Transcript Aerospace Engineering

Pre-Class Friday
10-5-12
What do you think Aerospace
Engineers do?
Pre-Class Monday 10-8-12
During a recent inter-school athletics event,
four girls competed in the 10 km race. Jane
Brown beat Lucy. Miss Guest beat Lynne.
Anne was not third. Miss Joseph was not
last. Miss Scott, who was not Anne, came
just after Jane. Can you tell which girl came
where?
1. Anne Guest
2. Lynne Joseph
3. Jane Brown
4. Lucy Scott
Aerospace Engineering
Improving life on Earth by
changing how we fly above it
Aerospace Engineers
 Design, develop, test, and help manufacture
aircraft, missiles, rockets, and spacecraft
 Develop new technologies for military or
commercial use
 Supervise the manufacturing of products
 Starting salary in 2010: $58,080; with
average salary in 2006: $87,610
 Divided into two basic fields
– Aeronautical: aircraft
– Astronautical: spacecraft
Aeronautical
 Develop technology for use in aviation,
defense systems, and attack projectile
weaponry
 Specialize in structural design, guidance,
navigation and control systems, and
instrumentation and communication, as it
applies to both civilian (commercial) and
military products
 Other areas of knowledge are:
aerodynamics, thermodynamics, celestial
mechanics, propulsion, and acoustics
Paper Winglets
 Objective
– To test the design of a paper airplane with and
without winglets.
 Materials
– Student sheets
– Rulers
― Copy paper
― Cardstock
 Procedures
– Read the Background Information.
– Follow the Procedures on student sheets.
– Write on the ”tabled” page only.
Pre-Class Tuesday
10-9-12
Which of the four black shapes
is identical to the red one?
The 4 Basic Forces of Flight
 Lift
 Thrust
 Gravity
 Drag
When an aircraft is
flying level at a
constant speed, all
four of these forces
are in balance or
equilibrium.
 Since air density and the acceleration of gravity
changes with the height above the planet’s surface, all
of these forces are affected by one thing: altitude. At
higher altitudes, the air is thinner, while at lower
altitudes the air is thicker. This change in the
properties of air will affect how well the engine and
wings work.
 The pilot only has the ability to directly affect three of
these forces.
The Forces of Flight
 Lift is achieved through the crosssectional shape of the wing
(airfoil).
 As the wing moves through the air,
– the wing's shape causes the air
moving over the wing to travel
faster than the air moving under
the wing
– the slower airflow beneath the wing
generates more pressure, while the
faster airflow above generates less
(Bernoulli’s Principle)
– this difference in pressure results
in lift
 Lift will vary dynamically
depending on the speed an aircraft
is traveling at.
 Another factor to lift: Angle of
Attack (AoA)
– The angle at which the airfoil meets
the airflow
– The angle of the wing relative to
airflow
Lift
Go Fly A Brick
 Objective
– Simulate the landing of the Space Shuttle
 Materials
– Shoebox
– Cardstock (2)
– Scissors
– Tape
 Procedures
– Follow the instructions on the lab paper
– Be sure to answer the questions
– Do not damage the shoebox!
– Finish by the end of class
Fill-in the Chart
Pre-Class Wednesday
10-10-12
There are _____
forces of flight.
Drag
 The force on an aircraft, as it is propelled
through the air, that resists its motion
due to the air flowing over the aircraft
(causing friction)
 Can be increased or decreased
depending on the size, shape, and cargo
of the aircraft
 The maximum speed
that can be obtained
by a falling object
 The force of gravity is
equally balanced by
the air resistance force
(drag)
 Constant speed, no
acceleration
Thrust
 The force generated by the air in front of the
aircraft being pulled by the propeller or turbine
of the engine and pushed back towards the tail
 Gives the aircraft forward velocity, which
creates lift on the wings
 In general, the greater the thrust, the greater
the airspeed
 Controlled by the throttle, which raises or
lowers the revolutions-per-minute (rpm) of the
engine
Air Power




Follow the instructions on the paper.
Use a meter stick rather than a ruler.
One balloon and one straw per group
Replace question #3 with: “Find the maximum
velocity of your air engine (balloon).”
Pre-Class Thursday 10-11-12
If a plane is attempting to fly
through a thinner atmosphere,
what happens to the lift?
Effects from Thrust and Drag
 Doppler Effect
– The change in frequency of a wave due to the
motion of the source or receiver
– http://www.kettering.edu/~drussell/Demos/doppler/doppler.html
 Sonic Boom
– Damaging to anything in its path
– Could be cool to watch:
http://www.youtube.com/watch?v=wHrwgRsX0BI
– http://www.youtube.com/watch?v=GsKwrN0AimE
ACCELERATION BY GRAVITY
 The Earth constantly
accelerates all objects
towards its center
 We use the variable g
for the acceleration of
gravity
 g = 9.8 m/s2
 a = - g = - 9.8 m/s2
WEIGHT
• Recall: a force is a push or pull on an object
• The force of gravity, a.k.a. weight, is the attraction of
any object (with mass) towards the center of the Earth
W=m g
W : weight in Newtons (N) or pounds (lb)
m : mass in kilograms (kg) or slugs
g : acceleration of gravity (9.8 m/s2 or 32 ft/s2)
FALLING LAB
 Materials:
– 6 pennies
– stop watch
– meter stick
– tape
 Objective:
– Determine the acceleration of gravity
 Each group will turn a paper into me
today.
PROCEDURES
 Stack five pennies and tape them
together.
 Drop the five pennies 3 different times.
 Measure the distance fallen and the
time it took to fall to the ground.
 Determine the acceleration of gravity.
 Repeat the experiment for the single
penny.
 Complete the chart on the next slide
and answer the questions.
FILL OUT THE CHART
DROP
d (m)
t (s)
2
a (m/s )
1
2
3
1
2
3
How could you improve your results (at least 2 examples)?
Pre-Class Friday 10-12-12
Due to the aerodynamics of the Space Shuttle,
it is often called a _____.
a.
b.
Flying brick
Monument of engineering
c. Paper rocket
d. Weightless wonder
Above and Beyond Activity
Astronautical
 Develop technology for use in space
exploration
 Specialize in propulsion, guidance and
control systems, structural design, and
defense systems
 Like aeronautical, safety is a premium…
people’s lives are depending on your work
Pre-class Monday 10-15-12
 There are two possible answers to the
following problem:
What is half of two plus two?
 Give me both of them.
Pre-Class Monday 3-5-12
In spacecraft design, list three
things you need to know
before you begin your plan.
Pre-Class Tuesday 3-6-12
Write:
“Guest Speaker: Matthew Hitt,
UAHuntsville Aerospace Engineer.”
Pre-Class Wednesday
3-7-12
Assume the performance test
was challenging, what was the
biggest challenge in it? Explain.
Pre-Class Thursday 3-8-12
What is the name (acronym) of
the professional organization for
Aerospace Engineers?
Pre-Class Friday
10-5-11
Which of the seven black shapes are
identical to the red one?
Pre-Class Tuesday
3+8=11
Write: “Continuing
Performance Test.”
Pre-Class Friday 10-1-10
 Today’s date is a binary number
(10110). What is the decimal
(base 10 number)?
 Remember: there are 10 kinds
of people in the world: those
who understand binary and
those who don’t.
Pre-class Wednesday
2-29-11
All months have 30-31 days, except for
February which has a changing number of
days. Explain why today is the last day of the
month and not yesterday.
Believe it or not, it was designed this way.
Designing a Leap Year
 The next leap year will occur in 2016.
 In the Gregorian calendar the following three criteria
must be met to be a leap year:
– It is evenly divisible by four;
– If it can be evenly divided by 100, it is NOT a leap year, unless;
– The year is evenly divisible by 400. Then it is a leap year.
 This means that years 1800, 1900, 2100, 2200, 2300
and 2500 are NOT leap years, while year 2000 and
2400 are leap years.
 In the Julian calendar–there was only one rule: any
year evenly divisible by four would be a leap year. This
calendar was used before the Gregorian calendar was
adopted.