True vs Magnetic Heading: Variation and Deviation Explained
How to turn a true course into a compass heading with wind correction, magnetic variation and deviation, with a worked example.
Aviation Guides
Aviation Guides
Aviation guides for student pilots, flight dispatchers and aviation enthusiasts: reading METAR and TAF weather reports, altimeter settings, flight levels, density altitude, crosswind components, weight and balance, fuel planning and flight-plan codes. Each guide explains the concept with worked examples and links to the matching USFITools calculator. Educational use only: always follow your aircraft flight manual, operator procedures and the regulations of your aviation authority.
Aviation Guides
IFR Alternate Requirements: The 1-2-3 Rule and Alternate Minimums
When an IFR flight plan needs an alternate under 14 CFR 91.169, the standard alternate minimums, and how the answer sets your IFR fuel.
Aviation Guides
Glide Ratio and Glide Distance: How Far Can You Glide?
How to work out engine-out glide range from height, glide ratio and wind, with a still-air table and a worked example.
Aviation Guides
Standard-Rate Turns: Bank Angle, Turn Radius and Load Factor
How much bank a standard-rate turn needs at any speed, how big the circle is, and why holding speeds and bank limits exist.
Aviation Guides
Mach Number Explained: Speed of Sound, TAS and Crossover Altitude
Why jets fly a Mach number at altitude, how the speed of sound depends on temperature, and how to convert Mach to true airspeed at any level.
Aviation Guides
Equal Time Point and Point of No Return Explained (ETP and PNR)
How to work out the equal time point and point of no return from distance, groundspeeds and endurance, with a worked 1,200 NM example.
Aviation Guides
VFR Fuel Reserve Rules: FAA, EASA, UK, Canada, Australia
Minimum VFR and IFR fuel reserves under FAA, EASA, UK CAA, Transport Canada and CASA rules, side by side, with a worked fuel plan.
Aviation Guides
Nautical Miles and Knots: Why Aviation Uses Them
Why a nautical mile is 1,852 m, how it links to latitude, how to measure distance on a chart, and quick conversions between knots, km/h and mph.
Aviation Guides
What Does ZZZZ Mean in a Flight Plan? Items 9, 13, 16 and 18
ZZZZ is the ICAO flight plan placeholder for an aerodrome or aircraft type with no designator. Where it goes, what you must add in Item 18, and a worked example.
Aviation Guides
ICAO vs IATA Airport Codes: How the Letters Work
Why an airport has both a 3-letter IATA code and a 4-letter ICAO code, what the ICAO letters mean region by region, and which code to use for tickets, flight plans and weather.