Author: chiefpilot

Release 2.60 available later today, April 22, 2024

We’re glad to announce that the latest version of E6BJet has just been approved by Apple, and will become available in the App Store during the course of today.

This new release adds new features, and restores access to the device altimeter readings, which had stopped displaying for users who upgraded to iOS 17.4 and 17.4.1.

New features added

1) Display of Device Altitude is now enabled by default.

On the Altitudes tab, device altitude is now displayed by default, if your device is equipped with a barometric pressure sensor – which is true for nearly all newer iPhones and iPads.

In earlier versions, you had to launch the Settings App, find the entry for E6BJet, and enable the display (and optionally recording) of device altitude information. By default, these options were turned off, making the features hard to discover.

The first time you switch to the Altitudes tab, you will be prompted once to allow, or deny, access to your Motion & Fitness activity. Allowing this will let E6BJet display readings from the device’s altimeter.

If you do not allow access, device altitude won’t be accessible, and will not be displayed until you grant permission. All other features of E6BJet will continue to work.

You can revoke or grant/reinstate permission for E6BJet to access device altitude at any time, by launching the Settings App, selecting Privacy & Security – Motion & Fitness, and toggling the permission switch for E6BJet.

2) Values now sync across tabs.

True Airspeed, Pressure Altitude and Air Temperature values are needed on several different tabs. Changes to one of these values on one tab now propagate to the other tabs. This gets rid of the need to enter the same value multiple times.

3) Onboarding added with guidance on the use of thumbwheels and locking.

We’ve added a short onboarding, to better let you see – and try – the features the thumbwheels provide for entering values.

The “locking” functionality, which lets you keep a selected value constant, is also described in the onboarding.

4) Temperature can now be adjusted in 0.1-degree increments.

This allows more precise entry of temperatures, and gives more accurate results in calculations that take temperature into account.

Thank you for your feedback and continued support, from the E6BJet Team!

NOTAM – Device altimeter not displayable starting with iOS 17.4 & 17.4.1


We are sorry to have to report a problem, with our App no longer able to display barometric altitude, once you have upgraded your device to iOS 17.4 / 17.4.1. We found out about this on April 10, 2024.

No calculations or other functions are affected.

The problem

If you have upgraded to iOS 17.4 or 17.4.1, E6BJet displays dashes in place of device (barometric) altitude and actual sensed pressure, despite display being enabled. Recording of altitude data also no longer takes place, even if it was enabled.

If you are using an older version of iOS, you will not be affected.

Unfortunately, there appears to be no workaround to reenable showing device altitude. We will need to release a new version of E6BJet.

We are targeting the last week of April 2024 for this new release.

[Update – April 12, 2024: there is an indication that the problem will be resolved with iOS 17.5, without any changes to the App needed. However, because we have no way of knowing when iOS 17.5 will be released – it is currently in testing – we will maintain the above target to release our new version. A solution is already implemented and being tested.]

The cause

Display (and optionally recording) of barometric altitude defaults to OFF, in E6BJet (current version 2.50 and older), and must be explicitly enabled in 2 places:

1) in the iOS Settings, under E6BJet, the ‘DISPLAY ALTIMETER DATA if available must be ON;

2) in the iOS Settings, under Privacy – Motion and Fitness, Fitness Tracking must also be ON;

There is a long-standing Apple requirement for all Apps to declare (in the code) that they wish to access device motion information (which includes altitude/barometric data). The intent was that with this declaration, iOS would eventually ask users for consent before motion information is allowed to be displayed for the first time. This is in line with Apple’s commitment to privacy, with which we very much agree.

We included this declaration back in 2021, when we released version 2.10 of E6BJet.

Because we only access altitude, but no other motion information, iOS versions before 17.4 provided the data without asking for consent, as long as users had enabled the Fitness Tracking option under Motion & Fitness. With iOS 17.4 (and 17.4.1), Apple now enforces that users must give consent – via a dialog box – when access to motion is attempted, but unfortunately not when accessing altitude only. So in our case, consent is never asked for, iOS assumes it has been refused, and this results in E6BJet not being able to access device barometric data. When we detect this, we display dashes, instead of altitude and sensed pressure. Recording also won’t occur even if enabled.

We very much regret the inconvenience to our users, and will have this resolved shortly.

Rest assured that E6BJet, in all versions past, present and future, respected and will respect the above settings as well as all other privacy settings. The App has never accessed barometric data unless enabled as described, and will never do so if not enabled.

Regards from the E6BJet crew, and please standby for the new release.

End of Support for iOS 12.x

Dear Crewmembers,

Since first releasing E6BJet, we have supported all versions of iOS beginning with iOS 12.4.

But the technology Apple provides to create the App has evolved in the last 3 years. Continuing to support older versions is beginning to limit us, as we then won’t be able to use the newer features Apple has introduced since 2020.

Apple requires us to support the current version of iOS (now 16.2) as well as the 2 preceding ones (15.x and 14.x).

We are still evaluating whether also supporting iOS 13.x would conflict with our new features roadmap, with a final decision to come shortly after this year’s Developer Conference (WWDC 2023).

However, regarding iOS 12.x, the bell has tolled. The next release of E6BJet will no longer support iOS 12.x.

It’s not without a tinge of sadness that we are giving this up, as we know of quite a few users who are perfectly happy with older devices, and do not wish to discard them when they still work. For them, new releases of E6BJet will no longer be available, although they can of course continue to use the current version (2.50).

Thanks for your continued interest in E6BJet, and wishing you Happy Landings!

Happy 2023

Here’s to a healthy, happy and successful new year for everyone.

We’re looking forward to publishing a new version of E6BJet with additional functions. We are aiming for this in the second quarter of this new year.

From the crew at, cheers!

Release 2.5 now available, adds turn radius/diameter calculations

Dear Crew,

We are happy to announce the release of the latest version of E6BJet. It will become available during the course of today on the App Store.

You will now see, on the Speeds tab, turn radius (or diameter, or circumference), turn rate, and also load factor. These will be continuously updated as speed changes occur.

You can vary the bank angle to see the effect on turn radius and rate. You can also modify the turn rate and see the required bank angle to maintain the given rate. Turn radius can be displayed in Nautical miles, Kilometres, feet, metres or Statute miles.

We also got rid of some unexpected display clipping on iPads, which occurred at first launch until it was rotated to landscape mode.

There were other changes to the app, of the “under the hood” type, to prepare for the future addition of other navigation calculations that are useful, but impractical to do using slide rules. Stay tuned!

Thank you for your purchase and your feedback, and many happy landings ahead to all!

NOTAM – “E6BJet needs to be updated” error when launching the app.

Dear Crewmembers,

Some of you have encountered a dialog box stating ‘The developer of this app needs to update it to work with this version of iOS’, when trying to launch E6BJet. This has been reported to occur on some iPads with iOS version 15.2.

If you encounter this dialog box, simply reinstall E6BJet from the App Store. To do so, using your iPhone or iPad, tap on the ‘Available on App Store’ button below, and when the E6BJet icon is displayed, tap the cloud download symbol next to it to re-download and install the app.
You can also launch Apple’s App Store App, search for the app by its name, E6BJet, and then tap the cloud download symbol.

E6BJet in its current version (2.10) is designed to work with all versions of iOS starting with iOS 12.4, and tested with the latest version – as of today, 15.2.1 for iPhones and iPads. The cause of the error, which is intermittent, is mysterious at the moment, as there have been no recent updates to E6BJet. We are still working on new features, and hope to have a new version available by April 2022.

Cheers and as always happy landings!

Release 2.10 is live on the App Store

This version changes the thumbwheels/sliders, making them much more responsive. Otherwise there is no change to the functions already provided.

When turning a thumbwheel/dragging a slider slowly, reaction is more natural and more sensitive to even small changes in speed.

If the thumbwheels/sliders are flicked, response is now much faster, allowing you to get to a desired value quicker.

We hope you like this change. Do let us know your thoughts on it.

App Store Search

E6BJet can currently be purchased in all countries where the Apple App Store is available. It has come to our attention that in some places, searching for E6BJet by its name will not work. The search term will be substituted by something else, and the search results will list a number of Apps that have no relation to E6BJet, nor to the functions our App provides.

Apple are investigating this at the moment, and we certainly hope that a solution will be found that will cause E6BJet to appear in the search results when its full name is used.

Update (04 June): Search issue has been resolved.

If you are encountering difficulties finding E6BJet on the App Store, you can:

a) From your device, tap on the ‘Download on the App Store’ button below, or,

b) Use ‘E6B’ as a search term in the App Store app. E6BJet will then appear in the list of Apps that match this keyword.

Cheers and Happy Landings!

Release 2.0 brings sunrise/set and twilight calculations

Dear Crewmembers,

We’re happy to announce that we’ve just made our latest release (2.0) available on the App Store. It should become visible during the course of the day. For existing customers, the update will appear automatically in the App Store app.

It adds calculation of sunrise, sunset and civil twilight times for any geographic location on Earth (except directly at the North and South poles), for dates ranging from January 1, 1900 to December 31, 2999.

Locations can be given an identifier of up to 5 characters/digits, and stored for quick retrieval. A number of aerodrome locations, with coordinates from publicly-available sources, are already provided (one location per ICAO region and country, plus a few extra). You can edit these, and add your own.

All the details can be found here.

We also significantly expanded the offline help text (to view, tap the ‘question mark’ button on each tab), and fixed the pagination dots issue I mentioned in my previous post.

We used the last months to not only develop this new functionality, but to make under-the-hood changes to pave the way for more upcoming features. Very shortly (before the end of May) we are releasing another update that provides a significant improvement to how the thumbwheels respond to touch. We’ve been looking to fix that for quite some time, and are very pleased with the results in our tests.

There is more in the works. The app now has 5 feature tabs (Wind, Speeds, Altitudes, Fuel and Sunrise), and for the next major feature (and the sixth and subsequent tabs), we need to do some more behind-the-scenes preparations. On the way there, we’ll continue to roll out improvements which you have suggested.

Thank you very much for your custom, and for your feedback, and as always happy landings!

NOTAM – Help displays missing pagination dots in iOS 14.0 and later.

Dear Crewmembers,

Seems a gremlin has gotten into the help displays (which you can access by tapping the ‘?’ button on the various tabs).

The Speeds, Altitudes and Fuel W/V help displays have two pages of text. To move from one page to the other, swipe left (or right). To dismiss the help display, tap the amber ‘X’ button that also shows.

Help displays with more than one page show pagination dots (also in amber) near the bottom of the tab on iOS 12.x and 13.x. However, starting with iOS 14.0, the dots have gone missing, although swiping left & right works just fine.

Thanks for pointing this out. A fix will be included with the upcoming release of version 2.0.

Please be sure to view the User Guide pages here on the website for details on all the functions, and of course keep your feedback coming!

Thank you, happy landings and cheers!

Release 1.5 available

We made improvements on the Wind tab.

Thanks to your suggestions, we made the following changes.

  1. The time thumbwheel now works as one would expect.
    Previously, when solving for groundspeed (and heading or track), the time thumbwheel would not update time values unless time was also “locked” for groundspeed changes. The same went for the distance thumbwheel.
  2. The maximum limit for wind speed, 350 knots, is now consistently applied. When solving for wind (direction and speed), combinations of TAS and groundspeed are now limited to those which give a wind speed of 350 knots or less.
    Previously it was possible to solve for wind and obtain results of more than 350 knots. But then switching to solve for any other values would prevent any inputs unless the wind speed was first reduced to 350 knots or less.

A note on thumbwheel behaviour.

Most values have hard limits. For example, TAS must be from 0 (or 1) to 2 500 knots, throughout E6BJet. If you attempt to turn the TAS thumbwheel to a value outside this range, it will stop rotating any further, as one would expect, and thereby provide a visual indication that the limit has been reached.

But if you are changing altitude, and doing so might cause the calculated TAS to exceed its limits, then the Altitude thumbwheel will continue to rotate – since the altitude limit has not been reached. But the altitude value will not change anymore, due to the limit on TAS.

In summary, if a thumbwheel can still be turned but its associated value no longer changes, it is because another, related value has reached its limit. If a thumbwheel doesn’t turn anymore, its associated value is now at its limit.

For details, see Calculation limits in the User Guides section.