General BAK Theory Flashcards
Stability
Positive - returns to original state
Neutral - Continues new course, doesn’t diverge further
Unstable - Deviates further from the mean
Lateral Axis
Pitch around it, elevators
longitudinal Axis
Roll around it, Ailerons
Normal Axis
Yaw, Rudder
Frise Ailerons
Leading edge tucks in on down going aileron but petrudes into airflow on upgoing aileron, causing drag to help compensate for adverse yaw
Differential Ailerons
Up going aileron deflects further into airstream than down going, increased drag to minimise adverse yaw
Types of Drag
Induced - resultant of lift generation
Parasite Drag - Form, Skin Friction and Interference
Induced Reduces with increase IAS
Parasite increases with increase IAS
PUDSUC
Pitot Blocked - IAS under read on Descent,
Static Blocked - IAS under read on climb.
VHF Range
Below 5000’ = 60 nm
Between 5000’ - 10,000’ = 90 nm
Between 10,000 - 15’000 = 120 nm
VHF
30MHz - 300 MHz
Very High Freq
Line of sight
HF
3MHz - 30MHz
High Freq
Tends to follow curvature of the earth
Angle Of Attack
Angle between Chordline Line and relative airflow
Chordline
Straight line from leading edge and trailing edge of aerofoil
Mean camber
Line that is equidistant upper and lower aerofoil surfaces
4 Stroke engine
Suck / Squeeze / Bang / Blow
Pre Ignition
Mixture ignites before spark plug
Cylinder Hot Spot, contamination High power lean mixture
Rough running, possible back fire, sudden increase CHT
Detonation
Air/Fuel mix gets to hot and spontaneously combusts prior to TDC (against rising Cylinder head)
Incorrect fuel usage (below 100 octane rating) - resistance to compression
Engine Oil - 5 uses
Lubricate - reduced friction Cool - carries heat away Clean - carries contaminants away Seal - Protect - Coats surface and reduce exposure to air/corrosion
Bernoulli’s Theorm
Px Total = Px Dynamic + Px Static
If Px Total doesn’t change so if Dynamic Px is increased (Air speed) static PX is reduced
See Wing Lift and Carby
Venturi
Pinched tube, air accelerates through narrowest point thus reducing the static pressure
Carby throat / butterfly
ISA
OAT 15
ELR 2Deg / 1000’
QHN 1013.2 HP
Lift Formula
L=Cl 1/2 Rho V2 S
L = IAS x AoA
Best Lift drag Ratio
Best range
Bottom of the drag curve, tangent of Power curve
Least drag, NOT the Most LIFT
Endurance
Time / Rate
Least Power required - lowest fuel burn
Holding pattern
Generally less than Min Drag
SPEEDS
I C E T
Pretty Cool Drink
Indicated - Calibrated - Equivalent - True
Position Compression Density
Vx
Best angle
Excess Thrust
Effected by wind
Vy
Best rate (Rate always relates to time/work done)
Excess power
Not effected by wind
Service Ceiling
Climb rate 100’/min
Absolute Ceiling
No further climbing possible
Impulse Coupling
Retards the spark on ignition
Creates stronger spark at correct timing
Winds up a spring which then releases to create stronger spark
Centre Zero Ammeter
ALT - BUS - Ammeter - BATT
Cessna - Flows to the battery (+) or from the battery
(-)
Should be slightly (+), could be high initially to recharge battery
Left Zero Ammeter
Load Meter
ALT - Ammeter - BUS - BATT
Piper - Flow from the Alternator
Should be slightly (+), IF Zero system being powered/load carried by battery
Gyroscopic precession
As gyro spin will drift slightly in space due mechanical imperfections - bearing friction etc
Heading on DG every 15-20 mins
Gyroscopic Instruments
Faster they spin, heavier they are the better the Rigidity - tendency to hold their alignment
PA Calc
PA = Height + (1013 - QNH) x 30
Reasonable man, If QNH below ISA, PA must be higher, inverse relationship
DA Calc
ISA Deviation = 15 - (PA/1000 x 2)
Temp Correction = OAT - ISA Dev …. x 120
DA = PA + Temp Correction
Reasonable man If OAT is higher than ISA, DA is higher
Altimeter Faults
Static block - will display Alt at which blockage occurred
Incorrect Datum (QNH) set =
Underset - Under read, A/C higher than indicated
Overset - Overread, A/C is LOWER than indicated
Travelling High To Low Lookout Below, you will be lower than you read/believe
Altimeter Tolerance
VFR +/- 100’, ( can be 110’ for elevation above 3300’)
Source within 100nm
Known elevation can give local QNH (Question Nil Hgt)
Setting Zero on Altimeter give QFE (Question Field Elevation)
Magnetic Variation
Variation from True North
Isogonals lines on map joining place of equal value
East is Least (-) from True to get Mag
West is Best (+) Add to True to get Mag
Magnetic Deviation
Compass Error caused by electrical system, airframe etc
Placarded within the A/C on deviation card
Compass Turns - ONUS
Overshoot North, turn through your desired heading & compass will come back when you roll wings level
Undershoot South, rollout early and compass will continue after you roll out
Compass turns - SAND
Acceleration error east - west
Accelerate indicates turn Sth
Decelerate indicates turn Nth
VMC - Class C
5 km vis (8 km above 10,000’)
1000’ Above/below
1500m Horizontal
VMC Class E
5 km vis, (8 km above 10,000’)
1000’ Above/below
1500m Horizontal
IFR require clearance / VFR not required
VMC Class D
5 Km Vis
1000’ above, 500’ below
600m Horizontal
Special VFR
1.6 Km Vis
Clear of cloud
CAR 157 Limits apply
VMC Class G below 3000’ or 1000’ AGL
5 km Vis,
Clear of cloud in sight of land /water
VMC Class G Above 3000’
5 km vis, (8 km above 10,000’)
1000’ Above/below
1500m Horizontal
Minimum Height Rules
Populated Area - 91.265
Non Populated Areas - 91.267
Not below 1000’ above within 600m radius of populated areas
Not below 500’ above within 300 m radius of non populated areas
except due stress of weather??
Last Light
Must plan to land atleast 10 prior last light, or in accordance with company regs
