Altitude control is one of the primary skills we learn as pilots and serves as the basis for aircraft separation in airspace around the globe. Pilots spend thousands of dollars on panel-mount altitude preselect and alerting systems to make sure the assigned altitude is not mistaken or forgotten. All it takes is one IFR flight with one of these systems and you’ll wonder how you ever got by without it.
The reality though is not all airplanes have this capability, but that doesn’t mean you have to resort to memory to keep track of ATC altitude assignments. An app called AltitudeAlert can help you with this task and give you visual and audible alerts should you deviate from your current altitude. The best part is the app is designed as a multitasking slide-over app, so you can run it right alongside your favorite EFB app, like ForeFlight or Garmin Pilot.
Flying with AltitudeAlert
AltitudeAlert has two display modes, Full-Screen and Slide-Over. When you first open the app you’ll see the Full-Screen mode, with the main controls on the left side of the screen. The Slide-Over view is a more practical option, but requires a few steps to activate it for the first time:
- Launch your primary in-flight navigation app
- Swipe up from the bottom of the screen to reveal the dock
- Touch and hold the AltitudeAlert icon, then drag it up until the app “elongates”
- Release your finger, and Altitude Alert will stay open on the right side of the screen.
- Swipe your finger from the left edge of the app to the right side of the screen to hide it, and swipe in from the right side of the screen to bring it back out again
AltitudeAlert uses the geometric altitude from your iPad’s internal GPS or third-party GPS accessory and corrects it for GPS error and atmospheric conditions. This corrected value is displayed as the “Reference Altitude” in green at the top of the app and is used to provide proximity and deviation alerts.
AltitudeAlert will then monitor the Reference Altitude. When the Reference Altitude is within 900’ of the target altitude selector, an aural and visual alert will be generated. After reaching the selected target altitude, AltitudeAlert then monitors the altitude set in the target altitude selector against the Reference Altitude. If the Reference Altitude exceeds the target altitude selector by +/- 200’, you’ll receive another aural and visual alert.
Prior to descent, set the Surface Temp, ALT Setting, and TO/LDG Field Elev for the conditions at the destination airport. Then set the Target Altitude Selector to the desired lower altitude or as cleared by ATC. AltitudeAlert then generates alerts using the same criteria as above.
During the final approach, press the LAND button. This will zero out the target altitude display and change the Reference Altitude display to a Magenta color. In this mode, AltitudeAlert will generate an aural alert at 1000’ AGL and 500’ AGL respectively for situational awareness.
Additionally, if the “Retractable Landing Gear” option is enabled, “Check landing gear down” will be annunciated after the 500’ alert. It’s important that you set the correct landing field elevation with the TO/LDG Field Elev controls to ensure accuracy.
Notifications and Sounds
When you first launch the app you’ll be prompted to accept push notifications, which are used to display alerts when approaching or deviating from an assigned altitude. You’ll want to set these as “Persistent” notifications from the main iPad settings screen so that they stay in view until you manually dismiss them.
Also, check to make sure the volume is turned up on your iPad so that the aural alerts come through. If you have a headset with Bluetooth capability, consider pairing your iPad to the headset to make sure you never miss an alert.