NAVWEPS 00-801-80
PREFACE
The majority of aircraft accidents are due to some type of error of
the pilot. This fact has been true in the past and, unfortunately, most
probably will be true in the future. Each Naval Aviator should strive
to arm himself with knowledge, training, and exacting, professional
attitudes and techniques. The fundamentals of aerodynamics as pre-
sented in this text will provide the knowledge and background for
safe and effective flying operations. The flight handbooks for the air-
craft will provide the particular techniques, procedures, and operating
data which are necessary for each aircraft. Diligent study and continu-
ous training are necessary to develop the professional skills and tech-
niques for successful flying operations.
The author takes this opportunity to express appreciation to those
who have assisted in the preparation of the manuscript. In particular,
thanks are due to Mr. J. E. Fairchild for his assistance with the por-
tions dealing with helicopter aerodynamics and roll coupling phenom-
ena. Also, thanks are due to Mr. J. F. Detwiler and Mr. E. Dimitruk
for their review of the text material.
HUGH HARRISON HURT, Jr.
August 1959
University of Southern California
Los Angelesj Cnlif.
NAVWEPS OO-801-8O
TABLE OF CONTENTS
TABLE OF CONTENTS
PREFACE.. ,., . iii
CHAPTER I: BASIC AERODYNAMICS
WING AND AIRFOIL FORCES
PROPERTIES OF THE ATMOSPHERE. 1
Static pressure
Temperature
Density
Viscosity
Standard atmosphere
Pressure altitude
Density altitude
BERNOULLI’S PRINCIPLE AND SUBSONIC AIRFLOW.. 4
Bernoulli’s equation,
Incompressible tlow
Variation of static pressure and velocity
Kinetic and porcntial energy of flow
Static and dynamic prcssurc, 4
Factors affecting dynamic pressure
Airspeed measurement.. . .
Stagnation prcssurc
Measurement of dynamic pressure
Pitot and static sources
Indicated airspeed
DEVELOPMENT OF AERODYNAMIC FORCES..
Streamline pattern and pressure distribution.
Generatioaoflift..........................................
Circulation
Pressure distribution
....... 14
....... 14
....... 16
Airfoil terminology.
Aerodynamic force coefficient . .
‘,:
Basic lift equation 2 3
Lift coefficient
Dynamic prcssurc and surface area
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TABLE OF CONTENTS
Interpretation of the lift equation.. . . . . . . . .
Lift cocfficicnt versus angle of attack
Stall speed and angle of attack
Angle of attack versus velocity
Primary control of airspeed
. . _ . . . _ . mrfou un cnacactectsucs. . . .
Section angle of attack and lift coefficient
Ty ical section chvactctistics
E&t of thickness and cambet
Drag characteristics, . . . . . . . :.
Drag equation
Drag cocficicnt versus angle of attack
Lift-drag ratio
Power-off glide pctformancc
Airfoil drag chanwteristics.. ) . . .
Section drag cocfficicnt
Ty ical section characteristics
E 2 ect of thickness and cunbcr
Low drag sections
FLIGHT AT HIGH LIFT CONDITIONS. . . . . . . .
StaII speeds. . . . . . . . . .,. . . . . . .
Maximum lift cc&cicnt
Stall angle of attack
..,e * . . ~lrecrorwergnt....................................................
Effect of maneuvering flight,. .
Load factor ~ets~s bank angle
Stall spad versus load factor
Effect of high lift devices., .
Effect on stall speed
Stall angle of attack and stall recovery. . . . . .
HIGH LIFT DEVICES.
Types of high lift devices., .
Plain flap
S otted flap P
lit flap
Fowler flap
Slots and slats
Boundary layer control
Operation of high lift devices.
Flap retraction and extension
Chan
Effect o f
es in lift, drag, and trim
power
DEVELOPMENT OF AERODYNAMIC PITCHING MOMENTS
Pressure distribution. .~. : . ! . :
Center of pressure and aerodynamic center.
Pitching moment coefficient. . ,
Effect of camber
Effect of flaps
Relationship between center of pressure, aerodynamic centet, and
moment coefficient
Application to longitudinal stability. .
Stability and trim
Effect of supersonic flow
PW
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TABLE OF CONTENTS
FRICTION EFFECTS.
Viscous Bow..
Boundarglayers....................................................
Laminar flow
Transition
Turbulent flow
ReyooldsNumber..................................................
Definition
Skin friction versus Reynolds Number
Airflowseparatioa..................................................
Pressure distribution
Prcswrc gradient and boundary layer energy
Factors affecting separation
Scaleeffect.........................................................
Effect on aerodynamic characteristics
Reynolds Number correlation
PLANFORM EFFECTS AND AIRPLANE DRAG
EFFECT OF WING PLANFORM..
. . Descr1puon of planform
Area, span,, and chord
Aspect ratm and taper
Sweepback
Mean aerodynamic chord
Development of lift by a wing.. .
vortex system
Ti and bound vortices
I&cd flow and downwash
Scction angle of attack
Induced angle of attack
INDUCED DRAG. :
Induced angle of attack and inclined lift.
Induced drag coefficient,
Effect of lift coefficient
Effect of aspect ratio
Effectoflift........................................................
Effea of altitude..
EffectofsPeed......................................................
Effect of aspect ratio.
Lift and dra
Influcncc of ow aspxt ratio configurations f
characteristics
EFFECT OF TAPER AND StiEEPtiACK.
Spanwise lift distribution
localinducedflow.................................................
Effect on lift and drag characteristics. .‘,
STALL PATI’ERNS.
Pnvorablestallpattern..............................................
EffeaofpIanform..................................................
Taper Sweepback
Modifications for stall characteristics.
2;
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