Version 2.5 released May 2, 2022.
Designed for iPhone, also works nicely on iPad.
And on Apple Silicon Macs.

New in Version 2.5: E6BJet displays turn radius, diameter, circumference and turn rate for the current speed and selected bank angle, plus the load factor. Also computes bank angle required for a given turn rate. Details here.

E6BJet performs the functions of traditional flight computer slide-rules, such as the E6B,
CR-3, CRP-5 and others, with a number of advanced additional features. These include:

  • QNH-QFE conversion,
  • crossover altitude calculation,
  • precision cold-temperature altitude corrections,
  • NEW: turn radius/diameter/circumference and turn rate/bank angle calculations,
  • temperature rise due to airspeed,
  • fuel weight & volume calculations for kerosene, wide-cut, and aviation gasoline fuels, using actual densities.

E6BJet also calculates sunrise, sunset and civil twilight times for any geographic coordinates on Earth (except directly at the poles), for dates ranging from January 1, 1900 up to December 31, 2999. Coordinates from publicly-available sources for a number of aerodromes, with their ICAO identifiers, are included, and you can edit, delete or add your own.

E6BJet can make full use of the altimeter function most iPhones provide, and even act as a baro-recorder. Still more advanced functions are already in work, and will be included in future updates.

E6BJet can be used for flight planning for any aircraft, from sport aeroplanes to airliners, and handles calculations well into the supersonic jet range. It is fully ready for the next-generation of pilots and aircraft.

The innovative interface, similar to modern aircraft flight displays and controls, allows instant “what-if” calculations, and keeps all relevant parameters in view at all times.

Watch an intro video here.

Results are shown in most commonly-used aviation units at the same time, eliminating any further conversion steps.

Scroll down and tap/click on the screen images to find out more about the functions.

Works with iOS 12.4 or later.


Click or tap the image for more information.
  • Calculate Calibrated, Equivalent, True Airspeed and Mach number for any altitude / flight level (up to 100 000 feet / 30 480 metres) and temperature.
  • See how an altitude change affects speeds and temperature.
  • Find crossover altitude for a given TAS and Mach number. Determine temperature rise due to airspeed & compressibility.
  • Set temperature, and see deviation from standard and effect on speeds, for any altitude.
  • NEW: Find turn radius (or diameter or circumference) and turn rate for any bank angle at the current speed. Also, calculate bank angle required to maintain a given turn rate.
  • Use this page to convert temperatures between Celsius and Fahrenheit, independently of any speeds.


Click or tap the image for more information.
  • Solve wind-triangle and groundspeed-time-distance calculations.
  • Crosswind and Head/Tailwind components always in view.
  • Get a visual representation of aircraft heading (true and magnetic), track, and wind direction.


Click or tap the image for more information.
  • Determine Indicated, Pressure, Density, True and (temperature-) Compensated Altitudes & Heights.
  • Easily adjust temperature / temperature deviation from ISA.
  • Use either sea-level (QNH) or station-level (QFE) pressure. Easily switch between them, and between altitudes and heights.
  • Results are displayed simultaneously in feet and metres.
  • on devices with a barometric sensor, optionally also display sensed pressure and corresponding altitude/height.
  • Optionally record altitude changes over time in a text file on your device, and access the recorded data using the Files app.
  • NOTE: The above illustration depicts a device with a barometric sensor, with both displaying and recording of device altitude data enabled. Not all devices have this sensor.


Click or tap the image for more information.
  • Calculate weight from volume and vice-versa, for various jet fuels (Jet A & JP8, Jet A1, Jet B & JP4, JP4 US, JP5) and for avgas.
  • Takes fuel density and temperature into account.
  • Volumes are shown in litres, imperial, and US gallons, weights in pounds and kilograms.
  • Use this tab to also convert between litres and gallons, and between pounds and kilograms, independently of fuel.


Click or tap the image for more information.
  • Calculate sun rise, set and civil twilight times for any location on Earth (except directly at the poles). Simply enter coordinates and select the date for which you want to see rise, set and twilight times.
  • Recall coordinates for stored locations. A number of aerodrome locations, and their coordinates obtained from publicly-available sources come pre-installed (one per ICAO region and country, plus a few extras).
  • Modify stored location data, or add your own additional locations.
  • Times are calculated in UTC, and Local if a time zone identifier or UTC offset is specified.
  • If a time zone identifier is specified, the calculated Local times automatically take into account Daylight Saving time, if used in the time zone.
  • A graphic display of times is also provided.
  • Location coordinates are displayed in 3 commonly used formats. You can choose which format will be used to enter coordinates, and switch instantly between them. This is also useful for simply converting among coordinate formats even if rise/set times are not needed.
  • Locations you create (or existing locations that you modify) can be exported for backup purposes, as well as for transferring them to your other devices.
  • You can set a default location to be displayed when the app launches.

Click here to see detailed calculation range limits.

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