Aerodynamics – What Makes Airplanes FlyAerodynamics – What Makes Airplanes FlyDoylestown Pilots AssociationDoylestown Pilots Association
Boy Scouts Aviation Day 10/13/2012Boy Scouts Aviation Day 10/13/2012
Maj William J. Doyle, Jr. Civil Air Patrol, New Jersey Wing, Assistant StanEval Officer
Check Pilot / Instructor-PilotCFI A&I, AGI, IGI, CFAI, FAAST Rep
Aerodynamics Lesson PlanAerodynamics Lesson Plan
• What is an Airplane and What Makes It FlyWhat is an Airplane and What Makes It Fly
• The AirplaneThe Airplane
• Flight ControlsFlight Controls
• Axes of Rotation Axes of Rotation
• Forces Acting on the Airplane in FlightForces Acting on the Airplane in Flight
• Dynamics of the Airplane in FlightDynamics of the Airplane in Flight
• Ground EffectGround Effect
• How Airplanes TurnHow Airplanes Turn
• Torque (Left-Turning Tendency)Torque (Left-Turning Tendency)
• Airplane StabilityAirplane Stability
• Stalls and SpinsStalls and Spins
How Do the Flight Controls Work?How Do the Flight Controls Work?
• Push the stick (or yoke) forward and the houses get bigger.• Pull the stick (or yoke) back and the houses get smaller.• Hold the stick (or yoke) back too long and the houses get really small
then they get bigger again. (You just did a loop.)
Parts of An AirplaneParts of An Airplane
Airplane ComponentsAirplane Components
Airplane Components - FuselageAirplane Components - Fuselage
Open truss clearly visible struts and wire braces
Stressed skins monocoque
skin supports all loads semi-monocoque
sub-structure riveted to skin to maintain shape and increase strength
Airplane Stressed-Skin TypesAirplane Stressed-Skin Types
Airplane Truss-Type Fuselage StructureAirplane Truss-Type Fuselage Structure
Airplane Components - WingsAirplane Components - Wings
Monoplane single set of wings
Biplane two sets of wings
Ailerons move in opposite directions for turns controls roll (or bank) controlled by yoke or stick
right pressure turns right left pressure turns left
Flaps extend downward to increase lifting force for landings and
sometimes takeoffs controlled by flap handle or switch
pre-selected positions or variable positions
Airplane Wings: Monoplane vs. BiplaneAirplane Wings: Monoplane vs. Biplane
Airplane Wing ComponentsAirplane Wing Components
Airplane Components - EmpennageAirplane Components - Empennage
Vertical Stabilizer and Horizontal Stabilizer help steady airplane for straight flight
Rudder controls yaw controlled by floor pedals
right pressure moves nose to right left pressure moves nose to left
Elevator (stabilator on Cherokee) controls pitch controlled by yoke or stick
forward pressure lowers nose back pressure raises nose
Trim Tab helps hold pitch attitude controlled by trim wheel
move wheel forward for nose down trim move wheel back for nose up trim
Airplane EmpennageAirplane Empennage
Airplane Components - Landing GearAirplane Components - Landing Gear
Gear Types Fixed Gear Retractable Gear Tricycle Gear Conventional Gear (tail dragger)
Landing Gear Struts Spring steel struts bungee cord struts oleo struts shock disks
Brakes Disc brakes Differential braking
Airplane Landing GearAirplane Landing Gear
Airplane Components - PowerplantAirplane Components - Powerplant
Engine provides power to turn propeller distinguishes airplane from glider
Firewall separates cockpit from engine mounting point for engine
Propeller translates engine rotational force into forward-acting
force called thrust
Airplane PowerplantAirplane Powerplant
Wing PlanformsWing Planforms
Aspect Ratio = Wing Span ÷ Average Chord
What Makes an Airplane Fly?What Makes an Airplane Fly?
• For an airplane to takeoff, thrust must overcome drag and lift must overcome gravity (sometimes called weight)
• So is there relevancy here to what you study in school?– Applicable Subject in School = Science– High School Course = Physics (study the chapter on Bernoulli’s Law)
What Makes an Airplane Fly?What Makes an Airplane Fly?
• The laws of physics apply to everything.• They apply to F-16 fighters and to the USAF Thunderbirds.
What Makes an Airplane Fly?What Makes an Airplane Fly?
• The laws of physics apply to everything.
• They apply to ultra lights.
What Makes an Airplane Fly?What Makes an Airplane Fly?
• The laws of physics apply to everything.
• They even applied to the Wright Brothers in the Wright Flyer at Kitty Hawk, NC.
Four Forces of FlightFour Forces of Flight
VectorVector
VectorVector
Four Forces of FlightFour Forces of Flight
Lift upward force from airflow over and under wing
Weight downward force of gravity
Thrust forward force propelling airplane through air
Drag rearward force retarding force limiting speed
Four Forces of FlightFour Forces of Flight
Newton’s Laws of Force and MotionNewton’s Laws of Force and Motion
Newton’s First Law A body at rest tends to remain at rest, and a body in
motion tends to remain moving at the same speed and in the same direction.
Newton’s Second Law When a body is acted upon by a constant force, its
resulting acceleration is inversely proportional to the mass of the body and is directly proportional to the applied force.
Newton’s Third Law For every action there is an equal and opposite reaction.
Bernoulli’s PrincipleBernoulli’s Principle
Bernoulli’s Principle• Explains how the pressure of a moving fluid (liquid or gas) varies with its speed of
motion. • States that as the velocity of a moving fluid (liquid or gas) increases, the pressure
within the fluid decreases. • Explains what happens to air passing over the curved top of the airplane wing.
Bernoulli’s Principle - 1 of 3Bernoulli’s Principle - 1 of 3
Bernoulli’s Principle - 2 of 3Bernoulli’s Principle - 2 of 3
Bernoulli’s Principle - 3 of 3Bernoulli’s Principle - 3 of 3
In-Flight Application of BernoulliIn-Flight Application of Bernoulli
Illustration of Vectors Illustration of Vectors and Resultant Vectorsand Resultant Vectors
Types of Air FoilsTypes of Air Foils
Components of an AirfoilComponents of an Airfoil
• Airfoil: a structure designed to obtain reaction upon its surface from the air through which it moves or that moves past such a structure.
• Camber: curvatures of the upper and lower surfaces of the airfoil. The camber of the upper surface is more pronounced than that of the lower surface, which is usually somewhat flat.
• Chord Line: a straight line drawn through the profile connecting the extremities of the leading and trailing edges.
• Mean Camber Line: reference line drawn from the leading edge to the trailing edge, equidistant at all points from the upper and lower surfaces.
• Leading Edge faces forward in flight and is rounded.• Trailing Edge faces aft in flight and is narrow and tapered.
Relationship of Flight PathRelationship of Flight Pathto Relative Windto Relative Wind
Angle of Attack ExamplesAngle of Attack Examples
Angle of Attack ExamplesAngle of Attack Examples
Angle of Attack and Wing StallsAngle of Attack and Wing Stalls
Air circulation around an airfoil occurs when the front stagnation point is below the leading edge and the aft stagnation point is beyond the trailing edge.
Effect of Wingtip TwistEffect of Wingtip Twist
Wingtip
Wing Root
Effect of Stall StripEffect of Stall Strip
Wingtip
Wing Root
Flaps Increase Both Lift and DragFlaps Increase Both Lift and Drag
Types ofTypes ofFlapsFlapsandand
LeadingLeadingEdgeEdge
DevicesDevices
Types of DragTypes of Drag
Parasite Drag Caused by any aircraft surface which deflects or interferes
with smooth airflow around airplane Form drag
results from turbulent wake caused by the separation of airflow from the surface of the structure
Interference drag occurs when varied currents of air over an airplane meet and interact
Skin friction drag caused by roughness of the airplane’s surfaces
Induced Drag Generated by the airflow circulation around the wing as it
creates lift
Examples of DragExamples of Drag
Examples of Reducing DragExamples of Reducing Drag
Total Drag and L/DTotal Drag and L/Dmaxmax Ratio Ratio
Ground EffectGround Effect
Result of earth’s surface altering the airflow patterns around the airplane.
Occurs within one wingspan above the ground. When in ground effect
Induced drag decreases and excess speed in the flare may cause floating.
Airplane may become airborne before it reaches its recommended takeoff speed.
Three Axes of FlightThree Axes of Flight
Longitudinal Stability and BalanceLongitudinal Stability and Balance
Longitudinal Stability Pitching motion or tendency of airplane to move about its
lateral axis. Determined by the location of the center of gravitycenter of gravity in
relation to the center of pressurecenter of pressure. Center of Pressure
Point along wing chord where lift is considered to be concentrated.
Sometimes called the center of liftcenter of lift. Center of Gravity
Determined by the distribution of weight, either by design or by the pilot.
Can affect longitudinal stability.
Center of PressureCenter of Pressure
Three Axes of FlightThree Axes of Flight
Center of Gravity (CG)
CG Range - Forward CG & Aft CGCG Range - Forward CG & Aft CG
CG Range - Forward CG & Aft CGCG Range - Forward CG & Aft CG
Longitudinal StabilityLongitudinal Stability
• Quality that makes an aircraft stable about its lateral axis.• Involves the pitching motion as the aircraft’s nose moves up
and down in flight. – A longitudinally unstable aircraft has a tendency to dive or climb
progressively into a very steep dive or climb, or even a stall.
– An aircraft with longitudinal instability becomes difficult and sometimes dangerous to fly.
• Static longitudinal stability or instability in an aircraft, is dependent upon three factors:– Location of the wing with respect to the CG
– Location of the horizontal tail surfaces with respect to the CG
– Area or size of the tail surfaces
Longitudinal StabilityLongitudinal Stability
Horizontal StabilizerHorizontal Stabilizerand Tail Down Forceand Tail Down Force
Static StabilityStatic Stability
• Initial tendency, or direction of movement, back to equilibrium.– Refers to the aircraft’s initial response when disturbed from a
given angle of attack (AOA), slip, or bank. • Positive static stability
– the initial tendency of the aircraft to return to the original state of equilibrium after being disturbed
• Neutral static stability– initial tendency of the aircraft to remain in a new condition after its
equilibrium has been disturbed• Negative static stability
– initial tendency of the aircraft to continue away from the original state of equilibrium after being disturbed
Static StabilityStatic Stability
Dynamic StabilityDynamic Stability
• Dynamic stability refers to the aircraft response over time when disturbed from a given angle of attack (AOA), slip, or bank. It has three subtypes:
• Positive dynamic stability– over time, the motion of the displaced object decreases in
amplitude and, because it is positive, the object displaced returns toward the equilibrium state.
• Neutral dynamic stability– once displaced, the displaced object neither decreases nor
increases in amplitude. A worn automobile shock absorber exhibits this tendency.
• Negative dynamic stability– over time, the motion of the displaced object increases and
becomes more divergent.
Dynamic StabilityDynamic Stability
Horizontal StabilizerHorizontal Stabilizerand Tail Down Forceand Tail Down Force
Center ofGravity
Center of Lift
Directional StabilityDirectional Stability
Directional Stability Stability about the airplane’s vertical axis. Steadying influence of the vertical stabilizer.
Acts like a weather vane.
Interaction of Directional Stability with Lateral Stability Dutch Roll
Combination of rolling / yawing oscillations caused by control inputs or wind gusts.
Dihedral (lateral stability) more powerful than directional stability.
Spiral Instability Directional stability more powerful than lateral stability.
Lateral StabilityLateral Stability
Lateral Stability Stability about the airplane’s longitudinal axis (nose to tail). Tendency to resist lateral roll.
Dihedral Common design approach to build in lateral stability. Upward angle of the wings with respect to the horizontal. Less dihedral in high wing airplanes than in low wing
aircraft. Cessna 172 versus Mooney M20J
Keel Effect Steadying influence of side area of the fuselage and the
vertical stabilizer.
Illustration of DihedralIllustration of Dihedral
Illustration of DihedralIllustration of Dihedral
Airspeed Indicator (ASI) and V-speedsAirspeed Indicator (ASI) and V-speeds
V-speeds Vx = best angle * Vy = best rate * Va = maneuvering * Vfe = flap extend Vs = stall clean configuration Vso = stall landing configuration Vno = max structural cruising speed Vne = never exceed speed
* not on ASI
• Arcs white
bottom = Vso
top = Vfe
green bottom = Vs top =
Vno yellow
bottom = Vno
top = Vne
red line = Vne
Airspeed Indicator (ASI)Airspeed Indicator (ASI)
Types of AirspeedTypes of Airspeed
Indicated Airspeed (IAS) Speed indicated on ASI Uncorrected for instrument and installation errors No variations in air density
Calibrated Airspeed (CAS) Corrected for instrument and installation errors
True Airspeed (TAS) CAS corrected for
altitude nonstandard temperature
Groundspeed (GS) Speed over the ground TAS adjusted for wind
Types of StallsTypes of Stalls Proficiency Stalls (Student Mastery)
Power-off stalls: landing conditions & configuration Power-on stalls: take-off conditions & configuration
Demonstration Stalls (CFI Demonstration) Secondary stalls Cross-control stalls Accelerated stalls
Stall Recovery Decrease angle of attack Smoothly apply maximum power Adjust power & configure for normal, coordinated flight.
V-g DiagramV-g Diagram
V-g DiagramV-g Diagram
SpinsSpins
Definition of a Spin Aggravated stall accompanied by autorotation. One wing stalled more than the other wing.
Types of Spins Erect Inverted Flat
Stages or Phases Incipient spin Fully developed spin (steady-state) Spin recovery
Spin RecoverySpin Recovery
Throttle to idle Neutralize ailerons Determine direction of spin via turn coordinator Full opposite rudder Briskly apply forward elevator pressure Neutralize rudder Gradually apply back elevator pressure
Left-Turning TendenciesLeft-Turning Tendencies
• The left turning tendency of the airplane is made up of four elements which cause or produce a twisting or rotating motion around at least one of the airplane’s three axes.
– Torque reaction from engine and propeller,– Corkscrewing effect of the slipstream,– Gyroscopic action of the propeller, and– Asymmetric loading of the propeller (P-factor).
Left-Turning TendenciesLeft-Turning Tendencies
Left-Turning TendenciesLeft-Turning Tendencies
Airplanes in GlideAirplanes in Glide
Best Glide Speed See POH C-172 = 70 knots
Glide Ratio See POH E.G. glide ratio of 10:1 means airplane will travel 10,000
feet (1.6 nm) horizontally for each 1,000 feet of altitude lost Typical Cessna 172 9.1 : 1 Typical Piper Cherokee (Warrior) 11.5 : 1
Factors Affecting Glide Weight Configuration Wind
Types of TurnsTypes of Turns
Shallow turns Less than 15° Tendency to return to straight-and-level flight
(positive static stability) Medium turns
15° or more but not more than 30° Tendency to return to remain in the turn
(neutral static stability) Steep turns
More than 30°, usually 45° Tendency to steepen the turn (overbanking tendency)
(negative static stability)
Rate and Radius of TurnsRate and Radius of Turns
Rate of Turn Amount of time it takes an airplane to turn a specified
number of degrees If airspeed increases with angle of bank constant, then
rate of turn decreases. If angle of bank increases with airspeed constant, then
rate of turn increases. Radius of Turn
Amount of horizontal distance an airplane uses to complete a turn
If airspeed increases with angle of bank constant, then radius of turn increases.
If angle of bank increases with airspeed constant, then radius of turn decreases.
Forces Acting on Airplane in A TurnForces Acting on Airplane in A Turn
Normal, Slipping and Skidding TurnsNormal, Slipping and Skidding Turns
Bank Angle Effect on Load FactorBank Angle Effect on Load Factor
Bank Angle Impact on Load FactorBank Angle Impact on Load Factor
Bank Angle Impact on Load Factor Bank Angle Impact on Load Factor and Stall Speedand Stall Speed
Components of LiftComponents of Lift
• Division of Lift Vertical Component of Lift Horizontal Component of Lift
• Offsetting Forces Vertical Component of Lift Weight Horizontal Component of Lift Centrifugal Force Total Lift Load Factor
• Horizontal Component of Lift = sideward force that causes airplane to turn (centripetal force)
Effects of Division of LiftEffects of Division of Lift
• Division of lift reduces lift supporting airplane, produces altitude loss unless: Increase angle of attack Increase airspeed Increase angle of attack and airspeed Trim up when passing 30º bank into 45º bank Roll-out to 30º as necessary to regain altitude
Load Factor, Stall Speed, & Bank AngleLoad Factor, Stall Speed, & Bank Angle
Stall speed increases by – 30° bank = load factor of 1.1 1.05 * VS
– 45° bank = load factor of 1.4 1.20 * VS
– 60° bank = load factor of 2.0 1.40 * VS
Maximum bank angle = 50º -- 60ºLoad Factor versus Bank Angle
– 60° bank = 2 g– 70° bank = 3 g– General Aviation airplanes stressed for max 3.8 g
LoadFactor
Limit Load FactorLimit Load Factor
Definition of Limit Load Factor Amount of stress or load factor that an airplane can
withstand before structural damage or failure occurs. Normal Category
3.8 positive G’s 1.52 negative G’s
Utility Category 4.4 positive G’s 1.76 negative G’s
Acrobatic Category 6 positive G’s 3 negative G’s
References and InformationReferences and Information
• Downloading This PresentationDownloading This Presentation– http://williamjdoylejr.net/pvt/Aerodynamics.ppt– http://williamjdoylejr.net/pvt/DoyleWJ_CFII/
• FAA Airplane Flying Handbook – FAA-H-8083-3AFAA Airplane Flying Handbook – FAA-H-8083-3A– Airplane Structure, Chapter 2
http://www.faa.gov/library/manuals/aviation/pilot_handbook/media/PHAK%20-%20Chapter%2002.pdf
– Principles of Flight, Chapter 3 http://www.faa.gov/library/manuals/aviation/pilot_handbook/media/PHAK%20-%20Chapter%2003.pdf
– Aerodynamics of Flight, Chapter 4 http://www.faa.gov/library/manuals/aviation/pilot_handbook/media/PHAK%20-%20Chapter%2004.pdf
– Flight Controls, Chapter 5 http://www.faa.gov/library/manuals/aviation/pilot_handbook/media/PHAK%20-%20Chapter%2005.pdf
• Pilot Handbook: A Comprehensive Text/Reference for All Pilots (Eighth Edition), Irvin N. Gleim, Pilot Handbook: A Comprehensive Text/Reference for All Pilots (Eighth Edition), Irvin N. Gleim, Ph.D., CFII and Garrett W. Gleim, CFII, MEIPh.D., CFII and Garrett W. Gleim, CFII, MEI
– Airplanes and Aerodynamics, Chapter 1, pp 15 – 66• Other Resources – Maj Bill DoyleOther Resources – Maj Bill Doyle
– http://home.netcom.com/~doylewj/Aviation/student_pilot_flight_training/default.htm– http://home.netcom.com/~doylewj/default.htm– http://williamjdoylejr.net/Careers/Career_Awareness_Aviation_St_Marks_2010-06-02.ppt
About the PresenterAbout the Presenter
• AviatorAviator– Commercial, Instrument, ASEL & AMEL – 3,000 hours total time; 850 hours TAA; 500 hours KFC 150; 700 hours Garmin 430,
150 hours Garmin G1000• InstructorInstructor
– CFI A&I, AGI, IGI, ASC– 1,400 hours as CFI– Cessna FITS Course and CFAI Course (G1000 for C182 and U206)– FAA PHL FSDO CFI of the Year 2009-2010
• Civil Air PatrolCivil Air Patrol– Instructor-Pilot, Check Pilot, and Check-Pilot Examiner– G1000 Project Officer
• Technologist & TeacherTechnologist & Teacher– Director of Technical Services, Hatboro-Horsham School District– Nursing Informatics Instructor, La Salle University Graduate School of Nursing
• AuthorAuthor– Two books on electronic spreadsheets, with a Russian translation– Self-study manuscript on computer concepts for nurses– Articles on gear up landings and fuel management published by FAA
The Escape PodThe Escape Pod
Cirrus
SR20
with
Ballistic
Parachute
Aim High!Aim High!But Not On Final!But Not On Final!
If you’ve ever wondered…If you’ve ever wondered…
• What are the main parts of an airplane?
• What’s a fuselage?
• What makes an airplane fly?
• How do aircraft wings work?
• How is a plane controlled?
• What is the instrument panel?
• How do you get from one place to another?…then this class is for you!
Warming Up – Soda Straw ExperimentWarming Up – Soda Straw Experiment
Courtesy of J. Elfick, University of Queensland, Australia
• Put the end of a soda straw into a glass of water or a bottle of soda
• Put your finger on the top of the straw• Lift the straw from the glass or soda
bottle.• The water or soda remains in the
straw because the effect of the air pressure up the straw is greater than the weight of the water or soda.
• Remove your finger and the water or soda falls out of the straw.
• Do you know why this is important to aviation?
Why the Soda Straw is ImportantWhy the Soda Straw is Important
• Pilots are taught that airplane fuel gauges are unreliable
• Do you know at what point the gauges are required by law to be accurate?
• The straw becomes a calibrated plastic tube
• The calibrations represent the gallons of gas remaining in the fuel tank
• Each wing has a fuel tank.• In the airplane that I currently fly:• Each wing holds 43½ gallons• Total fuel is 87 gallons• Fuel consumption is 12½ to 15
gallons per hour• So how long can I stay in the air?
What Are the Main Parts of an AirplaneWhat Are the Main Parts of an Airplane
What Are the Main Parts of an AirplaneWhat Are the Main Parts of an Airplane
Main Parts of an Airplane - DefinitionsMain Parts of an Airplane - Definitions
• Airplane – An airplane is a vehicle heavier than air, powered by an engine, which travels through the air via the forces of lift and thrust.
• Fuselage – The fuselage is the central body portion of an airplane, designed to accommodate the pilot/crew and the passengers and/or cargo.
• Cockpit – In general aviation airplanes (all except those operated by airlines and the military) the cockpit is usually the space in the fuselage for the pilot and passengers; in some aircraft it is just the pilot’s compartment.
• Propeller – A propeller is a rotating blade on the front of the airplane. The engine turns the propeller, which pulls the airplane through the air.
• Wings – Wings are the parts of airplanes that provide lift and support the entire weight of the aircraft and its contents while in flight.
Main Parts of an Airplane - DefinitionsMain Parts of an Airplane - Definitions
• Flaps – Flaps are the movable sections of an airplane’s wings that are closest to the fuselage. They move in the same direction on both wings at the same time, and enable the airplane to fly more slowly.
• Ailerons – Ailerons are the outward movable sections of an airplane’s wings. They move in opposite directions (if one goes up, the other goes down). They are used in making turns, and they control movement around the longitudinal axis (imagine a line through the airplane from the nose to the tail).
• Rudder – The rudder is the movable vertical section of the tail that controls lateral (side-to-side) movement. When the rudder moves one direction, the aircraft nose moves the same direction, while the tail moves in the opposite direction.
Main Parts of an Airplane - DefinitionsMain Parts of an Airplane - Definitions
• Horizontal Stabilizer – The horizontal stabilizer is the horizontal surface at the rear of the fuselage designed to balance the airplane.
• Elevator – The elevator is the movable horizontal section of the tail that causes the plane to move up and down. When the elevator moves one direction, the nose moves in the same direction.
• Landing Gear – A landing gear is underneath the airplane and supports it while on the ground. A landing gear usually includes a wheel and tire.
Instrument Panel – Cessna 172 SkyhawkInstrument Panel – Cessna 172 Skyhawk
Flight InstrumentsFlight Instruments
Airspeed IndicatorAirspeed Indicator Attitude IndicatorAttitude Indicator AltimeterAltimeter
Turn CoordinatorTurn Coordinator Heading IndicatorHeading Indicator Vertical Speed IndicatorVertical Speed Indicator
Flight InstrumentsFlight Instruments
What Effect Does Wind Have?What Effect Does Wind Have?
• There is always wind. The higher you climb, the stronger it gets.• You have to fly a heading that offsets the effect of the wind.• So is there relevancy here to what you study in school?
– Applicable Subject in School = Math– High School Course = Trigonometry
How Do You Calculate the Effect of Wind?How Do You Calculate the Effect of Wind?
• The E6B Flight Computer – sort of a circular slide rule.• Cost = $30
How Do You Calculate the Effect of Wind?How Do You Calculate the Effect of Wind?
• The Garmin GNS 430 – all-in-one GPS/Navigation/Communication product.• The Garmin GNS 430 does it all for you.• Cost = $9,650 installed.• Having someone else pay for this – priceless!
How Do You Calculate the Effect of Wind?How Do You Calculate the Effect of Wind?
• Online Flight Planning Tools– Look at winds for your route of
flight – Calculate the wind correction
for you automatically• Costs
– Computer– Internet connection– Annual membership in AOPA
• So is there relevancy here to what you study in school?– Applicable Subject in School =
Technology– School Courses = Computer
Applications, Internet
How Much Can an Airplane Weigh?How Much Can an Airplane Weigh?
• Each airplane has a limitation called the maximum gross takeoff weight. Some airplanes also have a maximum gross landing weight.
• This weight includes everything– Airplane (empty)– Fuel– Pilot and passengers– Baggage
• There is another component called “Balance.” The entire process is called “Weight and Balance.”
• So is there relevancy here to what you study in school?– Applicable Subject in School = Math– Elementary and Middle School = Math (Arithmetic for the “Weight” piece)– High School Course = Physics (Center of Gravity for the “Balance” piece)
What Does Balance Mean?What Does Balance Mean?
• Classic example is the playground seesaw:– Center bar is the fulcrum which is the center of gravity.– Heavier weight of “big” kid on one end overcomes lesser weight of “little” kid other end – This forces the “little” kid to go up– Is there a way to make the “big” kid go up without adding weight or changing kids?
• So is there relevancy here to what you study in school?– Applicable Subject in School = Science– High School Course = Physics (Chapter on Center of Gravity)
What Does Balance Mean for an Airplane?What Does Balance Mean for an Airplane?
• The laws of physics apply to everything.
• Calculate the airplane’s center of gravity for your flight.
• If outside the envelope, move people or baggage– Recalculate to see if that
helped• If yes, go fly
• If no, leave something or somebody behind
Excel Example of Weight & BalanceExcel Example of Weight & Balance
• So is there relevancy here to what you study in school?– Applicable Subjects in School = Science, Technology– High School Course = Physics (Chapter on Center of Gravity), Microsoft Office - Excel
