Chapter 2 Sections a and B_Systems

Review Questions 1. What are techniques to prevent

severity of ear problems in flight?2. What is the decision altitude for

determining scuba diving wait times?

3. What is the max FAR BAL and hours before operating an aircraft?

4. What are the 5 hazardous attitudes as a pilot?

5. High performance aircraft require how much horsepower for classification as such?

6. What are the 3 P’s?7. What does PAVE stand for?

8. FARs are divided into __ & ___.9. Syllabi are based on the ___ ___

theory of learning.10. What are the 3 general

requirements for obtaining a student pilot certificate?

11. How long is a 3rd class medical cert valid for if you are 19 years old?

12. What are the 3 ways to organize aircraft?

13. How often you have to complete a flight review?

14. What does class SEL mean?15. Do you need a type rating to fly a

Cessna 172?

Answer SheetName: ___________________

1. __________________2. __________________3. __________________4. __________________5. __________________6. __________________7. __________________

8. __________________9. __________________10. __________________11. __________________12. __________________13. __________________14. __________________15. __________________

Airplane Systems

Chapter 2 Section AAirplanes

Airplanes•Five basic components• Wing• Fuselage• Empannage• Powerplant• Landing Gear

Fuselage• Includes cockpit, attachment points, cargo •Primary Function:• To accommodate the payload• Payload includes passengers, cargo, luggage, and other useful loads

Attachment Points

Open Truss• Clearly visible struts & wire-braced wings• Original aircraft design• Constructed of steel or aluminum tubing• Strength and rigidity is achieved by welding the tubing together• Forms a series of triangular shapes, called trusses.

•As technology progressed, aircraft designers began to enclose the truss members • Streamlined the airplane and improve performance

Semi- and Monocoque Fuselages

Stressed SkinMonocoque or Semi Monocoque

• Cloth or fabric initially covered the open truss design, then metals • Uses the “skin “to support almost all imposed loads• Strong, but cannot tolerate any dents or deformation• Limited in design, invented semi monocoque

Stressed SkinMonocoque or Semi Monocoque

• Needed a substructure to attach the “skin” to• The substructure:• Bulkheads and/or formers of various sizes and stringers,

• Reinforces the stressed skin by taking some of the bending stress from the fuselage

Which aircraft is semimonocoque in design?

Wing• Takes maximum advantage of lift to help the aircraft fly

• Described by wing placement Also described by number of wings• High, mid, low- wing aircraft Monoplane, Biplane

Ailerons & Flaps

Ailerons• Extend out from mid-point of each wing toward the tip • Move in opposite directions to create aerodynamic forces• This causes the airplane to turn

Flaps• Extend outward from the fuselage to the midpoint of each wing• Normally flush with the wing’s surface during cruising flight• When extended, move downward to increase lifting force for takeoffs & landings

Empennage

Vertical Stabilizer

Horizontal Stabilizer

Rudder• The rudder is attached to the back of the vertical stabilizer• Can be used to move the nose of the airplane left or right• Like a rudder is used to turn a ship• The foot pedals move the rudders via cables• Pressing the left rudder pedal

• Connecting cables move the rudder left• Causes the aircraft’s nose to move to the left

Elevator• The elevator is attached to the back of the horizontal stabilizer• You can use it to move the nose up and down• Directs the airplane to the desired altitude or height

Stabilator• One-Piece horizontal stabilizer called a stabilator. • Used in lieu of an elevator• Horizontal stablilizer and elevator combination• Pivots up and down on a central hinge point• Pull back on the control wheel, nose moves up• Push forward, the nose moves down• Uses an Anti Servo Tab• To provide you with a control “feel” like elevator• Need to prevent over controlling the stabilator

Trim Devices• Trim Tab• Usually located on the elevator• Tab lessens the resistance you feel on the flight controls• Due to the airflow over the associated control surface• Controlled by a wheel in the cockpit

Landing Gear: Wheels• Two main wheels plus one extra• The “extra” wheel determines the name

• Conventional or• Tricycle

• Conventional Landing Gear aka Tailwheel• Purpose is to add clearance between prop and ground on unimproved sfc

• Tricycle Gear have a Nosewheel• Steerable or• Castering

Castering vs Steerable Nosewheels

• Steerable nosewheel• Steer with rudder pedals or a wheel in the cockpit• Linked by cables or rods• Jet Blue pilots make centerline landing with malfunctioning nose wheel

http://www.metacafe.com/watch/3097362/nose_wheel/

• Castering nosewheel• A nosewheel of a tricycle undercarriage • Not directly steerable but is free to swivel• Combine rudder pedals and brakes to steer, differential braking• Are NOT linked to rudders by cables and rods

Struts• The common strut’s job is to absorb shock• Most common, Oleo Strut• Uses a piston enclosed in a cylinder with oil and compressed air• Absorbs bumps and jolts encountered during landing and taxi ops• Absorbs pressure rapidly and then slowly releases it

• Other types• Spring Steel• Bungee Cord

• Do not absorb shock• Transmit the shock to the aircraft at an acceptable rate• Reduces stress and tendency to bounce

Landing Gear: Fixed/Retractable• Fixed Gear• Always extended• Simple, low cost

• Retractable Gear• Stowed inside structure when not in use• Increases weight and cost• Limits use to high performance aircraft in general

• Review Question: What type of endorsement do you need to fly a retractable gear aircraft?

Brakes• Disc Brakes• Located on main wheels• Slows rotation of the wheel by the friction caused by pushing

brake pads against a brake disc with a set of calipers• Equal pressure should normally be applied to each brake at the same time• Press on top most portion rudder pedal to brake, the toe plate• Hydraulically actuated by a master cylinder, accumulator, connecting lines

• Differential Braking• Technique to steer more directly and pivot about a tight space• Using one pedal brake more or less than the other

• Hand operated parking brake• Holds pressure on both brakes to keep from rolling

Powerplant• Cowling

• Propeller• Translates the rotating force of the engine into a forward acting force• This force is called thrust• Most general aviation aircraft have a two-bladed propeller

• Engine• Has several jobs:

• Provides power to turn propeller• Has connected accessories which:

• Generate electrical power• Create a vacuum source for some instruments• Source of heat for pilot and passengers

• Firewall • Located between engine compartment and cockpit

• Protects occupants• Mounting point for the engine• Made of a reinforced metal

POH/AFM/PIM• Pilot’s Operating Handbook (POH)• Pertinent info about make and model• Was required to be aboard at all times, not necessarily functional

• Airplane Flight Manual (AFM)• After March 1st, 1979, aircraft were required by FAA to have an AFM• The AFM can be accessed by pilot during all flight operations• Most aircraft have a POH / AFM to satisfy the FAA requirement• Usually stays in the aircraft

• Pilot’s Information Manual (PIM)• Manufacturers publish a PIM

• Contains same info as POH/AFM except• Specific Weight & Balance and optional equipment included• Provides a useful study tool that doesn’t have to stay

in the aircraft

Airplane Systems

Chapter 2Section B

The Powerplant & Related Systems

Engines• Reciprocating• Most general aviation training airplanes use reciprocating engines• Less costly, still reliable

• Turbine• Most large passenger carrying planes use turbine engines• Large power output

• How an engine is made:• http://www.youtube.com/watch?v=vB0MIQVH9Mo&feature=related

Reciprocating

• Converts chemical energy into mechanical energy inside of cylinders

• What do we need to start a fire?• Fuel, oxygen and something to start it with...

• The process:• Fuel/air mixture flows into cylinder at desired ratio• Compressed by a piston• Ignited• Combusted • Creates energy• Gets converted into work• Transferred through a crankshaft• To the propeller• Props move• Forward thrust• You fly!

Main Components

4 Stroke Cycle

Induction Systems• Brings outside air into engine• Intake port with air filter and alternate source

• Mixes with fuel at specific ratio• Delivered to engine cylinders for combustion• You control the amount of fuel and air (*in a Fixed-Pitch Prop System)• Throttle

• Controls engine speed, displayed on Tachometer• Regulates AMOUNT of fuel and air into cylinders

• Mixture control• Controls RATIO of fuel and air into cylinders

• Tachometer• Engine speed displayed in RPM

Throttle and Mixture Controls

Carburetor• Air moves through induction system and to the carburetor• Passes through a Venturi on it’s way• Venturi increases velocity, decreases pressure• Goes into the carburetor via a float chamber• Vented for equal to atmospheric pressure in any flight condition• Kept at constant level due to float device• Discharge nozzle operated by differential pressure

• Nozzle distributes fuel and delivers it to chamber for combustion with air• Calibrated at sea level, but adjusted for density altitude starting with full rich• Altitude increases, air density decreases, so mixture must be adjusted

• The fuel density does not change, so we accommodate the air density• If not corrected, engine problems

• Roughness, spark plug fouling, rich cold mixture, incomplete combustion• Occurs during pretakeoff runup at high alt, in climb or high alt cruise• Monitor EGT to adjust mixture

Venturi EffectBernoulli’s Principle + Continuity Equation = Venturi Effect

Bernoulli’s Principle: An increase in the speed of the fluid occurs simultaneously with a decrease in pressure or a decrease in the fluid's potential energy.

Newton's 2nd law and Bernoulli’s Principle:

If a small volume of fluid is flowing horizontally from a region of high pressure to a region of low pressure, then there is more pressure behind than in front. This gives a net force on the volume, accelerating it along the streamline.

Float Type Carburetor

Carburetor Icing• Due to effect of fuel vaporization • Decreasing air pressure in Venturi

• Sharp temperature drop• Ice can form

• Most likely to occur when temperatures are: Below 21’C (70’F) and relative humidity above 80%

• However, can occur with high temps, low humidity, temps near 38’C (100’F), humidity low as 50%

• Likely to occur at reduced power, descent• First indications• Fixed pitch propeller

• Decrease in engine RPM, engine roughness• Apply Carb Heat and get decrease in RPM, then rise in RPM, ice melts

• Constant Speed propeller• Power changes seen in manifold pressure gauge

• Carburetor Heat• Eliminates ice by routing air across heat source before entering• Causes slight decrease in engine power, hot, less dense air, enriches mixture

Fuel Injection

Fuel Injection

• Four basic components:• Fuel pump, fuel control unit, fuel manifold valve, fuel discharge nozzles

• Engine driven fuel pump & Electric fuelpump/Aux fuel pump• You don’t have to worry about Carburetor Icing with a Fuel Injected Engine!• Lower fuel consumption, increased HP, lower temps, longer engine life• Discharge nozzles are located in each cylinder head• Inject fuel/air mixture directly into cylinder intake port, for combustion

Super & Turbo Chargers

• Superchargers and Turbo Chargers • Allow reciprocating engines to operate at high altitudes at lower air density• Compress the intake air further to produce increase in overall engine output• Both usually fuel injected

• Supercharger• Compresses incoming air using an engine driven pump• Power from engine required to drive pump, therefore a little power lost

• Turbocharger• More efficient, pressurizes air using exhaust gases• Supplies air for cabin pressurization

Ignition System

• Provides spark to ignite• Magnetos• Spark Plugs• Wires• Switch

Magnetos• A self contained, engine driven unit which supplies electrical current to spark plugs• Each mag operates independently to fire one of the two spark plugs in each cylinder• If one mag fails, other is unaffected, slight decrease in power, same for spark plugs• Redundant system• Each mag is connected via a ground wire• If this ground wire disconnects, the mag may still fire• This is why we do a “mag check” in our checklist

• Magnetos are controlled by the ignition switch• OFF, RIGHT, LEFT, BOTH, START• Check the right by selecting the left and look for RPM decrease

• Hazards• If battery and master switches OFF, engine can still fire if Ignition ON and prop moved• Turn the Mags, Master, Ignition all off and double check it!

Ignition Switch

Abnormal Combustion• Usually combustion is smooth buildup of temperature and pressure• Ensures max force to pistons at the right time for power

• Detonation• Uncontrolled, explosive ignition in the chamber• Can lead to failure of piston, cylinder or valves• Overheating, roughness, loss of power• Happens when you let the engine overheat, use a lower grade of fuel

• Fuel grades• Use recommended, you can go higher, not lower

• Preignition• Fuel air mixture ignited before it’s time to ignite• Caused by a hot spot in the cylinder, carbon or cracked spark plug

• Detonation and Preignition can occur together• Attempt to lower temperature by retarding throttle, enriching the fuel, lowering nose

Fuel System• Require fuel pump: Fuel-pump system• Requires potential energy from gravity: Gravity Feed System

Fuel Pump System

• Found in low wing airplanes• High performance airplanes• Has two pumps• One for when engine is running

(Engine-Driven Pump)• Other for when not running

(Electric Boost Pump)• Fuel Pressure Gauge• Helpful in ensuring constant ops• Turn on boost if pressure drops

• Hazard• Vapor Lock

• Tank fully dry• Air can enter fuel system

Gravity Feed System

• Found in high wing airplanes• Uses gravity for flow• Has a manual pump• Called Primer• Pumps fuel directly into intake

before starting engine• For use in cold weather

• Difficult for fuel to vaporize

Components of Fuel System• Fuel tanks• Located in wings• Vent the fuel

• Filler Caps• Small tube extending from wing

• Overflow drain• Drain on hot day (expansion)

• Fuel Quantity Gauges• Displayed in gallons, pounds• Left and Right Tank• Not always reliable – check

• Fuel Selector Valve• LEFT, RIGHT, BOTH, OFF

Fuel Drain Tool• Check during pre-flight• Ensures contaminants checked from a tool used to drain from tank• Water is heavier than fuel and other contaminants

• Sinks to the bottom, is clear, vs fuel color

Refueling Operations

Oil System• Lubricates moving parts in engine• Cools engine, reduces friction, removes some heat from cylinders• Provides seal between cylinder walls and pistons

Dry-Sump vs Wet Sump Systems• Dry Sump • Oil is contained in a separate tank and circulated by pumps

• Wet Sump• All of the oil in in one sump• Suitable for most reciprocating engines

Wet Sump System

Dry Sump System

Oil Gauges

Cooling System• High engine temps• Loss power, high oil consumption, engine damage

• Outside air enters through an inlet, baffles direct to hot parts, like cylinders• Less effective during• Takeoffs, go-arounds,

low airspeeds…• Open Cowl Flaps• Enrichen mixture • Reduce Rate of Climb• Increase AS• Decrease Power

• May be too effective during• High speed descents

Exhaust System• Vents burned gases overboard• Provides heat for cabin and defrost• Directs exhaust out below engine through:• Muffler

• Heat is transferred to incoming air via muffler and shroud• Then ducted to cockpit for cabin and defrost air

• Tailpipe

Propellers

• Provides the thrust to propel airplane• Central Hub, Two or more blades attached; 2 for general avation• Each blade is a rotating wing, produces thrust• Amount of thrust produced by each section dependent on:• Shape• Rotational speed • Position relative to oncoming air

• Greater power required? Greater prop blade area required.• However, limited by efficiency of size vs power produced• Blade tip can reach speed of sound and increase drag, efficiency decreases

• More props can be quieter

• How props are made:•http://www.youtube.com/watch?v=DvWKfu4ubik

Sections & Lift• The prop is twisted!• Sections are divided horizontally across the blade• Each section has it’s own shape, therefore different effect on lift• The twist allows for a nearly uniform thrust throughout the length• Each section has a different angle relative to plane of rotation• Blade angles or blade pitch

Fixed Pitch Propeller

• Blade Angle is permanently selected• Depends on primary function• Cannot be changed by pilot

• Power control is throttle• Power indicator is Tachometer• Is connected directly to engine crankshaft

Constant Speed (RPM) Propeller

• Also known as Variable Pitch Propeller or Controllable Pitch Propeller• You can adjust the blade to be efficient for various phases of flight• Converts a high % of power to thrust• Allows for wide range of RPM and AS combinations• Controlled by throttle directly• Controlled by Propeller control indirectly

• Changes pitch of propeller blades• Power output is measured in Manifold Pressure, gauge, psi• Blade angle is changed through pressure provided by oil, hydraulically

•Phases of flight for various prop angle and power settings• Takeoff

• Low blade angle and high RPM, max thrust• Cruising Flight

• Higher blade angle and lower RPM• Like using a low gear in your car, accelerating and then switching gears

Constant Speed Prop

Electrical System• Alternator• AC to DC• Bus Bar• Circuit Breakers

• Battery• Starts engine• Can provide emergency standby power

• Ammeter• Monitors electrical current in amperes • Two types

• One reflects current flowing to or from battery• Other shows displaced load on system

Master Switch

• Controls entire electrical system• Starter won’t operate unless master is on• Is split- rocker type to isolate alternator/battery if necessary

Circuit Breakers• Fuses which protect various components from overloads• Resetting circuit breakers reactivate circuit

• If overload exists, CB continues to pop• Electrical problem

• Low Voltage Warning Light • May signal electrical problem• See POH