1. The Early Days of Flight
Overview & Objectives
Know developments of “Lighter-than-air” craft from Leonardo da Vinci to Wright brothers
Know ways balloons were used in US Civil War
& Spanish-American War
Know developments of “Heavier-than-air” from Leonardo da Vinci to Wright brothers
Chapter 1, Lesson 2

2. Problems to Overcome How to get up in the air
How to stay up in the air
How to control where they are going once in the air

3. Developments in “Lighter-Than-Air” Flight
Balloons
How do they work?
If air or gas inside a balloon is lighter
than the air around it, it will float
- Principle of:
Hot air takes care of the first challenge of flight:
getting up into the air
Buoyancy
Chapter 1, Lesson 2
Taken from wikipedia.com

4. Hot Air Balloons Laurenço de Gusmão - a Jesuit priest
Credit for inventing the hot-air balloon
In 1709, demonstrated it to King of Portugal
Chapter 1, Lesson 2

5. The Montgolfier Brothers
Joseph & Étienne Montgolfier
First balloon flight w/ humans aboard
Lit a fire in fireplace
Held open a small silk bag over fire
Bag swelled & rose to the ceiling
New gas? Observed a principle of physics:
Hotter air rises above cooler air
Chapter 1, Lesson 2

6. The Montgolfier Brothers
French King Louis XVI & his Queen, Marie Antoinette, asked to see it
Eventually, led to first manned balloon flight, on 21 Nov 1783
How to keep it up? (2nd challenge)
Keep balloon hot – problems?
Dangerous
Fuel is heavy
Chapter 1, Lesson 2

7. Balloons & Lift
Meanwhile, young scientist J. A. C. Charles experimented with hydrogen
Lighter than air gas
Provided much more lift than hot air
Lift - Upward force on an aircraft against
gravity
Benefits of hydrogen?
Didn’t need to carry fire or fuel aloft
Chapter 1, Lesson 2

8. Hydrogen Balloons Risks of Hydrogen ? Very flammable
Hindenburg
Risks of Hydrogen ?
Very flammable
Many people were killed before started using Helium (a safer gas)
Charles & a passenger made the first manned hydrogen balloon flight on 1 Dec 1783
Lasted more than 2 hours, flew over 27 miles
Chapter 1, Lesson 2

9. Military Use Benjamin Franklin saw one of Charles’s balloons in 1783
Immediately wrote home, stressing the military importance of the balloon
In 1793, French Army started using balloons for aerial reconnaissance
Looking over battlefields from the sky
Chapter 1, Lesson 2

10. Dirigibles Control The Dirigible
Still needed to solve the 3rd problem of flight:
Control
Eventually, inventors designed a steerable airship
The Dirigible
Chapter 1, Lesson 2

11. Dirigibles These new airships had 2 things that helped pilots steer:
Rudders
Movable surface attached to the rear
Turns the craft left or right
Power sources / propellers
Now airships could move through the air much as sea ships move through water
Chapter 1, Lesson 2

12. First Dirigible In 1852, Henri Giffard of France built first
cigar-shaped dirigible
3-horsepower steam engine pushed it through the sky at about 5 mph
Chapter 1, Lesson 2

13. Dirigible Improvements
Alberto Santos-Dumont
Santos-Dumont’s built 82 feet long
NONRIGID airship
3-horsepower gas motor
Reached altitude of 1,300 feet
Steered w/ rudder
Flew 14 of these dirigibles
In 1901, around the Eiffel Tower
Won a big cash prize
Sparked interest in aviation
worldwide
Chapter 1, Lesson 2

14. Count von Zeppelin July 1900, a German inventor built & flew….
First RIGID dirigible - the LZ-1
Led to world’s first commercial airships
The Zeppelins were luxurious:
Roomy, wood-paneled cabins for over 20 passengers
Flew at speeds over 40 mph

15. Aeronauts Aeronaut - people who travel in airships or balloons
One named Thaddeus Lowe tried to interest
Gen Winfield Scott—head of Union Army—in balloons
Scott saw no military need for balloons
But Lowe didn’t give up
Eventually, he convinced President
Lincoln w/ a demonstration
Lowe was finally allowed to organize
a Balloon Corps of the Union Army

16. Balloons & Battle of San Juan Hill
1898, US at war w/ Spain…
Battle of San Juan Hill proved to
Army what balloons could do!
Lt Col George M. Derby moved
Army’s only spy balloon close to action
From there, observers in the balloon could see a new trail leading to the Spanish forces
US commanders then divided soldiers into 2 forces to advance a/g Spain

17. Battle of San Juan Hill
The balloon observers also directed artillery fire from El Pozo Hill a/g San Juan Hill trenches
Historians say this led
to the US’s victory

18. Gliders – “Heavier than Air Flight”
George Cayley
John Stringfellow
Otto Lilienthal
Sam Langley

19. Sir George Cayley 1850 built first successful full-size manned glider
Englishman
Used Leonardo da Vinci’s glider ideas
His glider designs are like today’s
Wings in front, tail in back
Radical “Fixed wing” designs
Separate system for propulsion
Identified 3 aviation forces:
Lift
Drag
Thrust
1850 built first successful full-size manned glider

20. John Stringfellow 1843, Patented the “Ariel” glider
that theoretically could carry a man
Steam engine drove 2 propellers
Never actually built
But 1848, Stringfellow did build
a steam-driven model that did fly
1st successful powered flight
of a “heavier-than-air” craft

21. Otto Lilienthal “Father of Modern Aviation”
German
Learn to fly “by flying”
>2000 glides

22. Otto Lilienthal Also designed powered Biplane - Double wing plane
On eve of the test flight of
his biplane, he decided to
fly his glider one more time
It stalled 50 feet up
& he fell to his death
- Double wing plane

23. Sam Langley Knew that power was key
1st to try to build flying machine w/ motor
Strong political figure
Received $50,000 grant
“The Aerodrome”
Built 9 models
One flew ¾ mile
Never succeeded in gaining control

24. Samuel Langley Engine worked well, but on takeoff
it caught on the launch car
& fell into river
Gov’t withdrew support, so Langley gave up
Historians fault Langley
for focusing:
Too much on power
Too little on control
Even so, for his contributions to aviation,
Langley Air Force Base in VA is named after him