This document provides an overview of flight mechanics topics including angle of attack. It discusses the angle of attack (AOA) as the angle between the relative wind and chord line of an airfoil. Greater AOA results in greater lift but also greater drag. Higher AOA variation can cause stall from loss of lift. It recommends visualizing AOA effects using NASA's FoilSim tool. The document also outlines core topics like aircraft configurations, flight instruments, aerodynamic forces, airplane performance, stability, and dynamic stability to be covered.

1. FLIGHT MECHANICS
Presented by - Ganesh Natarajan S
Target Audience: Gate Aerospace, Aeronautical and Aerospace Engineering Students, etc.
Angle of Attack (AOA)
α
V∞

2. CORE TOPICS
Basics: Atmosphere: Properties, standard atmosphere. Classification of aircraft. Airplane (fixed
wing aircraft) configuration and various parts. Pressure altitude; equivalent, calibrated, indicated
air speeds; Primary flight instruments: Altimeter, ASI, VSI, Turn-bank indicator.
Angle of attack, sideslip; Roll, pitch & yaw controls. Aerodynamic forces and moments.
Airplane performance: Drag polar; takeoff and landing; steady climb & descent; absolute and
service ceiling; range and endurance, load factor, turning flight, V-n diagram. Winds: head, tail
& cross winds.
Static stability: Stability & control derivatives; longitudinal stick fixed & free stability;
horizontal tail position and size; directional stability, vertical tail position and size; lateral
stability. Wing dihedral, sweep & position; hinge moments, stick forces.
SPECIAL TOPICS
Dynamic stability: Euler angles; Equations of motion; Decoupling of longitudinal and lateral-
directional dynamics; longitudinal modes; lateral-directional modes.
SYLLABUS

3. Outline
Let’s Start
Angle of Attack (AOA)
Previous Lessons Primary flight instruments
Definition
• Angle of Attack (AOA)
• Insights
FoilSim AOA effect Visualization
• Symmetric Airfoil
• Cambered Airfoil
• Flat Plate
Special Question
• Why Airfoil?
• Why not flat plate?

4. Angle of Attack (AOA)
Definition
The angle between the relative wind (V∞) and the chord line (the line
connecting Leading edge [LE] & Trailing edge [TE]) is the angle of attack a
of an airfoil.
JDougMcLeanatEnglishWikipedia/CCBY-SA
(https://creativecommons.org/licenses/by-sa/3.0)
• The Angle of Attack is abbreviated as (AOA).
• It is symbolized as “α”.
• In some literature, alternate reference line is considered instead of chord line.

5. Angle of Attack (AOA)
MotionImageryStandardsBoard(MISB)/Publicdomain

6. Insights: Angle of Attack
• Unit Conversion: 1Deg ×
𝜋
180
= 0.01745Rad
• Greater Angle of Attack = Greater Lift* = Greater Drag
• Higher Angle of Attack variation results in stall (Loss of lift)!
• Zero-lift angle of attack (αL=0) varies based on the type of airfoil.
Lets Visualize the effect of
Angle of Attack! Through NASA’s FoilSim.
FoilSim Student JS: https://www.grc.nasa.gov/www/k-12/airplane/foil3.html

7. Book Reference
• Introduction to Flight, J.D. Anderson (7th Edition): Pg.No: (292,301-302,587).
Angle of Attack (AOA)

8. Summary
Angle of
Attack
FoilSim
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