Acknowledgements: Source - www.skybrary.aero

(Ed. Note: The following has been extracted from the complete article which can be viewed by following the above link)

Introduction to Pilot Memory Aids

Memory aids for pilots come in all shapes and sizes. Typically “mental hooks” such as mnemonics, acronyms, and aphorisms (concise sayings, usually witty); but may also include checklists, mechanical reminders and electronic displays. Pilot memory aids are typically used for:

·      learning

·      improving memory

·      making recall easier (quicker) and more likely,

·      reminding, 

·      preventing the omission of actions at the appropriate time and place,

·      improving decision-making and problem-solving,

·      directing focus

·      increasing vigilance, and

·      encouraging appropriate attitudes and behaviours

Memory Capacity

When pilots commence flying training they are quickly exposed to vast amounts of information (technical, operational, practical, theoretical) as well as having to learn, practice and develop their flying, flight and aircraft management skills. From “day 1” pilots learn to utilise mnemonics and aphorisms to remember checksprocedures and practices, and these techniques remain with them throughout their careers. Learning to use effectively such memory aids can help pilots in at least two distinct ways:

·      Freeing-up working memory during routine operations, and

·      Directing the mind towards required actions during periods of uncertainty, or intense activity and/or emergency; i.e. preventing distraction from less critical issues.

Information Levels

·       An example of a general memory aid may be the aphorism Aviate, Navigate, Communicate – this is a reminder of priorities and applies in any situation of uncertainty and emergency in order to prevent pilots from becoming fixated on an issue of minor importance.

·       An example of a moderately specific memory aid may be the acronym HASELL which can be used prior to performing acrobatic manoeuvres - Height, Airframe, Security, Engine, Location, Look-out

·       An example of a very specific memory aid might be an acronym for the emergency initial actions for an engine fire - SID– Shutdown engine, Isolate engine, Discharge fire suppressant.

Pilots flying simple GA aircraft, operating in a limited number of ways and environments, may tend to conduct all checks (and drills) from memory – remembered through the use of mnemonics. However, as the complexity of both aircraft and operations increase, pilots rely more on written procedures and checklists..

Non-mental Memory Aids

Pilots use the aircraft displays to aid their memories:

·      Mechanical or electronic “bugs” to indicate key information e.g. required track, take off/approach speeds.

·      When included in a pilot’s scan, digital or analogue displays provide reminders, e.g. radio frequencies, cleared altitude etc.

·      When the situation demands, pilots have been known to use other visualmemory aids, e.g. dayglow sticky labels on pulled circuit breakers, or a brightly coloured clipboard placed across throttles. These may be constant reminders that e.g. a system is not working, or fuel dumping is currently in progress.

·       The “ultimate” pilot memory aid is another crew member, specifically designated to pass information at a specific time, or when specific conditions are met, e.g. the non-flying pilot calling “1000 feet to level”.  


Many memory aids are simple aphorisms used to remember certain principles.

·      West is best, East is least – for applying magnetic variation to True tracks and bearings.

·      UNOS– Undershoot North, Overshoot South – to compensate for the lagging and leading action of compasses during turns.

Rules of thumb are common, although not always correct!

·      From High to Low, look Below! – this applies to the effects on an altimeter when either pressure and/or temperature change to a lower value. In both cases the altimeter will be over-reading.

·      Multiply groundspeed by 5 – to calculate the rate of descent required to fly a 3 degree glideslope.

General rejoinders to “pay attention” and/or “prioritise”.

·      Aviate, Navigate, Communicate – priorities in emergency and unusual situations.

·      Fly attitude- a reminder that a pilot should gain familiarity with the aircraft type pitch attitude at various flight phases.

·      Pitch, Power, Performance– priorities when executing a go-around.

 Some memory aids concern behaviour and professionalism.

·      IMSAFE – self-checking for ability to operate: Illness, Medication, Stress, Alcohol, Fatigue, Eating.

·      Look, Think, Act – a general reminder to avoid reactive and instinctive behaviour.

 Some memory aids apply as constant reminders that improve situational awareness.

·      CRAFT – Clearance, Routing, AltitudeFrequencyTransponder

·      MEA – Minimum, Expected, Assigned – assuring oneself that the cleared altitude/flight level is safe.

 Checklists are often remembered through mnemonics and acronyms, however, these will be specific actions for a particular type of aircraft.

·      CIGAR – Controls, Instruments, Gas, Attitude (trim and flaps), Run-up – example of before take-off checks.

·      FLARE – Flaps, Lights, Auxiliary fuel pump, Radar transponder on, Engine mixture – example of after take-off checklist.


Whilst they can be useful, mnemonics and other memory hooks, should notreplace the use of checklists, and any applicable legal and company requirements which need to be followed. 

 And when developing any memory aid, consideration should be given to the following questions:

·      memorability– can it be recalled easily? 

·      reliability– can each item be remembered accurately and consistently?

·      relevance and need– is there a better, safer, procedure or system available?

·      confusion– is it possible that the memory aid, or elements of it, can be confused with another?

·      test– has the memory aid been tested under operational and emergency conditions?


Tony Birth