# Preflight Ground School Unit 1

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PREFLIGHT GROUND SCHOOL UNIT 1
Important times
Books you will need
Preflight handbook
Big Bend Bible – Training Course Outline (TCO) Must be carried in the plane
Airplane Flying Handbook FAA-H_8083-3
Logbook (Must be carried on all solo flights)
B-19 Flight Manual

Aerodynamics
The 4 forces:
Lift
Weight
Drag
Thrust

Lift
Bernoulli’s Principle – the higher the velocity the less pressure on that surface
Newton’s 3rd law – for every action there is an equal and opposite reaction
This explains why downwash and deflection are also ways lift is created.
Lift On An Airfoil

Definitions
Camber – curvature of the wing
Chord line – straight line from leading to trailing edge
Relative wind – wind as it travels over the wing

Definitions
Angle of Attack – angle between chord and relative wind
Critical angle of attack – where stall occurs
Weight
Gravitational force exerted by the earth
We have 1g acting on us right now

Drag
Resistance of the air particles striking and flowing around the airplane
1. Parasite drag – resistance to skin friction
2. Induced drag – result of lift

Thrust
Generated by propeller
Fixed pitch prop vs variable pitch prop
Rotating wing
Primary Flight Controls
Ailerons control bank and are located on the outboard trailing edge of the wing
Rudder controls yaw and is located on the trailing edge of the vertical stabilizer
Elevator/Stabilator controls pitch is located on the trailing edge of the horizontal stabilizer or empenage

Axis of Control
Longitudinal axis runs nose to tail
Ailerons control bank about the longitudinal axis
Vertical axis runs through the roof and belly usually through the cabin area
Rudder controls yaw about the vertical axis
Lateral axis runs wingtip to wingtip
Elevator controls pitch about the lateral axis

Secondary Flight Controls
Trim tabs
Fixed trim tabs
Other more exotic include:
Servo tabs
Balance tabs

Secondary Flight Controls
Flaps increase lift and increase drag
Flaps change the camber allowing more lift to be generated
Flaps allow a steeper angle of descent and a slower approach speed
Located inboard trailing edge of the wing
4 types:
Plain, Split, Slotted, and Fowler

Ground Operations
High percentage of accidents happen here
Look for the flashing beacon
Yell clear before turning prop with starter
Be alert when walking on the ramp
Have a wing walker on each wing
Make sure magneto switch is in off position before attaching tow bar

Ground Operations
The checklist
Do not memorize
However be very familiar with it
Use it as an aid

Ground Operations
The Propeller
Make sure magneto switch is off first
Grab prop at the hub to push or pull the aircraft

Ground Operations
Rudders/Brakes
On the same peddle
Brakes on top, Rudder on the bottom
Use brakes for stopping only
Do not use to turn
Do not use heavily after landing
Brake failure – loss of fluid, leaky master cylinder, air in the lines

Documents
A – Airworthiness Certificate
R – Registration Federal and State
O – Operating Limitations
W – Weight and Balance
Be careful: Logbooks are not required, State registration not required (by the feds), Radio station license not required

Fuel Diagram
Be able to reproduce this diagram from memory

Powerplant
Turn to Page 17
4 cycle, 5 event
Intake
Compression
Ignition
Power
Exhaust

Powerplant
Carburetor heat – melts ice in intake system
The proper procedure for detecting and melting carb ice
1. Note carb ice – RPM drop
2. Pull carb heat full on
3. Note RPM drop as ice melts
4. RPM increase to higher or original RPM

Powerplant
Engine Instruments:
1. Oil Temp 60°-120° F yellow, 120°-245° F Green, 245° F Red Line
2. Oil Pressure 25-60 psi yellow, 60-90 psi green, 100 psi Red Line
3. Tachometer 1800-2700 green, 2700 rpm Red Line

Powerplant
Instruments:
4. Fuel Quantity – Yellow indicates less than 11 gallons
Take off with fuel in yellow arc is prohibited
5. Fuel Pressure – .5-6 psi green
Magneto Switch

Powerplant
Magneto generates electrical impulse to fire the sparkplugs
There are 2 on each engine
Each drives 4 sparkplugs
Totally separate and independent of the electrical system
As long as the engine turns and the key is on they will fire

Powerplant
1. Increased safety
2. More complete and even combustion
3. Higher performance

Powerplant
Guide to engine leaning and when
Only special times usually on x-c’s
Leaning should take place at higher altitudes, anytime less dense air exists
Do not lean on takeoff
Lean until RPM peaks and then drops
Enrichen until it peaks again
Enrichen a little more to ensure rich side of peak

Powerplant
Function and operation of:
1. Throttle
2. Mixture
3. Mag Switch
4. Starter Switch
5. Battery Switch
6. Alternator Switch
7. Circuit Breakers

Systems
Location of Battery
Ammeter
Systems
Oil sump
8 quarts max
6 quarts min
SAE weight and type on oil door

Systems
Fuel Tanks
52 gallons useable
80-87 octane minimum
100-130 green

Instruments
Basic T arrangement
Airspeed indicator hooked to pitot tube and static ports
Measures the difference between ram pressure and static pressure
Airspeed Indicator

Altimeter
Big hand = hundreds
Medium hand = thousands
Little hand = ten thousands
Hooked right into the static ports

Vertical Speed Indicator
Feet per minute up or down
Hooked into static ports
6 to 8 second lag time for rate information
As a trend instrument it gives immediate information

Vacuum Instruments
Attitude indicator (Gyro)
Instrument air gauge 4.3-5.9 inches of Hg green arc

Emergencies
Low oil pressure or High oil temp
1. Adjust power to maintain 78 kts
2. Continue powered flight to nearest suitable landing place
3. If engine failure is imminent, plan a landing while engine power is still available

Emergencies
Ammeter charging full scale (probably a bad regulator)
1. Turn off alternator switch
2. Turn off all nonessential electrical stuff

Emergencies
Backfire and black smoke on startup
probably over primed (flooded)
Use flooded start procedure
Beware of fire risk

Emergencies
Loss of power for no apparent reason
probably carb ice
Use carb heat

Emergencies
Battery failure
Caused by electrical charging failure
Loss of radios, fuel gauges, oil temp, stall horn, turn coordinator

Emergencies
Alternator failure
indicated by discharge or fluctuating ammeter
Alt switch off
All nonessential electrical off to conserve battery

Emergencies
Acid Smell
usually overcharge or cracked battery
May have suffered jolt or freezing
Alt switch off
All nonessential electrical off to conserve battery

Airspeeds to Remember
Vy 72 kts– Best rate of climb
Vx 65 kts– Best angle of climb
Stall 50 kts flaps down
Stall 59 kts flaps up
Best Glide 78 kts

Other
Max gross weight Normal category 2150
Max gross weight Acrobatic and Utility category 2030