CAAB PPL Theory flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Transition altitude

The altitude at or below which the altimeter is set to the local QNH; above it, pilots set 1013.25 hPa and fly flight levels.

Right-of-way order

In the air, balloons have priority over gliders, gliders over airships, and airships over powered aircraft; aircraft in distress always have priority.

VMC minima Class C-E

At or above 3050 m AMSL, flight visibility must be 8 km with 1500 m horizontal and 300 m vertical cloud clearance.

Four-stroke cycle

Induction, compression, power and exhaust strokes complete one cycle in two crankshaft revolutions; the power stroke is the only one producing work.

Carburettor icing risk

Most likely with outside air temperatures between 0 and 15 °C and high humidity; apply carburettor heat before reducing power to prevent ice build-up.

Magnetos

Engine-driven, independent ignition sources; one failure causes slight power loss and higher exhaust gas temperature, while both failing stops ignition.

Density altitude

Pressure altitude corrected for temperature; it equals pressure altitude plus 120 ft for each degree Celsius above standard temperature.

Centre of gravity moment

Moment equals mass multiplied by arm; total moment divided by total mass gives the centre of gravity position in the aircraft.

Headwind effect on take-off

A headwind reduces ground roll and take-off distance; a tailwind increases it by about 10 percent for each 2 knots.

Hypoxia onset

Symptoms may appear near 10 000 ft in unacclimatised pilots; time of useful consciousness at 25 000 ft is only about 3 to 5 minutes.

Spatial disorientation

False sensations of attitude from the inner ear; pilots must trust instruments rather than sensations, especially in cloud or at night.

Alcohol and flying

Allow at least 8 hours between last drink and flight, and 24 hours after heavy drinking; blood alcohol must be zero.

QNH and QFE

QNH is pressure reduced to sea level for altimeter reading; QFE is pressure at the aerodrome, giving height above the aerodrome.

Icing temperature range

Icing risk is greatest between 0 and minus 20 degrees Celsius in visible moisture, where supercooled water freezes on impact.

Cold front weather

A cold front brings rapid lifting, squalls, showers and thunderstorms, followed by rapid clearing and improved visibility.

METAR and TAF

METAR reports current aerodrome weather; TAF forecasts it; SIGMET warns of significant hazards such as thunderstorms or turbulence.

Latitude and longitude distance

One minute of latitude equals one nautical mile; one minute of longitude equals one nautical mile multiplied by the cosine of latitude.

VOR radial

A VOR provides magnetic bearing from the station, called a radial; DME gives slant range to the same station.

ILS components

The localiser gives lateral guidance, the glideslope gives vertical guidance, and marker beacons or DME indicate distance to the threshold.

ADF relative bearing

An ADF shows relative bearing to a station; magnetic bearing equals relative bearing plus aircraft magnetic heading.

Go-around procedure

Apply full power, pitch for climb, retract flaps in stages, and advise air traffic control; do not turn back below 500 ft.

Engine failure after take-off

Maintain control, pitch for best glide speed, select a landing site ahead, and avoid turning back below 500 ft above ground.

Squawk codes

7700 means emergency, 7600 means radio failure, and 7500 means unlawful interference; set these codes when the situation applies.

MAYDAY and PAN PAN

MAYDAY is the distress call for grave and imminent danger; PAN PAN is the urgency call for a serious but non-immediate situation.

Lift formula

Lift equals half the air density multiplied by airspeed squared, wing area and lift coefficient; it rises with the square of speed.

Load factor in turns

Load factor equals one divided by the cosine of the bank angle; a 60 degree bank gives a load factor of two.

Induced and parasite drag

Induced drag decreases with speed while parasite drag increases with the square of speed; total drag is lowest at best glide speed.

Stall angle of attack

Stall occurs at the critical angle of attack, regardless of speed, weight or altitude; stall speed rises with weight and load factor.

Fuel planning components

Trip fuel plus contingency, alternate fuel, final reserve and taxi fuel; final reserve is typically 30 minutes for visual flight rules.

True airspeed increase

True airspeed increases about 2 percent per 1000 ft for a given indicated airspeed because air density decreases with altitude.

Endurance and range

Endurance equals fuel available divided by fuel flow; range equals endurance multiplied by ground speed, so wind affects range.

Service ceiling

The altitude at which the maximum climb rate falls to 100 feet per minute; climb performance decreases with altitude and temperature.