Flying TeleMega with AltosUI on iPhone

TeleMega is Altus Metrum’s heavy-lift flight computer — full 3-axis IMU, six pyro channels, and a separate pyro battery. When you fly TeleMega with AltosUI on iPhone you get the richest display the app produces, because TeleMega sends the most data. This guide walks what a TeleMega flight looks like tab by tab.

What TeleMega reports

TeleMega (v1 through v7) reports a full 3-axis IMU, six pyro channels, and a separate pyro battery alongside the main flight-computer battery. The v7 hardware supports 30V voltage dividers, so higher-voltage pyro setups report cleanly. You will see tilt data during boost, continuity status for six channels instead of two, and two battery voltages to watch. What you see depends on what the hardware sends, and TeleMega sends a lot.

The canonical hardware reference is altusmetrum.org/TeleMega.

On the Pad

The Pad tab is where TeleMega’s extra channels become obvious. You see whether the flight computer is armed, whether each of its six pyro channels has continuity, whether GPS has locked with enough satellites to be useful, and the firmware version.

The battery view is dual: the main flight-computer battery and the separate pyro battery both report. That lets you confirm the pyro stack has its own healthy supply before you leave the pad — useful on clustered or staged flights where the pyro current draw matters. The receiver’s own battery and location round out the view so you know the ground side is healthy too.

Live on the Flight tab

Once the rocket leaves the rail, the Flight tab shows the current state, current and maximum height, current and maximum speed, tilt during boost, and the range, bearing, and elevation to the rocket relative to your position. Tilt is the TeleMega-specific addition: with a full 3-axis IMU on board, the app can show you how far the airframe has rotated off vertical during the boost phase.

Voice narration calls out state transitions — pad, boost, coast, apogee, drogue, main, landed — and peak values as they happen. The voice-callouts guide has the full call list. Direction-aware speed callouts keep you oriented: “ascending at N m/s” during boost and coast, “descending at N m/s” during descent.

On the Map

TeleMega’s GPS drives a full Map tab: your rocket’s ground track plotted over an Apple Maps basemap, with your position, the pad, and the rocket linked by lines. Online tiles or your pre-downloaded offline tiles, with Road, Hybrid, and Satellite map types. The Launch Site overlay is available if you enabled it in settings.

Walking to the rocket

The Recover tab is fully featured when TeleMega is flying. The default List mode shows bearing, direction, and distance from your position to the rocket’s last reported GPS position, along with the rocket’s coordinates and the flight’s maximum values. The Map mode is the dedicated Recovery Map walking view; the AR mode is the AR Recovery HUD. Both are covered in depth in the AR recovery guide.

The dashed GPS Uncertainty Circle is drawn around the reported position in both modes, sized to the flight computer’s reported HDOP. A large circle is useful information — it tells you the rocket probably landed somewhere with weak satellite reception, so search wider.

IDLE mode and pre-flight igniter testing

IDLE mode is prep-area work, not pad-side work. At the prep table or trailer, with the receiver within radio range of the TeleMega, you can put the receiver into IDLE mode to query device state, set the callsign, read configuration, and run a continuity-protected igniter test with countdown guards. For TeleMega specifically, the igniter test covers all six pyro channels, which saves a lot of hassle on clustered or staged builds — you verify continuity at the prep area before the rocket ever goes to the pad. Once you carry the airframe out and power up vertical, the flight computer wakes in Pad mode and is transmitting; IDLE is done by then.

Replay and post-flight review

After you’ve packed up, Flight Replay plays the recorded .telem file back through the full telemetry pipeline — the same Pad, Flight, Map, and Recover tabs that showed it live. Actual timing reproduces the original packet intervals; Fast delivers packets at one-second intervals for a quick scan. Useful on TeleMega flights for watching the tilt trace rise through boost a second time when you’re not also trying to keep eyes on the sky.

Back at the car

AltosUI writes a .telem file for the flight automatically, named by date, serial, flight number, and receiver. The iOS Files app exposes the file; Quick Look gives you a summary card without launching AltosUI; Share to AltosUI generates the full on-device Flight Report. The Flight Report is especially rich for TeleMega because the report’s stability metrics section pulls from IMU data — something only IMU-equipped flight computers like TeleMega produce. See the Flight Report PDF guide for the export path and the telem-files guide for file management.

For the full field workflow, the launch-day checklist is the hub. For the bigger picture on how the iOS app fits next to the desktop workbench and AltosDroid, see AltosUI on iPhone: what it is (and what it isn’t).

One reminder on licensing

To legally operate an Altus Metrum flight computer in the US, you need at least a Technician-class amateur radio license. The canonical page is altusmetrum.org/Radio, and the ARRL licensing page is the best place to start if you don’t already hold one.