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Practical guides for pilots
Plain-language explainers on the weather, briefing, and regulatory basics every pilot revisits, each grounded in primary sources. The library is just getting started.
Guided paths
Prefer to follow a subject from the start? These ordered paths take one topic and walk through it step by step.
- 5 guides
Decode the weather
Start with the raw reports and forecasts a pilot reads before a flight and learn to decode them in order, from the routine observation to the warnings that change a plan. Work through each one and the codes stop getting in the way.
Start the path - 5 guides
Duty, rest and flight time limits
The rules that decide how long you can work and how much rest you owe yourself, taken one layer at a time. This path walks from the basic definitions out to the cumulative limits and the standby rules that sit alongside them.
Start the path - 5 guides
Plan a VFR cross-country
The decisions behind a visual cross-country in the order you make them: the airspace you will cross, the minima you fly to, the fuel you carry, the alternate you keep in reserve, and the wind across the runway at each end.
Start the path
Cold-temperature altimeter corrections
Why a pressure altimeter over-reads in cold air, leaving you lower than indicated, and how to correct minimum altitudes for temperature on an approach in mountainous or freezing conditions.
- Operations
Mode S and ADS-B explained
How Mode S adds a 24-bit address, selective interrogation and a data link to the transponder, the difference between elementary and enhanced surveillance, and how ADS-B broadcasts your GPS position.
4 min read Read - Operations
The Global Reporting Format for runway conditions
How the Global Reporting Format (GRF) describes a contaminated runway, including the runway condition code (RWYCC) from 6 to 0, the assessment matrix (RCAM), and how the report is split into thirds.
5 min read Read - Operations
Top of descent and the 3:1 rule
How to work out your top of descent with the 3:1 rule, the 60-to-1 relationship behind it, and the rate of descent that holds a roughly 3 degree path, with a worked example.
4 min read Read - Briefing
ICAO vs IATA codes explained
The difference between the 4-letter ICAO location indicators used for flight planning and weather and the 3-letter IATA codes on your boarding pass, plus airline codes and callsigns.
3 min read Read - Operations
Mach number, true airspeed and the speed of sound
How the speed of sound depends on temperature, why Mach number rises as you climb at a constant true airspeed, and how indicated, calibrated, true airspeed and Mach relate.
3 min read Read - Weather
How to read a surface analysis chart
Decode a surface analysis chart: isobars and the pressure gradient, highs and lows, warm, cold and occluded fronts, and what the big picture tells you before you read the METAR.
3 min read Read - Operations
Squawk codes and transponders explained
What a transponder squawk code is, the difference between Mode A, C and S, and the emergency codes 7500, 7600 and 7700 every pilot must know.
3 min read Read - Weather
The International Standard Atmosphere (ISA)
What the ICAO International Standard Atmosphere is, its sea-level values and lapse rate, and how ISA deviation underpins altimetry, performance and density altitude.
3 min read Read - Operations
Wake turbulence categories and separation
Why aircraft trail wingtip vortices, the ICAO Light, Medium, Heavy and Super categories by maximum take-off mass, and how wake separation keeps a following aircraft clear.
3 min read Read - Weather
How to read a SIGMET and an AIRMET
What SIGMETs and AIRMETs warn of, the phenomena codes, how long each stays valid, and a worked SIGMET decoded field by field, with the ICAO baseline and the US differences.
5 min read Read - Weather
How to read a METAR
A plain-language guide to decoding a METAR field by field, with a worked example and the EASA/UK and FAA differences that trip pilots up.
5 min read Read - Weather
How to read a TAF
Decode a Terminal Aerodrome Forecast, including the FM, BECMG, TEMPO and PROB change groups, the validity period, and how a forecast differs from a METAR observation.
4 min read Read - Briefing
Understanding NOTAMs
What a NOTAM is, how the ICAO format and Q-line are built, the difference between NOTAMN, NOTAMR and NOTAMC, and how to deal with NOTAM overload.
4 min read Read - Regulations
Flight time limitations explained
Flight time, duty, flight duty period and rest, explained plainly, with the EASA/UK CAA and FAA limits attributed to each authority. Numbers differ by authority and change, so always check the current rule.
4 min read Read - Operations
Stabilised approaches and CDFA
Why a continuous descent final approach beats dive-and-drive, what a stabilised approach actually means, and where the 1000 ft and 500 ft gate heights come from.
4 min read Read - Logbook
Keeping a digital logbook
What a pilot logbook has to record and why, plus the EASA/UK and FAA differences in logging pilot-in-command time, night, and recency that catch people out.
4 min read Read - Briefing
The offline-first preflight briefing
What the rules require you to check before flight, how to build a self-brief, and the honest difference between offline-first and working fully offline.
4 min read Read - Weather
Density altitude and aircraft performance
What density altitude is, how to estimate it from pressure altitude and temperature, and why high, hot and humid conditions quietly rob an aircraft of performance.
4 min read Read - Weather
Aircraft icing explained
How airframe ice forms, the difference between rime, clear and mixed ice, what makes supercooled large droplets so dangerous, and where to find the icing forecast.
5 min read Read - Weather
Altimetry: QNH, QFE and the standard setting
What QNH, QFE and the standard pressure setting actually do to your altimeter, the difference between transition altitude and transition level, and the EASA and FAA conventions that differ.
5 min read Read - Briefing
How to read a PIREP
Decode a pilot weather report field by field, understand the UA and UUA types and the slash-coded elements, and see how a PIREP fills the gaps between weather stations.
4 min read Read - Briefing
The AIP and the AIRAC cycle
What an Aeronautical Information Publication is, how its GEN, ENR and AD parts are organised, and why aeronautical data changes on the fixed 28-day AIRAC cycle.
4 min read Read - Briefing
Decoding the ICAO flight plan
How the ICAO flight plan form is built, with a field-by-field decode of Item 10 equipment and capabilities and Item 18 other information, plus the codes that trip filers up.
4 min read Read - Operations
Airspace classes explained
The ICAO airspace classes A to G, the service and separation each one provides, and how the US, Europe and the UK implement the same letters differently.
4 min read Read - Operations
Mass and balance basics
What datum, arm, moment and centre of gravity mean, how to work a centre-of-gravity calculation step by step, and why staying inside the envelope matters as much as staying under the maximum mass.
4 min read Read - Operations
Declared distances: TORA, TODA, ASDA and LDA
What the four declared distances mean, how clearway and stopway extend them, and why the length of runway you can actually use is rarely just the runway.
4 min read Read - Operations
Crosswind components
How to resolve a reported wind into its crosswind and headwind components with simple trigonometry, a worked example, the sine rule of thumb, and what a maximum demonstrated crosswind really is.
4 min read Read - Operations
Holding patterns explained
The standard holding pattern, how the legs are timed, the three entry procedures, and the maximum holding speeds, with the ICAO and FAA figures attributed because they differ.
4 min read Read - Regulations
VFR weather minima and cruising levels
The visibility and distance-from-cloud minima for visual flight, and the semicircular cruising-level rule, with the ICAO baseline and the EASA and FAA figures attributed because the units and numbers differ.
4 min read Read - Regulations
Fuel planning and reserves
Why a flight carries more fuel than the trip needs, the ICAO baseline, the FAA VFR and IFR reserve rules, and the EASA fuel-scheme components, each attributed because the numbers differ.
4 min read Read - Logbook
Recency and currency
The difference between being legally current and being proficient, with the EASA and FAA recent-experience rules for carrying passengers, night flight and instrument flight, each attributed to its authority.
4 min read Read - Logbook
Pilot function and logging roles
What P1, PICUS, P2 and dual mean under EASA, how the FAA categories differ, and the crucial difference between logging pilot-in-command time and being the pilot in command.
7 min read Read - Regulations
Standby and reserve duty
What standby and reserve mean, how airport standby differs from standby at home, how the FAA handles long-call and short-call reserve, and how standby converts into duty and the flight duty period.
8 min read Read - Logbook
Logging instrument time
What actually counts as instrument time, the difference between actual and simulated conditions, why being on an IFR flight plan is not enough, and what the FAA and EASA require you to record.
7 min read Read - Regulations
Cumulative duty and flying-hour limits
How the rolling 28-day, annual and weekly limits on flight time and duty actually work, why a rolling window is not a calendar month, with the EASA and FAA figures attributed.
7 min read Read - Logbook
Logging night flying time
How night is defined for logging under the FAA and EASA, why the FAA has two different nights, what civil twilight means, and how to work out the night portion of a flight.
7 min read Read - Regulations
Acclimatisation and crossing time zones
Why your body clock changes the flight duty period you are allowed, how EASA defines an acclimatised state and the FAA defines being acclimated, and what the window of circadian low means.
8 min read Read - Weather
Fog, mist and the dewpoint spread
Why the gap between temperature and dewpoint predicts fog, the difference between mist and fog in a METAR, and the main fog types from radiation to advection.
8 min read Read - Regulations
Rest requirements and minimum rest
What counts as a rest period, how EASA and the FAA set the minimum rest before a duty, the idea of a sleep opportunity, and the weekly rest that protects against cumulative fatigue.
7 min read Read - Weather
Wind shear and low-level wind shear
What wind shear is, why microbursts and gust fronts are so dangerous near the ground, how it changes an aircraft's performance, and the warnings and forecasts that flag it.
8 min read Read - Briefing
How aviation data goes stale
Every weather and NOTAM product has an issue time and a validity, and once you are offline you hold a snapshot. Here is how METARs, TAFs and NOTAMs expire, and why the timestamp matters.
7 min read Read - Weather
Thunderstorms and convective weather
What makes a thunderstorm, the three stages of its life, the hazards from turbulence to hail and microbursts, and how the convective SIGMET warns you, with avoidance distances from the FAA.
8 min read Read - Regulations
Duty time, flight time and the flight duty period
The four terms at the heart of every fatigue rule, how the maximum flight duty period is built from report time and sectors, and how EASA and the FAA each handle extensions.
7 min read Read - Briefing
What is in a Pre-flight Information Bulletin
What a PIB is, how it packages the NOTAMs for your route, the difference between aerodrome, area and route bulletins, and why it is a snapshot you have to refresh.
7 min read Read - Weather
Setting personal weather minimums
What personal minimums are, how to build a set from ceiling, visibility and wind, and how to use the PAVE and IMSAFE checklists to keep your own limits honest.
7 min read Read - Briefing
Choosing an alternate aerodrome
When an alternate is required, the FAA 1-2-3 rule and alternate minimums, the EASA planning-minima approach, and the practical checks of weather, approaches, runway and services.
7 min read Read - Weather
Flight rules: VFR, MVFR, IFR and LIFR
What the colour-coded flight categories mean, the exact ceiling and visibility boundaries set by the NWS and FAA, and why a flight category is not the same as the legal VFR minima.
7 min read Read - Briefing
NOTAM categories and time windows
How NOTAMs are sorted by scope and subject, how the validity fields B, C and D set the time window, and what PERM and EST mean, so you can triage a long briefing package.
8 min read Read - Weather
Reading winds and temperatures aloft
How to decode a winds and temperatures aloft forecast field by field, including the coding trick for strong winds, with a worked example and how to use it for cruise planning.
8 min read Read - Briefing
Decoding NOTAM Q-codes and abbreviations
A deeper guide to the NOTAM Q-line: the five-letter Q-code, the traffic, purpose and scope qualifiers, the height and coordinate fields, and the contractions NOTAMs are written in.
8 min read Read - Weather
How to read an ATIS
What the ATIS broadcast contains, how the information letter and runway-in-use work, how it differs from a METAR, and the EASA/UK and FAA conventions that trip pilots up.
7 min read Read