1. Dr. R.A. Bartholomew - Civil Air Patrol, New Jersey Wing
Cadet Phase I & II Aerospace Dimensions Introduction to Flight (Module 1)
Session 1:
Chapter 1 ‘Introduction to Flight’ (For all Cadets that have not yet passed corresponding test, and Cadet Mentors)
Activity
Additional material for Cadet Officers only
Session 2:
Chapter 2 ‘To Fly by the lifting power of rising air’
Chapter 3 ‘Balloons - They create their own thermals’ (For all Cadets that have not yet passed corresponding test, and Cadet Mentors)
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

2. Introduction to Flight
Important Terms (your new ‘language’) (Quiz):
Aero
Aerodynamics
Aeronautics
Aerospace
AGL
Air
Aircraft
Airplane
Airfoil
Airport
Altitude
Aviation
Aviator
Camber
Chord
Drag
Dynamic
Leading Edge
Lift
Relative Wind
Static
Supersonic
Thrust
Trailing Edge
Wind
Aerospace Education: ‘the branch of general education concerned with communicating knowledge, skills and attitudes about aerospace activities and the total impact of air and space vehicles upon society’
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

3. Introduction to Flight
Daedalus & Icarus
Greek mythology: Father and son escaped imprisonment by fashioning wings from feathers and beeswax, and flying away
Icarus was said to have flown too close to the sun, which melted the beeswax, and his wings fell apart
Marco Polo
Reported seeing Chinese sailors strapped under huge kites, and used as aerial observers
Montgolfier Brothers
Designed first confirmed manned balloon to actually fly (burner = power)
Flown by d’Rozier and d’Arlandes in Paris France Nov 21st (Note: just 7 years after US declaration of Independence!)
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

4. Introduction to Flight
Daniel Bernoulli ( , Dutch)
When air is accelerated, its pressure drops
Sir Isaac Newton ( , English)
An object at rest will remain at rest unless acted upon by some outside force
THRUST (Propeller or Jet) needed for the plane to move
A force acting upon a body causes it to accelerate in the direction of the force. Acceleration is directly proportional to the mass of the body being accelerated
Prop or Jet causes acceleration, more power = more speed (what would happen if you strapped a jet to a Cessna 172?)
For every action, there is an equal and opposite reaction
Jet points backwards, but plane goes forward
And air impacting under the wing causes the wing to rise
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

5. Introduction to Flight
Bernoulli in action: The Airfoil
Because it has to travel further, the air over the top of the wing ‘travels’ faster, and so is at lower pressure than the air under the wing, and that = LIFT!
This ‘traveling’ air (airflow) is called the Relative Wind
LIFT = CL x R x ½V² x A
CL - Coefficient of lift ~ defined by angle of attack and airfoil design
R - Density of air (mass/volume) ~ more dense = more lift
½V² - ½(Velocity of air)² ~ air speed x2 = lift x4
A - Area of Wing ~ average chord x wing span
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

6. Introduction to Flight
How do the theories of Bernoulli and Newton apply to a bird?
Birds create ‘thrust’ by flapping and controlling the angle of their wings (Dynamic Lift)
They control their feathers to trap air on the downbeat, but allow it through on the upbeat (Newton 1 AND 2)
Also, by tilting the wing upward, Newton’s 3rd law provides additional lift
A bird’s wing has an airfoil like cross-section, so air MUST move faster over than under, which created lower pressure on top = Bernoullian Lift (Induced)
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

7. Introduction to Flight
Four Main Forces acting on an Airplane in Flight:
To stay aloft, Lift MUST = Weight (Mass x Gravity)
To accelerate, Thrust MUST be GREATER than Drag
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

8. Introduction to Flight
How can you get MORE lift from a wing?
Make a Bigger Wing (Area increases {remember lift equation})
(Flaps can do this temporarily)
Increase the Curve of the upper camber (CL increases)
(Flaps also do this temporarily. They provide additional lift at the lower speeds of Take off and Landing)
Increase Speed (½V² increases)
Increase the Angle of Attack (CL increases)
Like when the pilot pulls back on the stick at takeoff
BUT, go too far (over about 17°) and the wing will ‘stall’ i.e. airflow over top of wing separates. A wing stalls at its Critical Angle of Attack
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

9. Introduction to Flight
Airplane Components:
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

10. Introduction to Flight
The Three Axes of an Airplane:
Movement around Lateral Axis = Pitch
caused by Elevator movements
Movement around Vertical Axis = Yaw
caused by Rudder movements
Movement around Longitudinal Axis = Roll
caused by Aileron movements
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

11. Introduction to Flight
So what does a Propeller do, and how?
A Propeller creates thrust that causes the airplane to move forward
It is a wing, on its edge, moving in a fixed circle, creating its own relative wind
Because of its airfoil shape, it creates lower pressure on the forward edge, which results in forward lift, which pulls it (and the attached airplane forward)
Question - how can the propeller create more thrust (lift)?
Aerodynamics of a Propeller (why the funny shape?):
Design tries to equalize the thrust (lift) along the blade
1 = Hub (attachment point, no lift)
2,3,4 = Main Blade (each is faster, so blade gets progressively flatter)
5 = Tip (fastest point, so lowest curve)
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

12. To Fly by the lifting power of rising air
Important Terms:
Soaring
staying up on natural energy
Span
distance between wingtips
Spoilers
wing lift reducers (Dive Brakes)
Stability
atmosphere resistance to vertical motion
Thermal
rising column of air
Tow Plane
plane providing initial thrust and altitude ‘gift’ for a glider
Wave
up and down air currents from air flow over mountains
Altitude
AGL or MSL
Aspect Ratio
Wing Span : Chord
Convection
Fluid motion due to temp differences
Density
Mass/Volume
Glide Ratio
How far forward per unit of descent
Lapse Rate
temp decrease / altitude increase
Lift-to drag Ratio
gliding efficiency
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

13. To Fly by the lifting power of rising air
How rising air provides LIFT for flight:
Heat from the sun (93 Million Miles away!), causes air to warm up and rise
Heated air rises because it becomes less dense (molecules move more, and push each other further apart), and so this air is now lighter than surrounding air
The upper atmosphere is quite cold, so eventually this rising air cools, and falls again
The rising and falling motion is called convection
When the atmosphere resists convection, it is said to be stable
Cooling with altitude is called the Lapse Rate, which is about 3½°F for every 1000ft up
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

14. To Fly by the lifting power of rising air
Gliders and Sailplanes
Sailplanes can ride the columns of warm rising air, and stay aloft by soaring on the free solar energy
Gliders do not soar, but they do have a higher glide ratio than conventional powered airplanes
Both Gliders and Sailplanes must first be towed to altitude
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

15. Balloons - They create their own thermals
Important Terms:
Balloon - Aircraft lifted by lighter than air gas, with no means of horizontal control
Burner - Device which heats air (hot air is lighter than surrounding air)
Buoyancy - Rising or Floating in a fluid (such as air or water)
Crown - Top of a Balloon’s ‘Envelope’
Envelope - The main body of a balloon (usually nylon)
Gore - The vertical panels that make up the envelope
Montgolfier - French brothers who created first successful manned balloon
Parachute Panel - Device inside top of envelope, allows hot air to escape when required
Propane - Lightweight fuel for burner
Thermistor - Device which measures temp inside envelope
Variometer - Vertical Velocity Indicator (Rate of Climb/Descent)
Wicker - Woven wood used to make the basket (Gondola)
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

16. Balloons - They create their own thermals
How a Balloon flies:
Buoyancy - Hot Air is Lighter than Cold air, so it rises above it
Trap enough hot air inside the envelope, and the buoyancy can lift both the air itself, and the balloon and passengers too
To Rise - The envelope’s air is heated by the Propane Burner
To Descend - Hot air can be ‘let out’ through a vent at the top of the envelope by partially collapsing the Parachute
Directional control comes from natural wind, which moves in different directions at different altitudes - So the pilot must climb/descend to find a wind going in the required direction
The Math of a Balloon’s Lift:
Hydrogen balloon (like the Hindenburg) ~ 60lb LIFT per 1,000 cu ft
Hot Air balloon ~ lb LIFT per 1,000 cu ft
77,000 cu ft balloon LIFT = 17 x 77 = 1309lb ( minus about 600lb for envelope + basket, burner and propane = 709lb payload )
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

17. Balloons - They create their own thermals
Balloon Components
( feet wide)
Load Tapes support the envelope, and maintain its shape (ideally spherical)
Typical Instruments are Thermistor, Variometer (Vertical Velocity Indicator), and Altimeter
Typical materials are Nylon & Dacron, with a Polyurethane coating
Several MILLION BTU’s per Hour (1 BTU = raise 1 lb water by 1°F)
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing

18. Balloons - They create their own thermals
Hydrogen balloon example (not for test)
Hindenburg the Largest Aircraft EVER to Fly
Gas volume 7,062,000 cubic feet!!
LIFT = 60 x 7062 = 423,720lb (212 TONS!! Actually quoted as 242 Tons)
Minus about 260,000lb for structure and fuel = 112 Tons useful payload!!
That’s the Gross Weight of a Boeing !
Only 9% shorter than the Titanic!
She was destroyed by fire while arriving at NAS Lakehurst NJ, May 6, 1937
Now known that fire was due to flammable skin NOT Hydrogen
Dr. R.A. Bartholomew Civil Air Patrol, New Jersey Wing