measured from the centre of the hub. Blade thickness - Answer- the maximum thickness between the cambered surface and the face or thrust surface at a given blade station. Blade width - Answer- the measurement between the leading edge and the trailing edge at a given station.