Stage 3 Lesson 12

Aircraft systems

What is the purpose of Primary flight control?

• change the airflow and pressure distribution over and around the airfoil. 

• These changes affect the lift and drag produced by the airfoil/ control surface combination, and allow a pilot to control the aircraft about its three axes of rotation.

What are the Primary Controls?

Aileron, Elevator/Stabilator, and Rudder

Ailerons Control movement about _____, Axes of rotation is about the _____, and the type of stability is along the _____.

Roll, Longitudinal, and Lateral

Elevator/Stabilator Control movement about _____, Axes of rotation is about the _____, and the type of stability is along the _____.

Pitch, Lateral, and Longitudinal

Rudder Control movement about _____, Axes of rotation is about the _____, and the type of stability is along the _____.

Yaw, Vertical, and Directional

Ailerons control roll about…

Longitudinal Axis.

What is Adverse yaw?

• condition of flight in which the nose of an airplane tends to yaw toward the outside of the turn.

  • This is caused by the higher induced drag on the outside wing, which is also producing more lift

  • Induced drag is a by-product of the lift associated with the outside wing

  • Increased drag pulls the nose opposite the direction of the roll.

  • Most noticeable: Low airspeeds, High angle of attack, and Large aileron deflections

What are the different type of systems used to reduce adverse yaw?

Differential Ailerons

Frise-Type Ailerons (Our planes)

Coupled Ailerons/Rudder System

Flaperons

What are Differential Ailerson?

one aileron is raised a greater distance than the other, this produces more increase in drag on the descending wing

What are Frise-Type Ailerons?

projects leading edge of the aileron into the airflow and creates drag

What are Coupled Aileron/Rudder Sytems?

Rudder-aileron interconnect springs, which helps correct for aileron drag by automatically deflecting the rudder at the same time the ailerons are defected

What are Flaperons?

combined both aspects of flaps and aileron

What is an Elevator?

controls pitch about the lateral axis.

• Back pressure → Elevator up → Tail down → Nose up.

strength of the pitching moment is determined by the distance between the CG and the horizontal tail surface,

What is a Stabilator?

essentially a one-piece horizontal stabilizer, has a swivel point and whole horizontal piece moves

What is a Rudder?

Controls movement about the vertical axis.

• When the rudder is deflected into the airflow, a horizontal force is exerted in the opposite direction

What is a T-Tail?

Elevator mounted on top of vertical stabilizer.

What is a V-Tail?

Ruddervators combine elevator and rudder functions.

• A Little faster but loose  controllability 

What are the purpose of Secondary Flight controls?

• Improve aircraft performance and handling.

• Used to increase lift, increase drag, or reduce pilot workloads (and pressures you need to use)

What are the types of Secondary Flaps?

• Flaps – Increase lift and drag.

• Leading Edge Devices – Delay stall and increase lift.

• Spoilers – Reduce lift and increase drag.

• Trim Systems – Reduce pilot control pressures.

• Servo Tabs

• Anti Servo tabs

What are flaps? Draw cordline

•  most common high-lift devices used on aircraft. 

  • Mounted on the trailing edge of the wing.

  • Increase wing camber, Maximum lift, delays stall and improved low-speed performance.  

  • Increase cordline and allows use to have an approach at lower angle of attack 

What are the types of Flaps?

• Plain Flaps: pivot down from the wing's trailing edge to increase camber and lift.

• Split Flaps: hinge from the underside of the wing, dropping down like a hidden panel to boost lift.

• Slotted Flaps: have gaps that let high-pressure air flow from below the wing to the top, delaying stall and allowing more lift with less drag.

• Fowler Flaps: slide back before hinging down, increasing both camber and wing area. 

• Slotted Fowler Flaps (our planes): Combining the best of both worlds, Slotted Fowler flaps slide back, hinge down, and create slots for smooth airflow.

What are leading Edge Devices?

High-lift devices also can be applied to the leading edge of the airfoil

What are the most Common types of Leading Edge devices?

• Fixed slotted: permanent opening through the leading edge of the wing.

• movable slats: a movable slot.

• leading edge flaps (“droop flaps): a hinged section at the front of the wing that droops downward when deployed.

• Cuffs: a permanent modification to the leading edge shape

What are spoilers?

high drag devices that are deployed from the wings to spoil the smooth airflow, reducing lift and increasing drag

• Destroy lift and increase drag.

What are Trim systems used for?

Used to relieve the pilot of the need to maintain constant pressure on the flight controls

• Improve pilot comfort and workload management.

What are some Trim Systems?

• Trim Tabs: attached to the trailing edge of an elevator, and it's operated by moving a small control wheel in the cockpit.

• Balance Tabs: looks like trim tabs, but they have one major difference: balance tabs are attached to the control surface linkage, so when the control surface is moved in one direction, the balance tab moves in the opposite direction.

• Servo Tabs: helps to move the entire flight control surface in the direction that the pilot wishes it to go.

• Antiservo Tabs: similar to balance tabs, but they move in the opposite direction. For example, when your elevator or stabilator moves up, the antiservo tab moves in the same direction.

• Ground adjustable Tab: only adjustable on the ground by an A and P or on your own plane 

What is the purpose of the powerplant?

Produces thrust to propel an aircraft forward.

How do Reciprocating engines and turboprop engines vs turbojet and turbofan engines produce thrust?

• Reciprocating engines and turboprop engines work in combination with a propeller to produce thrust

• Turbojet and turbofan engines produce thrust by increasing the velocity of air flowing through the engine

What kind of engines do we have?

• Our aircraft has a Lycoming IO-360-L2A

  • 180

  • Static RPM check

    • Breaks up to full power we want to see 2300-2400 (short field takeoffs)

How do Reciprocating Engines work?

• The name is derived from the back-and-forth, or reciprocating, movement of the pistons that produces the mechanical energy necessary to accomplish work.

• operate on the basic principle of converting chemical energy (fuel) into mechanical energy.

What are the two types of Reciprocating engines?

spark ignition and the compression ignition.

How do Spark Ignition engines work?

engines use a spark plug to ignite a pre-mixed fuel-air mixture.

How do Compression ignition engines work?

engine first compresses the air in the cylinder, raising its temperature to a degree necessary for automatic ignition when fuel is injected into the cylinder. (Diesel engines and jet engines)

What are some other ways to classify engines?

1. Cylinder arrangement: radial, In-line, v-type, or opposed

2. Operating cycle: two or four

3. Method of cooling: liquid or air

What are the four strokes of an engine?

• Intake = Suck

• Compression = Squeeze

• Power/Combustion = Bang

• Exhaust = Blow

What are the parts of a turbine engine?

an air inlet, compressor, combustion chambers, a turbine section, and exhaust.

How does a Turbine Engines work?

• Thrust is produced by increasing the velocity of the air flowing through the engine.

  • Basically 4 strokes in 1 line

• characterized by smooth operation and a high power-to-weight ratio, and they use readily available jet fuel.

What is a propeller?

• a rotating airfoil, subject to induced drag, stalls, and other aerodynamic principles that apply to any airfoil. 

  • provides the necessary thrust to pull, or in some cases push, the aircraft through the air. 

Why are propellers twisted?

The greatest angle of incidence, or the highest pitch, is at the hub while the smallest angle of incidence or smallest pitch is at the tip.

• The reason for the twist is to produce uniform lift from the hub to the tip.

What is a fixed Pitch Propeller? what are the two types?

• fixed blade angles

  • The pitch of this propeller is set by the manufacturer and cannot be changed. 

• There are two types of fixed-pitch propellers: climb and cruise. 

What is a climb prop for?

Has a lower pitch, therefore less drag. Less drag results in higher rpm and more horsepower capability, which increases performance during takeoffs and climbs but decreases performance during cruising flight.

What is a cruise prop for?

has a higher pitch, therefore more drag. More drag results in lower rpm and less horsepower capability, which decreases performance during takeoffs and climbs but increases efficiency during cruising flight.

What is a constant speed propeller

Propeller whose pitch is automatically varied in flight by a governor to maintain a constant rpm in spite of varying air loads

• The propeller's blade pitch is changed hydraulically, using engine oil and the blue prop control in the cockpit

What is a controllable pitch propeller?

 able to be adjusted for different conditions of flight allowing for most efficient use

• Taking off: High RPM, Low blade angle, max power for takeoff

• Cruise Flight: Lower RPM, increased blade angle, More fuel efficient 

  • Pushing more air with less fuel

What are landing gear systems for? What are the two types of wheel position and there names? What are the three types of landing gears?

the principal support of the airplane when parked, taxiing, taking off, or landing

• Wheeled landing gear consists of three wheels—two main wheels and a third wheel positioned either at the front or rear of the airplane. 

  • Landing gear with a rear mounted wheel is called conventional landing gear.

    • Sometimes referred to as tailwheel airplanes

  • When the third wheel is located on the nose, it is called a nosewheel, and the design is referred to as a tricycle gear

• The most common type of landing gear consists of wheels, but airplanes can also be equipped with floats for water operations or skis for landing on snow.

The fuel system is designed to provide an uninterrupted…..

flow of clean fuel from the fuel tanks to the engine. The fuel must be available to the engine under all conditions of engine power, altitude, attitude, and during all approved flight maneuvers. 

What are the two common classifications apply to fuel systems?

gravity-feed and fuel-pump systems

How does Gravity-feed system work?

• utilizes the force of gravity to transfer the fuel from the tanks to the engine. 

  • Fuel is above the engine

How does Fuel-pump systems work?

• have two fuel pumps: Main Pump and Auxiliary pump

  • The main pump system is engine driven with an electrically- driven auxiliary pump provided for use in engine starting and in the event the engine pump fails. 

  • The auxiliary pump, also known as a boost pump, provides added reliability to the fuel system. The electrically-driven auxiliary pump is controlled by a switch in the flight deck.

What are the types of fuel?

• Fuel grades 100LL (blue) / AVGAS 100 (green)

  • 80 AVGAS (RED)/ Jet A (Yellow/straw) GAMEE (yellow)

What are the fuel tanks on our 172s/r models?

56 gallons total (28 gallons each tank)

• 53 gallons usable

What is the purpose of Oil?

• Lubrication of the engine’s moving parts

• Cooling of the engine by reducing friction

• Removing heat from the cylinders

• Providing a seal between the cylinder walls and pistons

• Carrying away contaminants

What are the two types of oil systems for a reciprocating engines?

• wet-sump system, the oil is located in a sump that is an integral part of the engine. 

• dry-sump system, the oil is contained in a separate tank and circulated through the engine by pumps. 

What kind of oil system does our plane have?

• Full pressure, Wet Sump-type lubrication system

• Oil Capacity 8 Quarts Indicated (9 Quarts if oil filter is installed)

  • Engine should not be operated on less the five (5) quarts of oil.

    • School Minimum is 6 Quarts

• Oil Is Pumped by an Engine Driven Pump

• Oil Grades & Type:

• Summer: SAE 15w-50 ashless dispersant

• Winter: SAE 15w-40 ashless dispersant

What are hydraulic systems?

Uses pressurized fluid to transmit force and move or operate mechanical components.

What are the basic Hydraulic system parts?

•  consists of a reservoir, pump (either hand, electric, or engine-driven), a filter to keep the fluid clean, a selector valve to control the direction of flow, a relief valve to relieve excess pressure, and an actuator.

What are the Hydraulic system on a 172?

The brakes

• Two master cylinders (each main wheel can be slowed separately)

What is the Electrical System in our 172?

• 28 volt - Direct Current system

• Belt-driven 60 Amp Alternator

• 24 volt, 14 Amp Hour Battery

What are Avionics and what are they used for?

Two terms: aviation and electronics. 

• It is the electronic systems used in aircraft that often include flight control systems, engine controls, flight recorders, communications, navigation, threat detection, weather radar, electro-optic (EO/IR) systems, fuel systems, and performance monitors.

What are the instruments in the Pitot-static instruments?

• utilizes the static air pressure and the dynamic pressure due to the motion of the aircraft through the air. 

• These combined pressures are utilized for the operation of the airspeed indicator (ASI), altimeter, and vertical speed indicator (VSI).

What are some instruments other than the pitot-static flight instruments we use?

• Attitude indicator shows the aircraft's pitch and bank using a miniature aircraft against a horizon bar, simulating the real attitude relative to the horizon.

• Heading indicator is a mechanical instrument that provides stable heading information

• The inclinometer is used to depict yaw, which is to the side-to-side movement of the aircraft's nose

• Turn-and-slip indicator: Yaw

• Turn Coordinator: Yaw and Roll

• Magnetic Compass

Explain the Environmental control system.

• control systems regulate cabin temperature, ventilation, pressurization, and airflow for occupant comfort and safety.

  • commonly provide heating, cooling, cabin pressurization, air circulation, and defogging functions.

• Environmental system malfunctions can lead to hypoxia, smoke hazards, carbon monoxide exposure, or passenger discomfort.

• We have 

  • Air Vents

  • Cabin Air

  • Cabin Heat

What is the difference between Deice and Anti-icing?

• Deice: equipment is designed to remove ice once it has formed

• Anti-icing: equipment is designed to prevent the formation of ice

What are some types of Deicing and anti-icing Equipment?

• Deicing boots: Inflatable boots consist of a rubber sheet bonded to the leading edge of the airfoil

• Thermal anti-ice: Use bleed air or heating pads to heat leading edges of wings, stabs and props

• Weeping-wing:  An antifreeze solution is pumped to the leading edge and weeps out through small holes to prevent and remove ice.

• Windscreen Anti-Ice: flow of alcohol to the windscreen or heating strips

• Propeller Anti-Ice: alcohol or electrically heated elements

• We have Pitot Heat and Windscreen defrost 

  • The 172 is not certified for flight in known icing conditions

What is Automation?

generally comprised of an integrated advanced avionics system consisting of a primary flight display (PFD), a multi function flight display (MFD)

What Instruments are shown on a PFD?

capable of displaying “6 pack”

What does an MFD show?

capable of displaying moving maps that mirror sectional charts.

How does Auto Pilot work?

• works on servos

  • 2 axes 

  • 3 axes