01 basicaerodynamics spanish

7/29/2019 01 Basicaerodynamics Spanish

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AERODINMICA YFUNDAMENTOS DE VUELO

Aerodinmica BsicaA. La Atmsfera

B. FsicaC. El Perfil AerodinmicoD. Sustentacin & Resistencia

E. EstabilidadF. Controles de Vuelo


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AerodinmicaBsica

Aerodinmica BsicaA. La AtmsferaB. FsicaC. El PerfilD. Sust. y ResistenciaE. Estabilidad

F. Controles de Vuelo

Aerodinmica:

El estudio de objetos en movimientoa travs del aire y las fuerzas queproduce o cambia tal movimiento.


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La Atmsfera

Para volar, necesitamos crear unafuerza hacia arriba igual al peso de laaeronave usando la atmsfera.

Esta fuerza proviene de la accin de laatmsfera sobre un perfil aerodinmico.



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La Atmsfera

Est constituida de una mezcla de gases 21% Oxigeno.

78% Nitrgeno.

El resto es mezcla de gases inertes (Argn,Nen, etc.)



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La Atmsfera

La mezcla permanece constante sin tener encuenta la altitud.

El peso del aire cambia cuando la altitud vara.

Menos peso por encima cuando estamos msarriba = menos PRESIN ATMOSFRICAejercida sobre los objetos.



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La Atmsfera

CONDICIONES DE

DA ESTANDAR. International CivilAeronautics

Organization (ICAO)tiene medidasestndar para datosde prueba.



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CONDICIONES DE

DA ESTANDAR. Permite comparar

datos de pruebadesde una ubicacino da a cualquierparte del mundo.



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La Atmsfera


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DA ESTNDAR

Presin

Es una fuerza creada por el peso de laatmsfera sobre un objeto.

Es medido enpulgadas HG, mm HG, PSIomilibares.



La Atmsfera

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pulg-Hg o mm-Hg

Un tubo es llenado conMercurio (Hg) y luego

invertido en un envasede Mercurio.

El Hg se elevar y elpeso es medido.



DA ESTNDAR

Presin

La Atmsfera

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Bajo condiciones ISA, la atmsfera puede soportar

una columna de mercurio de 29.92 de alto.


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pulg-Hg o mm-Hg

En un da estndar aNIVEL DEL MAR (cero

altitud), el peso ser29.92 pulgadas - 29.92pulg-Hg) o 760milmetros (760 mmHg).



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DA ESTNDAR

Presin

La Atmsfera

A di i B i


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pulg-Hg o mm-Hg

Esto es llamado unamedida ESCALA

ABSOLUTA como unVACO que se formaren la parte superior deltubo (= PRESIN

ABSOLUTA CERO)



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DA ESTNDARPresin

La Atmsfera

A di i B i


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La Presin Atmosfricadisminuir aprox. 1pulg-Hg por cada1,000 pies de

incremento en altitud.

Known as the LAPSERATE



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DA ESTNDARPresin

La Atmsfera

A di i B i


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Un ALTIMETRO mide lapresin absoluta ymuestra el resultado enpies Sobre el Nivel del

Mar (ASL).

Ntese la VENTANAKOLLSMAN (regulacinpara varias condiciones

locales)



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DA ESTNDARPresin

La Atmsfera

A di i B i


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PSI

Es una medida deFUERZA / AREA

Las unidades mscomunes son LIBRASPOR PULGADACUADRADA.



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DA ESTNDARPresin

La Atmsfera

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PSI

En un da estndar alNivel del Mar, la

atmsfera presionasobre los objetos conuna fuerza de 14.69libras por pulgadacuadrada de rea.



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DA ESTNDARPresin

La Atmsfera

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PSI

Desde la del aire enla atmosfera est por

debajo de los 18,000pies ASL, la presinall es 7.34 psi.



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DA ESTNDARPresin

La Atmsfera

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PSI

Es medida por unaescala Absoluta y es

etiquetada como PSIA.



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DA ESTNDARPresin

La Atmsfera

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Manmetro: usa laPresin Atmosfricacomo cero dereferencia (= PSIG)



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DA ESTNDARPresin

La Atmsfera

El indicador de presin es referenciado desde la

presin atmosfrica.

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Milibares

Son usados por Meteorologistas (meteorlogo militar)

En un Da Estndar a Nivel del Mar es 1013.2 mbs.

1 milibar es aproximadamente igual a 0.75 pulg-Hg.



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DA ESTNDARPresin

La Atmsfera

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Temperatura Son usadas

Cuatro escalas.

CELSIUS (usado

como gradosCentgrados)



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DA ESTNDARLa Atmsfera

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Cuatro escalas.

KELVIN (Celsius

Absolutos)

Aerodinmica BsicaA. La AtmsferaB. FsicaC. El PerfilD. Sust. y ResistenciaE. EstabilidadF. Controles de Vuelo

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Cuatro escalas.

FARENHEIT


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Temperatura Son usadas Cuatro

escalas.

RANKINE

(Farenheit Absoluto)


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Da estndar alnivel del mar:

- 15 Celsius

- 59 Fahrenheit- 288 Kelvin

- 519 Rankine


Temperatura

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Altitud aumenta, latemperaturadisminuye.

3.54 F o 2 C porcada 1,000 pies.

Gradiente detemperatura

vertical Adiabtica.


Temperatura

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Es la cantidad de humedad en el aire

Medida por la HUMEDAD RELATIVA.

Es la comparacin de humedad presente a la

cantidad en % de aire que puede permanecer.

La Mxima cantidad es directamente proporcional ala temperatura (Mayor Temp. = ms humedad a lamismo % de Humedad Relativa)


Humedad

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En un da estndar hay 0% de humedad o se diceque el Aire est seco.


Humedad

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Es la medida de Masa por unidad de Volumen.

La Masa es la cantidad de materia de un objeto.

Puede pensarse como un nmero de molculas.

El Peso es el efecto de la Gravedad sobre la masa.

Cuando se considera a objetos cerca a la superficiede la Tierra, el peso y la masa son usados

intercambiables en Aerodinmica.

A. La AtmsferaB. FsicaC. El PerfilD. Sust. y ResistenciaE. EstabilidadF. Controles de Vuelo

Densidad

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La densidad del Aire es oficialmente medida enSLUGS PER CUBIC FOOT.

Da estndar a Nivel del Mar = .002378 slugs/ft3

Su smbolo es la letra griega Rho ( ) Factor principal en el desarrollo de la Sustentacin.

Vara directamente con la Presin Atmosfrica e

inversamente con la Temperatura.


Densidad

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La Aviacin usa laDENSIDAD ALTITUDcomo una medidaimportante de ladensidad que afectaal vuelo.


Altitud Densidad

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Es una medida de laperformance de unaaeronave (distanciade decolaje, distancia

aterrizaje, capacidadde transporte depeso, etc.)


Altitud Densidad

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La altitud en un da

estndar tiene lamisma densidad ascomo las condicionesambientales

Es la altitud en la que

la aeronave piensa

que est.


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Altitud Densidad

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Calculada usandouna carta de altituddensidad.

Debemos conocer laALTITUD PRESIN yla Temperatura

Ambiente.


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Altitud Densidad

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La Altitud Presin esla altitud en el DaEstndar en el cual lapresin atmosfrica

coincide con lapresin atmosfricalocal.


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Altitud Presin

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Por Ejemplo: A unapresin ambiente de:

28.92 pulg-Hg

La presin disminuye1 pulg-Hg/1000 pies,

Altitud Presin =1,000 pies ASL.


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Altitud Presin

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Ejemplo de AltitudDensidad: La AltitudPresin puede sertambin determinada

por la ubicacin queests regulando laventana Kollsmanpara 29.92 y leyendo

la altitud.


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Altitud Densidad

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Ejemplo:

Presin = 25.92pulg-Hg (= ? pies

de Altitud Presin) = 4,000 pies

SL (29.92) actual(25.92) = 4 pulg. x

1000 pies.


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Altitud Densidad

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Ejemplo:

Presin = 25.92pulg-Hg (= ? pies de

Altitud Presin)

= 4,000 pies

Temperatura = 80 F


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Altitud Densidad

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Ejemplo:

Altitud densidad =6,500 pies.

6,500


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Altitud Densidad



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Es afectado por laHumedad Relativa.

Vapor de agua tienecerca del 62% del pesodel aire = mayorhumedad = menordensidad de aire =Mayor Altitud Densidad

= slo afectado por 5%.


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Altitud Densidad



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Generalmentedecimos:

TENGA CUIDADO

DE LASCONDICIONES DEALTA HUMEDAD YCALOR.


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Altitud Densidad

Aerodinmica BsicaA La AtmsferaA di i


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Principio de Bernoulli

Si la energa total del aire que fluyepermanece constante, cualquier incrementoen la energa CINTICA crea una disminucinde la energa POTENCIAL.

Por la LEY DE LA CONSERVACIN DE LAENERGA, las energas en el flujo son slocambiadas.


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Leyes de la Fsica que afectan la Aerodinmica



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La energacintica esmedida comoVelocidad.

La energaPotencial esmedida comoPresin.



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En la gargantadel venturi:

La Velocidad

aumenta ya que

todo el aire tieneque pasar almismo tiempo =la presin

disminuye.



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Primera Ley:

Ley de la Inercia

Un cuerpo en reposo tiende a permanecer en

reposo y un cuerpo en movimiento tiende apermanecer en movimiento, hasta que unafuerza externa modifique su estado.

Leyes de Newton


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Leyes de Newton


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Segunda Ley:

Ley de la Aceleracin

La aceleracin de un cuerpo es directamente

proporcional a la fuerza aplicada einversamente proporcional a la masa delcuerpo o a=F/m.

Entonces F = ma



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Leyes de Newton


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Tercera Ley:

Ley de la Accin y Reaccin

Para cada fuerza de accin existe una fuerza

igual y de sentido opuesto.

BasicIII. Basic Aerodynamics

A The Atmosphere


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9/7/2013 Author: Harry L. Whitehead 48

BasicAerodynamics

A. The AtmosphereB. PhysicsC. The AirfoilD. Lift & DragE. Stability

F. Large Aircraft FlightControlsThe Airfoil

Flight ForcesAs we looked at

before, there are fourforces being applied toan airplane in flight:

Lift (up)

Weight (down)

Thrust (forward)

Drag (aft)


A The Atmosphere


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BasicAerodynamics



Flight ForcesIn order to understand these forces, we need to look at

VECTORS:


A The Atmosphere


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BasicAerodynamics



Flight ForcesA Vector is an arrow whose length shows a value and it

points in the direction the value is being applied


A The Atmosphere


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BasicAerodynamics



Flight ForcesTo combine vectors, we place them with their starting

points joined (as on the left below)


A The Atmosphere


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BasicAerodynamics



Flight ForcesAnd by COMPLETING THE SQUARE we can get the

RESULTANT vector (the combination of the other two)


A The Atmosphere


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BasicAerodynamics



Flight ForcesIf two forces are exactly opposing each other (such as Lift

and Weight) and have the same value, the resultant is zero


A The Atmosphere


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Author: Harry L. Whitehead 54

BasicAerodynamics



Flight ForcesIn STRAIGHT AND

LEVEL,UNACCELERATEDFLIGHT, Thrust and Dragare equal, Lift and Weight

are equal, and the aircraftcontinues in a straight linewith no change in altitude

The forces are said to be

in EQUILIBRIUM


A The Atmosphere


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BasicAerodynamics



Flight ForcesIn order to climb, we

must increase the LiftVector so there is nolonger an equilibriumbetween Lift and Weight

The Resultant of thetwo is an upward force


A The Atmosphere


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BasicAerodynamics



Flight ForcesIn order to go faster

(Accelerate), we mustincrease the Thrustvector to get a Resultantforward

Etc.


A. The Atmosphere


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BasicAerodynamics



Flight ForcesThrust is created by the

POWERPLANT andPROPELLER

Weight is the effect ofGravity on the aircraft

Drag is created bymovement of the aircraft

Lift is created by theAirfoils used as Wings


A. The Atmosphere


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BasicAerodynamics



An Airfoil is a speciallydesigned surface which

produces a reaction toair flowing across it

Two theories:

Bernoullis Principle

Newtons Laws


A. The Atmosphere


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BasicAerodynamics



Subsonic airfoils can beAsymmetrical or

SymmetricalMost airplanes useAsymmetrical wings

Blunt, roundedLEADING EDGE

Max. thickness about1/3 of distance from L.E.to TRAILING EDGE


A. The Atmosphere


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BasicAerodynamics

pB. PhysicsC. The AirfoilD. Lift & DragE. Stability


There are many basic airfoil shapes


A. The Atmosphere


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BasicAerodynamics




Early were very thin with definitecamber

The Clark-Y was the standard throughthe 1930s

NACA developed the modern

asymmetrical shape in the 30s and itwas used for decades = smootherairflow and greater lift with less drag


A. The Atmosphere


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BasicAerodynamics




As aircraft startedto get near Mach1, the subsonicshapes causedshock waves to

form and destroylift and increasedrag tremendously

Supersonicairfoils weredesigned withsharp Leading andTrailing edges and

the max thicknessabout of thechord distance


A. The Atmosphere


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BasicAerodynamics




Next came the Supercritical design

Reduces the velocity of the airover the upper surface and delaysthe drag rise occurring with theapproach of Mach 1

NASA developed the GAW series forGeneral Aviation aircraft and givehigher lift with lesser drag than themodern


A. The Atmosphere


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BasicAerodynamics

B. PhysicsC. The AirfoilD. Lift & DragE. Stability

F. Large Aircraft FlightControlsLift and Drag

In order to generate Lift,an Airfoil must have an

ANGLE OF ATTACK (

)This is defined as theangle between theCHORD and theRELATIVE WIND (=opposite the FLIGHTPATH)


A. The Atmosphere


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BasicAerodynamics




ANGLE OF ATTACK (

)Dont confuse this with

the ANGLE OFINCIDENCE

The angle formedbetween the Chordand the Longitudinal

Axis of the airplane


A. The Atmosphere


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BasicAerodynamics




ANGLE OF ATTACK (

)If the is positive =the Leading Edge ishigher than the TrailingEdge = generate Lift inthe Upward direction

Negative =downward Lift


A. The Atmosphere


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BasicAerodynamics




ANGLE OF ATTACK (

)As the increases, theamount of Lift alsoincreases

Airfoil simulation


A. The Atmosphere
http://localhost/var/www/apps/conversion/tmp/scratch_10/Foilsim/FoilSim.htmlhttp://localhost/var/www/apps/conversion/tmp/scratch_10/Foilsim/FoilSim.html


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BasicAerodynamics




ANGLE OF ATTACK (

)

This can be shown graphically using theCOEFFICIENT OF LIFT or CL


A. The Atmosphere


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BasicAerodynamics




ANGLE OF ATTACK (

)

Notice the CL is positive even to a small negative


A. The Atmosphere


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BasicAerodynamics




ANGLE OF ATTACK (

)

And the CL peaks at some positive


A. The Atmosphere


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BasicAerodynamics




ANGLE OF ATTACK ()

Also, the CL starts to drop off if the gets higher

This is called a STALL and starts at CLmax or CRITICAL


A. The Atmosphere


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BasicAerodynamics




ANGLE OF ATTACK ()

Stall is a SEPARATION OF AIRFLOW from theupper wing surface = rapid decrease in lift


A. The Atmosphere


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BasicAerodynamics




ANGLE OF ATTACK ()

This occurs at the same regardless of speed,aircraft weight, or flight attitude


A. The AtmosphereB Ph i


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BasicAerodynamics




ANGLE OF ATTACK ()

To eliminate this condition = reduce the belowcritical




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BasicAerodynamics



Other Factors Affecting Lift:

Airspeed

Faster = increased LiftLift is increased as the square of the speed

For example:

At 200 mph a wing has 4 times the lift of the

same airfoil at 100 mphAt 50 mph the lift is as much as at 100 mph

Airfoil simulation




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BasicAerodynamics


F. Large Aircraft FlightControlsLift and DragOther Factors Affecting Lift:

Wing Planform

View of the wing from above or below




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BasicAerodynamics



Wing Planform

Rectangular: excellent slow flight and stall occursfirst at root of wing (= good aileron control)


A. The AtmosphereB Physics


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BasicAerodynamics



Wing Planform

Elliptical: most efficient = least drag for given size butdifficult to manufacture and stalls all along Trail. Edge




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BasicAerodynamics



Wing Planform

Modified (or Moderate) Tapered: more efficient thanRectangular and easier to build than Elliptical but stillstalls along Trailing Edge




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BasicAerodynamics



Wing Planform

SweptBack (and Delta): Good efficiency at highspeed but not very good at low




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BasicAerodynamics



Camber

Curve of the wingIncreased Camber = increased airflow velocity overthe top surface and more downwash angle = more lift

It also tends to lower the Critical

Trailing Edge Flaps use this to allow more lift at aslower airspeed for landing and takeoff

Airfoil simulation




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as cAerodynamics



Aspect Ratio

Is the Ratio of theWings SPAN to theaverage Chord

Higher Aspect Ratio

(long and skinny) =increased lift and lowerstalling speed

Used on Gliders andTR-1 spy plane




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AerodynamicsB. PhysicsC. The AirfoilD. Lift & DragE. Stability


Wing Area

Is the total surface area of the wingsMust be sufficient to lift max weight of the aircraft

If wing produces 10.5 pounds of lift per squarefoot at normal cruise speed = needs Wing Area of

200 square feet to lift 2,100 pounds of weight

Airfoil simulation




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F. Large Aircraft FlightControlsLift and DragDrag

Is the force opposing Thrust

Is the force trying to hold the aircraft back as it fliesand generally limits the maximum airspeed

Is created by any aircraft surface that deflects orinterferes with the smooth air flow around the aircraft

Drag is classified as two types:Induced

Parasite




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F. Large Aircraft FlightControlsLift and DragInduced Drag

The Airfoil shape (type of airfoil and amount of

Camber) and Wing Area create a force which comesfrom the same forces as those which create Lift

It is Directly Proportional to the Angle of Attack ()




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As increases, the high

pressure on the bottom ofthe wing flows around thewing tips and fills in

some of the low pressureon top

This creates a WINGTIPVORTEX and destroyssome of the wings lift or

increases its drag


A. The AtmosphereB. Physics


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The strength of the

Vortex is proportional toaircraft speed, weight,and configuration

These can be dangerous

for small aircraft flyingbehind a large aircraft




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This effect can be reducedby installing WINGLETS onthe tips of the wings

Reduce the Vortex =

increased lift andreduced drag




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This effect can alsobe reduced byinstalling TIPTANKS on the tipsof the wings




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And/or by installingDROOPED TIPS

Used on STOL(Short Take Off/

Landing) aircraft orthose designed forheavy and slowflight




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Aerodynamicsy

C. The AirfoilD. Lift & DragE. Stability


This can also be

shown by looking at theCOEFFICIENT OFDRAG (CD) of the airfoil

CD is proportional toAngle of Attack () andincreases as increases




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Aerodynamicsy


F. Large Aircraft FlightControlsLift and DragAngle of Attack and Drag

By combining the CL and CDcurves we get a Family ofcurves for any given airfoil

Includes a combination known as Lift-to-Drag Ratio (L/D)




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Aerodynamicsy



Peak L/D (L/Dmax) occurs at a given which is the mostefficient for the airfoil to operate at




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Aerodynamicsy



Unfortunately, this may be at too low an to generateenough lift to fly (may not be able to fly fast enough)




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AerodynamicsC. The AirfoilD. Lift & DragE. Stability

F. Large Aircraft FlightControlsLift and DragParasite Drag

Is the drag produced by the aircraft itself and is

proportional to AirspeedIs disruption of the airflow around the aircraft

4 types:

Form Drag

Skin Friction DragInterference Drag

Profile Drag




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Form Drag

Created by any structure which extends into theairstream

Is directly proportional to the size and shape ofthe structure

Includes struts, antennas, landing gear, etc.Streamlining reduces Form Drag




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Skin Friction Drag

Caused by the roughness of the aircrafts skinIncludes paint, rivets, skin seams, etc.

Causes small swirls (eddies) of air = drag

Improved by flush riveting and cleaning and

waxing the skin

BasicIII. Basic AerodynamicsA. The Atmosphere

B. Physics


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Interference Drag

Occurs when various air currents around theaircraft structure intersect and interact with eachother

Example: mixing of air where fuselage and

wings meetImproved by installing FAIRINGS


B. Physics


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Profile Drag

Drag formed by the Frontal Area of the aircraftCant be changed or affected by anything except

Retractable Landing Gear


B. Physics


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Combined Parasite

Drag Airspeed EffectParasite Dragincreasesexponentially asairspeed increases

IS LOWEST ATLOW AIRSPEEDSand increasesrapidly


B. Physics


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Can best be reduced

by Retractable LandingGear & streamlining

Weight andcomplication is morethan compensated bydecrease in ParasiteDrag at higherairspeeds


B. Physics


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F. Large Aircraft FlightControlsLift and DragTotal Drag

Induced Drag is also

somewhat dependenton Airspeed (indirectly)

Since it is InverselyProportional to andsince the is highest atlow airspeeds = InducedDrag is highest at lowairspeeds and drops offrapidly


B. Physics


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By combining the two

Drag curves, we get TotalDrag

At low airspeeds, InducedDrag predominates socurve goes down

At higher airspeeds,Parasite Dragpredominates so curvegoes up


B. PhysicsC f


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At some airspeed it will

be at its lowest value =most efficient airspeedto fly at = best Lift/DragRatio or L/DmaxHowever, like L/D

max

when looking at the curve, it may not bepossible to operate atthis airspeed


B. PhysicsC Th Ai f il


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F. Large Aircraft FlightControlsLift and DragOther Design Considerations

Other factors affect the structure and design of an

aircraft while in flight besides just Lift and DragThese are:

Load Factor

Propeller Factors

Engine TorqueGyroscopic Precession

Asymmetrical Thrust

Spiraling Slipstream




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F. Large Aircraft FlightControlsLift and DragLoad Factor

Load Factor is a

function of Bankingan aircraft

You can also thinkof it as creating acurved flight path =CENTRIFUGALFORCE puts moredownward force(LOAD) on the

structure




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So in order to

maintain altitude =need to pull back onthe yoke or stick andincrease theengines power to

increase the overallLift component




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Load Factor is the

Ratio of the loadsupported by the wingsto the actual weight ofthe aircraft

Below about 20oBank Angle it is equalto 1G in force

= the weight is notbeing increased


B. PhysicsC The Airfoil


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As the Bank Angle

increases above thatthe G-force also goesup exponentially

For example: at about60o of Bank, the LoadFactor is 2

The wings feel theaircraft weighs twiceas much as normal




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The FAA establishes

LIMIT LOAD FACTORSfor airplanes to bedesigned to

= the maximum LoadFactor the aircraft canwithstand withoutpermanent deformationor structural damage




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For a NORMAL

CATEGORY airplane =3.8 positive Gs and1.52 negative Gs

For a UTILITY

CATEGORY = 4.4positive Gs and 1.76negative Gs




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For anACROBATIC

CATEGORY airplane =6 positive Gs and 3negative Gs

BasicA d i

III. Basic AerodynamicsA. The AtmosphereB. PhysicsC The Airfoil


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F. Large Aircraft FlightControlsLift and DragPropeller Factors: Torque

Torque is a force

applied to the airplanefrom the Reaction tothe spinning Propeller(Newtons 3rd Law)

It causes a roll to theleft = opposite of thenormal rotation of U.S.designed engines

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F. Large Aircraft FlightControlsLift and DragPropeller Factors: Torque

On single-engine

airplanes, its commonto use aileron trim tabsto compensate

On multi-engineairplanes, its common

for the engines torotate in oppositedirections whichcancels out the Torque

Effect

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F. Large Aircraft FlightControlsLift and DragPropeller Factors: Gyroscopic Precession

A rotating Propeller

also acts like aGYROSCOPE andexhibits two gyroscopiccharacteristics:

RIGIDITY INSPACEPRECESSION

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Precession is thephenomenon whichsays that any forceapplied to a Gyroscopeis felt 90o later indirection of rotation

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Any rapid change inaircraft pitch = aprecessive forceapplied to the prop.

Most commonlyfelt by ConventionalGear airplanes justprior to Takeoffwhen the tail wheelis raised

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III. Basic AerodynamicsA. The AtmosphereB. PhysicsC. The Airfoil


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This causes adownward force(action) applied to theprop

Which causes areaction 90o later =

yaw to the left

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F. Large Aircraft FlightControlsLift and DragPropeller Factors: Asymmetrical Thrust

At high aircraft anglesof attack and duringrapid climbs, the propblades see differingangles of attack duringtheir rotation

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The side of the propdisk on which the

prop blade isdescending has ahigher than theascending blade =

more liftNOTE: rotation isclockwise as viewedfrom the pilots seat

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AerodynamicsC e oD. Lift & DragE. Stability


This change in comes from the vertical movement anda corresponding change in Relative Wind of the airfoil

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Aerodynamics D. Lift & DragE. Stability


Since the airfoil (prop) is rotating in addition to flying, theRelative Wind is now made of two factors:

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The Flight Path vectorand a vertical (rotation) vector

Descending blade (right side) = vertical vector is down

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Which gives us a new Relative Wind and a higher

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Since the descending(right) side of the prophas a higher it is alsoproducing more Thrust

The opposite occurson the ascendingside

and it produces lessThrust = tendency to yaw to

left in rapid climb

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F. Large Aircraft FlightControlsLift and DragPropeller Factors: Spiraling Slipstream

On a single-engineairplane, theSLIPSTREAM from thepropeller wraps itself

around the fuselage in aSpiraling manner

It will generally thenstrike the left side of theVertical Stabilizer andcause a yaw to the left

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Since this is a functionof how much air the propis pushing which isdirectly proportional tothe Thrust beingproduced = more yaw at

higher power settings

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Its not uncommon to

find the Vertical Stabilizerinstalled with a slightoffset to the left to causea constant compensatingforce

This is usually set up tobalance the Slipstreamaffect during Cruise flight

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F. Large Aircraft FlightControls

01 basicaerodynamics spanish

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