Element Track:Altitude adjustment

Altimeters

As any pilot knows, there are many different altitudes in aviation. The Element determines altitude using both GPS and barometric pressure, and its altitude display is customisable. You can select among three altimeters called ALT1, ALT2, and ALT3, and you can manually set the sea level barometric pressure. We will use the following definitions when explaining the altimeter functions:

• Absolute altitude – height above mean sea level (MSL)
• GPS altitude – MSL altitude indicated by GPS satellites
• Relative altitude – height above a known point such as an airfield
• AGL Altitude – height over the terrain directly below (above ground level)
• QNH – the actual air pressure at sea level
• Flight Level – altitude MSL, in hundred feet intervals, relative to the ISA pressure setting of 1013.25 hPa. FL17, for example, indicates that you are in the 1700' band, between 1650' and 1750' MSL.

ALT 1: Absolute altitude

ALT1 is your altitude above Mean Sea Level (MSL). Toggle between displaying ALT1 and ALT2 by pressing ALT1 / ALT2. ALT1 is automatically set to your GPS altitude as soon as the Element acquires a GPS signal. (Note that ALT1 flashes until the Element has calculated a precise reading.) This altitude calibration means, of course, that the QNH pressure setting is also automatically adjusted.

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  Long press to access ALT1 adjustments, short press to toggle between ALT1 and ALT2

You can manually adjust ALT1 by holding down ALT1 on your keyboard, which brings you into the ALT1 setting screen. There are three main reasons you might choose to adjust ALT1:

1. If you DO know your present altitude, but you DO NOT know your QNH setting. For instance, you notice a sign posted at the take-off giving the actual MSL elevation of the ramp. In this case, you might adjust your ALT1 to match the sign. You will notice that adjusting the altitude setting will also cause a change the QNH pressure setting.

Press and hold ALT1.
Use the arrow keys to adjust ALT1 to the desired reading.
Press OK.

2. If you DO NOT know your present altitude, but you DO know your barometric pressure. Perhaps you have an aviation weather report giving the local QNH setting, or perhaps you have a setting from air traffic control. In either case you can change ALT1 to reflect this pressure setting.

Press and hold ALT1.
Use the arrows to adjust ALT1 until QNH matches the desired reading.
Press OK.

3. If you want to cancel an adjustment and return to either standard pressure setting or GPS altitude. The F1 and F2 keys will allow you to quickly cancel any ALT1 adjustments and use a standard setting.

Press and hold ALT1.
Press F1 to confirm the choice to set ALT1 to FL-Alt, MSL using standard atmospheric pressure.
OR
Press F2 to confirm the choice to set ALT1 to GPS altitude.
Press OK.

ALT 2: Alternative altitude display

Toggle between displaying ALT1 and ALT2 by pressing ALT1 / ALT2. When ALT2 is toggled, your Element will not necessarily display the label ALT2, instead it will indicate whichever ALT2 configuration is presently selected. You can configure ALT2 to show any of four different values using the Instrument Settings menu.

Press and hold MENU, then use the arrow keys to select Instrument settings.
Press OK.
Use the arrows to select Alt2 mode and press OK.
Then select your preferred ALT2 mode.
Press OK.
Press ESC to return to the Main Setup Menu.

These are the four available choices for ALT2:

• GPS altitude: (The label GPS appears beside the altitude reading.) Note that you cannot adjust ALT2 when you have selected this option. ALT2 will only display the current GPS altitude.
• Flight Level: (The label FL appears beside the altitude reading.) Note that you cannot adjust ALT2 when you have selected this option, because the Flight Level display is always based on a standard atmospheric pressure value of 1013.25 hPa.
• ALT1 m/ft inverse: (If ALT1 is displayed in metres, then ALT2 displays true altitude in feet. The label ALT1 remains beside the altitude reading but the units change.) Note that you can adjust this value. Adjusting ALT2 in this mode will automatically adjust ALT1 as well.
• Relative altimeter: (The label ALT2 appears beside the altitude reading. Note that you can adjust this value.

These are the available adjustments for ALT2:

1. When in relative altimeter mode, you can rapidly reset the ALT2 relative altimeter to either your current GPS altitude or to zero by holding down the ALT2 key.

Press and hold ALT2.
Press F1 to set the relative altimeter ALT2 to 0.
OR
Press F2 to set the relative altimeter ALT2 to your current GPS altitude.
Press OK.

2. When in relative altimeter mode, you can adjust the ALT2 relative altimeter up or down using the arrow keys .

Press and hold ALT2.
Use the arrow keys to set the relative altimeter ALT2 to your desired value.
Press OK.


3. When in ALT1 m/ft inverse mode, you can adjust ALT2 up or down using the arrow keys . This automatically adjusts ALT1.

Press and hold ALT2.
Use the arrow keys to set the ALT1 m/ft inverse altimeter ALT2 to your desired value.
Press OK.

ALT 3: Relative altitude

Toggle between displaying ALT3 and the current time of day by pressing the ALT3 key. This altimeter always gives a relative altitude and is easy to reset to zero in flight using the Clear ALT3 (CLR A3) key. It has two main uses:

1. When your Element detects take-off, it automatically sets ALT3 to zero. In this way, ALT3 will indicate your height above (or below) the launch.
2. In flight, reset ALT3 to zero at any time by pressing CLR A3. This can be useful to monitor your height gain in a weak thermal.

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  Toggle between Alt 3 and time
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  Clearing Alt 3