What is Cramer's Rule

(practice problems)

What is sheer stress and tangential stress

tangential stress is when a force acts at an angle to the surface

Sheer stress is when a force acts parallel to the surface

Sheer stress is always tangential stress, but not all tangential stress is sheer stress

What are the four fundamental quantities of a fluid

Pressure, Density, Temperature, Velocity

A fluid is a substance which ______________________.

Cannot resist an applied sheer stress

What are the two types of fluids

Incompressible (liquid) and Compressible

Define Pressure

The normal force per unit area

P=F/A

Units: N/m^2, lb/ft^2

Define Density

Mass per unit volume

p=m/V

units: kg/m^3, slug/ft^3, lbm/ft^3

Define Temperature

average Kinetic Energy of the particles in a gas

KE=(3/2)kT where k is the Botlzmann constant (k=1.38 * 10^-23 J/K)

Units: K, C, R, F

when the flow is steady, the moving elements make fixed paths in space called ____________.

streamlines

What is a flow field?

(search this up later)

What is a perfect/ideal gas?

one which the intermolecular forces are negligible and where particles are widely separated (low density)

What is the equation of state?

P=pRT

R is the specific gas constant

What is specific volume?

The volume per unit mass. It is the inverse of density

What is this plane and what is it known for?

Convair B-58 Hustler

First supersonic strategic bomber capable of Mach 2 flight

Delta wing

what type of flow has a constant velocity that does not change or fluctuate with time?

A steady flow

What do you call the path taken by a moving fluid element

a streamline

What are the two aerodynamic forces?

Lift and Drag

The aerodynamic force exerted by the airflow on a surface stem from two sources:

1. Pressure Distribution on the surface

2. Shear stress (friction) distribution on the surface

What is shear stress?

the force per unit area acting tangentially (parallel) on a surface due to friction

tangential force times the surface area

What are the two types of payload?

Fixed payload (passengers, cargo, etc)

drop payload (skydivers, water, dust)

What happens when the pressure below the wing is greater than the pressure above the wing

Lift! The lift coefficient equation is C_L = L / q(bar) S where q(bar) is called the dynamic pressure, and it is given by q(bar) = (1/2)pv^2 (v is the free stream velocity)

Where does lift come from?

Lift occurs when a moving flow of fluid is turned by a solid object. The flow is turned in one direction and lift is generated in the opposite direction.

if there is no motion or no fluid, then there is no lift.

what is the difference between wind tunneling and actual flight?

Wind tunneling is when the headwinds are equal to the thrust, so the plane's speed relative to the ground is zero.

When the plane is moving relative to the ground, it is called actual flight

What are the three moves an airplane can make?

Pitch (up and down)

Roll (rolling around)

Yaw (left and right)

What is A?

Fuselage: Carries people, cargo, payload

What is G?

Vertical Stabilizer: yaw stability

What is F?

Rudder: provides yaw control (left and right motion)

What is E?

Horizontal Stabilizer: pitch stability (up and down)

H-stab, H tail

What is the combination of E, F and G called?

Empennage

What is D?

Main Landing Gear: supports aircraft weight on the ground (tricycle landing gear configuration)

What is c?

Nacelle: outer covering that encloses engine

What is B?

Nose Gear: Ground steering

What is H?

Wings: provide lift

What is I?

Aileron: provides roll control (left or right) (they are opposite of each other)

What is J?

Elevators: pitch control (up and down)

What is K?

Spoiler: Reduces lift and increases drag (independent movement of each other)

What is L?

Winglet: reduces drag (wing vortex control)

What is M?

Slat: aids in takeoffs and landings (increases or decreases wing surface area)

What is the longitudinal axis called and what causes the movement along it?

The roll axis: controlled by the yoke (turn the yoke left or right to turn the ailerons up and down)

Ailerons cause the movement by going up or down (located at the ends of the wings)

What is the lateral axis called and what causes the movement along it?

The pitch axis: controlled by pushing the yoke in to dive down and pulling them up to pitch up.

The elevators control the pitch by simultaneously flapping up or down

What is the vertical axis called and what causes the movement along it?

The yaw axis: causes the aircraft to spin left or right by pushing the right or left rudder pedal.

The rudder controls this movement by deflecting the airflow right or left from its position on the tail. Kind of like a shark tail.

What is the manufacturer, designation, and name of this aircraft?

The Consolidated B-24 Liberator

- world's most produced bomber (rapid production because of WW2)

- Called the flying coffin because there was only one exit, so the pilot couldn't escape

- straight (davis) wing, twin tail

what are airplanes with 1, 2 and 3 wings called?

Monoplane (Fairchild Republic A-10), Biplane (Boeing Stearman), triplane (Fokker Dr. I)

What is the name of this aircraft?

Fairchild Republic A-10 Thunderbolt

- AKA A-10 Warthog

-designed to provide close air support (CAS) to ground troops

-the only production-built aircraft designed solely for CAS

What is the name of this aircraft?

Boeing-Stearman Model 75

- military trainer aircraft

- after WW2, they were sold on the civilian market and were used for crop dusting, racing, and wing walking

What is the name of this aircraft?

Fokker Dr. I Red Baron

- WW1 fighter aircraft

What locations can the wings be placed in?

High wing (cessna 172), mid wing (f-16), low wing (Piper cherokee)

What is the name of this aircraft?

Cessna 172 Skyhawk

- more of these were built than any other aircraft

-most successful aircraft in history

What is the name of this aircraft?

General Dynamics (aka lockheed martin) F-16 Fighting Falcon

- world's most common fixed wing aircraft in the military

What is the name of this aircraft?

Piper Cherokee

- designed for flight training, taxi and personal use

- 4th most produced aircraft in history

What is the name of this aircraft?

Boeing 787 Dreamliner

- swept back wings

What are some other types of wings?

Swept back wings (boeing 787), swept forward wings (Grumman X-29A), canard at the front (Piaggio Avanti P180)

What is the name of this aircraft?

Northrop A-9A

-prototype that was passed up for the Fairchild A-10

What is the lift equation?

L = (1/2)pv^2SC_L

or

L = q(bar) S C_L

What is the dynamic pressure formula?

q(bar) = (1/2)pv^2

What are the atmospheric layers (starting from bottom to top) and how does this affect atmospheric conditions?

(troposphere, tropopause, stratosphere, stratopause, Mesosphere, mesopause, Thermosphere)

At the "spheres", temp changes linearly with altitude

at the "pauses", temp is constant

Hydrostatic equation

dP= -pgdhg

What is the geometric altitude

h_g, the geometric height above sea level is

what is the absolute altitude?

h_a the height measured from the center of the earth

What is the equation for the absolute altitude?

h_a = h_g +r (radius of the earth)