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Mnemonics and memory tricks

81 short tricks for the facts students mix up most: heading corrections, altimeter rules, right of way, transponder codes, V-speeds and more.

Subject

Navigation

TVMDC: "True Virgins Make Dull Companions"

  1. True
  2. Variation
  3. Magnetic
  4. Deviation
  5. Compass

The order of the headings. From True to Compass you apply variation, then deviation.

Navigation

CADET

  1. Compass
  2. Add
  3. East
  4. True

Going from Compass to True: add East errors, subtract West errors.

Navigation

"Variation west, magnetic best; variation east, magnetic least"

  1. West variation: Magnetic is bigger than True
  2. East variation: Magnetic is smaller than True

Use it to check that you added or subtracted variation in the right direction.

Navigation

"Longitude east, GMT least; longitude west, GMT best"

  1. East of Greenwich: local time is ahead
  2. West of Greenwich: local time is behind

Quick check when you convert local time to UTC.

Navigation

1 in 60

  1. 1° of angle is 1 NM off track for every 60 NM flown

Track error angle = distance off ÷ distance flown × 60.

Navigation

Closing angle

  1. Closing angle = distance off ÷ distance to go × 60

Add it to the track error angle to get back to track at the next point.

Navigation

The 3 times rule

  1. Height to lose in thousands of feet × 3 = distance to go in NM

A 3° descent path. Add a bit for slowing down.

Navigation

Rate of descent for 3°

  1. Ground speed × 5 = feet per minute

At 120 kt, that is about 600 ft/min.

Navigation

60 NM per degree

  1. 1 minute of latitude = 1 NM
  2. 1° of latitude = 60 NM

Measure distance on the latitude scale, never the longitude scale.

Navigation

"DST" triangle

  1. Distance
  2. Speed
  3. Time

Cover the one you want: D = S × T, S = D ÷ T, T = D ÷ S.

Navigation

Mach number

  1. M = TAS ÷ the speed of sound

Speed of sound depends on air temperature.

Navigation

Steer into the wind

  1. Wind from the right: head right of track
  2. Wind from the left: head left of track

The heading is always on the windward side of the track.

Navigation

UNOS

  1. Undershoot North
  2. Overshoot South

Compass turning errors in the Northern Hemisphere. When turning to north, roll out before the compass reads north.

Navigation

ANDS

  1. Accelerate North
  2. Decelerate South

On east or west headings, the compass shows a turn to the north when you speed up.

Navigation

Hold entry names

  1. Direct: turn onto the hold at once
  2. Teardrop: outbound at 30° off, towards the holding side
  3. Parallel: outbound parallel to inbound, on the non-holding side

The names describe the shape of the first outbound leg.

Navigation

Hold timing

  1. 1 minute outbound at or below 14,000 ft
  2. 1½ minutes above 14,000 ft

Standard turns are right-hand unless the chart says left.

Navigation

Convergency

  1. Convergency = change of longitude × sin latitude

It is zero on the equator and largest at the poles.

Navigation

Mercator versus Lambert

  1. Mercator: a straight line is a rhumb line
  2. Lambert: a straight line is close to a great circle

Great circle is the shortest route. The rhumb line crosses meridians at a constant angle.

Navigation

Airspeed chain: I-C-E-T

  1. IAS
  2. CAS
  3. EAS
  4. TAS

Correct for instrument and position error, then compressibility, then density.

Navigation

Radio navigation bands

  1. NDB: LF and MF
  2. VOR and localiser: VHF
  3. DME and glide path: UHF

Higher frequency is line of sight only.

Meteorology

"High to low, look out below"

  1. Flying from high to low pressure: the altimeter over-reads and you are lower than it shows

If you do not reset the altimeter, you will be lower than you think.

Meteorology

"From hot to cold, look out below"

  1. Flying into colder air: the altimeter over-reads and you are lower than it shows

Cold air is denser, so pressure falls faster with height.

Meteorology

Buys Ballot's law

  1. Stand with your back to the wind
  2. In the Northern Hemisphere, low pressure is on your left

Reverse it for the Southern Hemisphere.

Meteorology

Veer and back

  1. Veer: wind direction turns clockwise
  2. Back: wind direction turns anticlockwise

In the Northern Hemisphere, wind veers with height in the friction layer.

Meteorology

Lapse rates: 3, 2, less

  1. Dry adiabatic: 3 °C per 1000 ft
  2. ISA environmental: 2 °C per 1000 ft
  3. Saturated: less than 3

The saturated rate is lower because condensation releases heat.

Meteorology

ISA numbers

  1. 15 °C
  2. 1013.25 hPa
  3. 2 °C per 1000 ft
  4. tropopause 11 km (36,090 ft)
  5. −56.5 °C

The five numbers every exam asks about.

Meteorology

QNH, QFE, QNE

  1. QNH: altimeter reads elevation on the ground
  2. QFE: altimeter reads zero on the ground
  3. QNE: 1013.25 set, reads pressure altitude

"F" for field (zero height), "N" for nautical or sea level.

Meteorology

CAVOK

  1. Visibility 10 km or more
  2. No cloud below 5000 ft or the highest minimum sector altitude
  3. No cumulonimbus or towering cumulus
  4. No significant weather

Cloud And Visibility OK.

Meteorology

Cloud amounts: FEW, SCT, BKN, OVC

  1. FEW 1 to 2 oktas
  2. SCT 3 to 4
  3. BKN 5 to 7
  4. OVC 8

Count in eighths of the sky.

Meteorology

Cloud names

  1. Cirro: high and ice
  2. Alto: middle
  3. Strato: layer
  4. Nimbo: rain
  5. Cumulo: heap

Combine the parts: Nimbostratus is a rain layer.

Meteorology

Warm and cold front slopes

  1. Warm front: about 1 in 150, a long gentle slope
  2. Cold front: about 1 in 50, steep

Warm fronts give a long period of cloud and rain; cold fronts a short, sharp one.

Meteorology

Ahead of a warm front

  1. Cirrus
  2. Cirrostratus
  3. Altostratus
  4. Nimbostratus

In the order you see them as the front comes closer.

Meteorology

Thunderstorm stages

  1. Cumulus (up)
  2. Mature (up and down)
  3. Dissipating (down)

Heavy rain and hail are strongest in the mature stage.

Meteorology

TAF change groups

  1. BECMG: becoming, a lasting change
  2. TEMPO: temporary, under an hour each time
  3. PROB: probability of 30 or 40 per cent

BECMG for good, TEMPO for a short time.

Meteorology

Fog by numbers

  1. Fog: visibility under 1000 m
  2. Mist: 1000 m to 5000 m
  3. Temperature and dew point within 2 °C

Close temperature and dew point on a calm night warn of fog.

Meteorology

Cloud base estimate

  1. (Temperature − dew point) × 400 = cloud base in feet

A quick rule for convective cloud.

Meteorology

Indian seasons

  1. Winter
  2. Pre-monsoon
  3. Southwest monsoon
  4. Post-monsoon

January to February, March to May, June to September, October to December.

Meteorology

Wind and slope

  1. Anabatic: up the slope in the day
  2. Katabatic: down the slope at night
  3. Sea breeze: day
  4. Land breeze: night

"An" is up and "Kat" is down.

Meteorology

Icing types

  1. Clear ice: large drops, freezes slowly
  2. Rime ice: small drops, freezes at once, white and rough

Clear ice is the worse of the two.

Regulations

The 19 Annexes in groups

  1. 1 to 3: licences, rules, weather
  2. 4 to 5: charts, units
  3. 6 to 8: operate, register, airworthy
  4. 9 to 12: facilitation, telecoms, air traffic, search and rescue
  5. 13 to 15: accidents, aerodromes, information
  6. 16 to 19: environment, security, dangerous goods, safety management

Learn them in six chunks, not as a list of nineteen.

Regulations

Rules of the air: right-of-way

  1. Overtaking: overtake on the right
  2. Head-on: both turn right
  3. Converging: give way to the aircraft on your right
  4. Landing: the lower aircraft has priority

The right-hand rule.

Regulations

Who gives way

  1. Power-driven gives way to airships, gliders and balloons
  2. Airships give way to gliders and balloons
  3. Gliders give way to balloons

The less manoeuvrable aircraft has right of way.

Regulations

Transponder emergency codes

  1. 7500: hijack (unlawful interference)
  2. 7600: radio failure
  3. 7700: emergency

The numbers rise with 5, 6, 7 – hijack, radio, general emergency.

Regulations

Freedoms of the air

  1. First: fly across
  2. Second: land to refuel or repair, no passengers
  3. Third: carry from home State to another
  4. Fourth: carry back to the home State
  5. Fifth: carry between two foreign States on a flight to or from home

1 over, 2 stop, 3 out, 4 back, 5 beyond.

Regulations

Light signals to an aircraft in flight

  1. Steady green: cleared to land
  2. Flashing green: return for landing
  3. Steady red: give way and continue circling
  4. Flashing red: aerodrome unsafe, do not land

Green means go and red means stop, and flashing is the cautious version.

Regulations

Airfield light colours

  1. Runway edge: white
  2. Threshold: green
  3. Runway end: red
  4. Taxiway edge: blue
  5. Taxiway centreline: green

Remember that blue is for taxiway edges only.

Regulations

Order of Indian law

  1. Chicago Convention
  2. Annexes
  3. Aircraft Act 1934
  4. Aircraft Rules 1937
  5. DGCA Civil Aviation Requirements

From the broad treaty down to the detailed requirements.

Regulations

IMSAFE

  1. Illness
  2. Medication
  3. Stress
  4. Alcohol
  5. Fatigue
  6. Emotion

A self-check for fitness to fly. Say "I'm safe".

Regulations

PAVE

  1. Pilot
  2. Aircraft
  3. enVironment
  4. External pressures

Four groups of risk to check before a flight.

Regulations

Annex 13 words

  1. Accident: serious injury or death, substantial damage, or missing
  2. Serious incident: high probability of an accident
  3. Incident: anything else that affects safety

Think of the stages of how close it was to an accident.

Regulations

Dangerous goods classes

  1. 1 Explosives
  2. 2 Gases
  3. 3 Flammable liquids
  4. 4 Flammable solids
  5. 5 Oxidisers and peroxides
  6. 6 Toxic and infectious
  7. 7 Radioactive
  8. 8 Corrosives
  9. 9 Miscellaneous

Nine classes, in the UN order.

Regulations

Wake turbulence categories

  1. Light: up to 7000 kg
  2. Medium: 7000 to 136,000 kg
  3. Heavy: 136,000 kg or more

Super is for the very largest aircraft.

Regulations

Safety management

  1. Policy
  2. Risk management
  3. Assurance
  4. Promotion

The four parts of an SMS.

Technical General

Suck, squeeze, bang, blow

  1. Induction
  2. Compression
  3. Power
  4. Exhaust

The four strokes. A gas turbine does the same in one flow: intake, compress, burn, exhaust.

Technical General

PARE: spin recovery

  1. Power to idle
  2. Ailerons neutral
  3. Rudder full opposite
  4. Elevator forward

Check your aircraft's manual first; this is the standard idea.

Technical General

GUMPS: before landing

  1. Gas
  2. Undercarriage
  3. Mixture
  4. Propeller
  5. Switches and seat belts

A last check on final approach.

Technical General

CIGAR: before take-off

  1. Controls
  2. Instruments
  3. Gas
  4. Attitude (trim and flaps)
  5. Run-up

Do your own aircraft's checklist; this is a memory aid.

Technical General

Four forces

  1. Lift
  2. Weight
  3. Thrust
  4. Drag

In steady level flight: lift = weight, thrust = drag.

Technical General

Step on the ball

  1. If the ball is on the left, press the left rudder

The ball shows slip or skid in a turn.

Technical General

Pitot and static

  1. Pitot: ASI only
  2. Static: ASI, altimeter, vertical speed indicator

If the static source blocks, three instruments are wrong.

Technical General

Gyro rules

  1. Rigidity: stays pointing in one direction
  2. Precession: reacts 90° later in the direction of spin

Applies to the attitude indicator, directional gyro and turn coordinator.

Technical General

Gas laws

  1. Boyle: P × V is constant (temperature fixed)
  2. Charles: V ÷ T is constant (pressure fixed)
  3. Gay-Lussac: P ÷ T is constant (volume fixed)

Always use temperature in kelvin.

Technical General

Fine for take-off, coarse for cruise

  1. Fine pitch: low gear, high rpm, lots of thrust
  2. Coarse pitch: top gear, efficient cruise

Like gears in a car.

Technical General

High, hot, humid

  1. Density altitude goes up when the temperature rises
  2. Humid air is less dense

All three make take-off distance longer.

Technical General

Centre of gravity

  1. Forward: stable, higher stall speed, more down-force on the tail
  2. Aft: less stable, lower stall speed, more range

Stay inside the limits.

Technical General

V-speeds

  1. V1 decision
  2. VR rotate
  3. V2 take-off safety
  4. VX best angle
  5. VY best rate
  6. VS stall
  7. VS0 stall in landing configuration
  8. VFE flaps
  9. VNE never exceed
  10. VA manoeuvring

Know what each one is used for.

Technical General

Load factor in a level turn

  1. Load factor = 1 ÷ cos(bank angle)
  2. At 60° it is 2 g
  3. Stall speed rises with the square root of the load factor

A steep turn means a higher stall speed.

Technical General

Avgas colours

  1. 100LL: blue
  2. 100: green

Jet A-1 is clear or straw-coloured.

Technical General

Carburettor icing

  1. Can happen well above freezing
  2. Use carb heat before closing the throttle

The air cools as fuel evaporates and as the throttle restricts the airflow.

Radio Telephony

MAYDAY and PAN PAN

  1. MAYDAY: from the French "m'aider", help me, distress
  2. PAN PAN: from "panne", breakdown, urgency

Both are spoken three times.

Radio Telephony

Number pronunciation

  1. 3 is "tree"
  2. 5 is "fife"
  3. 9 is "niner"
  4. 1000 is "tousand"

They avoid mix-ups in noisy radio.

Radio Telephony

Message priority

  1. Distress
  2. Urgency
  3. Radio direction finding
  4. Flight safety
  5. Meteorological
  6. Flight regularity

Short form: DUD-FMF, for Distress, Urgency, Direction finding, Flight safety, Met, Flight regularity.

Radio Telephony

MAYDAY call order

  1. MAYDAY three times
  2. Station called
  3. Own call sign
  4. Nature of emergency
  5. Intentions
  6. Position, level, heading

Who, what, what next, where.

Radio Telephony

Position report order

  1. Call sign
  2. Position
  3. Time
  4. Level
  5. Next position and ETA

Five items, always in the same order.

Radio Telephony

Q codes: bearings

  1. QDM: magnetic heading to the station
  2. QDR: magnetic bearing from the station
  3. QTE: true bearing from the station
  4. QUJ: true track to the station

M and R go together: Magnetic and Radial from the station.

Radio Telephony

Q codes: altimeter

  1. QNH: reads elevation on the ground
  2. QFE: reads zero on the ground
  3. QNE: standard 1013.25

Same as the meteorology note, here for the radio.

Radio Telephony

ROGER is not YES

  1. ROGER: message received
  2. WILCO: will comply
  3. AFFIRM: yes
  4. NEGATIVE: no

WILCO includes ROGER, so never say both.

Radio Telephony

Readability scale

  1. 1 unreadable
  2. 2 readable now and then
  3. 3 readable with difficulty
  4. 4 readable
  5. 5 perfectly readable

Used in radio checks.

Radio Telephony

Radio bands

  1. HF: 3 to 30 MHz, long range
  2. VHF: 30 to 300 MHz, line of sight
  3. UHF: 300 to 3000 MHz

The aviation voice band is 118 to 136.975 MHz.

Radio Telephony

Emergency frequency

  1. 121.5 MHz on VHF
  2. 243.0 MHz on UHF

The UHF frequency is exactly double the VHF one.

Radio Telephony

Call sign abbreviations

  1. Use the full call sign on first contact
  2. Shorten it only after the ground station has done so

ATC decides when the short form is safe.

How to use these

A memory trick is only a hook. Read the card, say the parts aloud, then check yourself in Practice or with a game. If you invent a better trick, keep it: your own are the ones you will remember in the exam.

Study aid only. Some tricks are simplified, and aircraft checklists differ. Always follow the manual for your aircraft and the current DGCA and ICAO publications.