The OnFlight Data Converter converts .onflight recordings into files for spreadsheets, analysis software, and flight review. This manual describes the CSV, Simplified CSV, and MATLAB outputs for Hub and Hub Plus recordings.
Download the OnFlight Data Converter for Windows or macOS.
Convert a recording
- Turn off the Hub before removing its microSD card. Copy the
.onflightfile to a folder on your computer. - Open the converter and choose Select File To Convert.
- The converter displays information about the recording. Packets Found shows the number of recorded samples available for conversion.
- Review Pilot Name, Tail Number, and Aircraft Type. These are filled from the recording when available; you can edit them before conversion.
- Select an Output Format and choose Convert.
- When conversion finishes, use the path shown under File Saved As to locate the output.
Outputs are saved beside the input file. Converting again to the same format replaces that output file. Keep the original .onflight recording so you can export another format later.
Choose an output
| Menu option | Output for flight.onflight |
Use |
|---|---|---|
| Full CSV | flight_full.csv |
Sensor measurements, navigation results, and sensor status for analysis and troubleshooting. |
| Simplified CSV | flight_simple.csv |
A smaller set of flight parameters, with optional sensor columns included when detected in the recording. |
| MAT | flight.mat |
Recorded measurements and status information for analysis in MATLAB. |
The converter also offers CloudAhoy and compatible OnFlight export versions. For uploading flights to review services, see Recording and export.
Understand the data
The exported data includes the recording from startup onward. Each row represents one recorded sample. Some sensors update less often than others, so their values may repeat across several rows.
Measurements are shown in the units listed in this manual. Status fields show whether the navigation system has finished starting, whether sensors are connected, and whether they report normal operation. Use these alongside the measurements, especially during startup or when an optional sensor was disconnected.
Some columns may be present even when no data was recorded for them. A zero value does not necessarily mean a measured value of zero.
Coordinates and units
Aircraft axes are X forward, Y right, and Z down when the mounting and configured rotation align the Hub with the aircraft. Positive rotation means rolling right, pitching nose-up, or yawing right. North, east, and down velocities describe movement in those directions.
The inertial navigation system (INS) combines motion-sensor and satellite measurements to estimate aircraft attitude, speed, and position. GNSS refers to the satellite navigation receiver. Full CSV includes both individual sensor measurements and the INS results.
| Quantity | Convention |
|---|---|
| Acceleration and load factor | G denotes multiples of standard gravity. |
| Angular measurements | Degrees; angular rates are degrees per second. Magnetic variation is positive east. |
| Position | Latitude and longitude in decimal degrees. |
| WGS84 altitude | Height above the WGS84 ellipsoid, feet. |
| MSL altitude | Height above mean sea level, calculated as WGS84 altitude minus GNSS geoid height. |
| Pressure altitude | Altitude derived from pressure; cabin and external air-data values are separate. |
| AGL altitude | Height reported by the external above-ground-level sensor, feet. |
| Pressure | Pascals. |
| Speed | Knots; climb rate is feet per minute. |
| Temperature | Degrees Celsius. Die temperatures describe the electronics, not outside air temperature. |
| Magnetic field | Microteslas (uT). |
Time information
System time is elapsed time since the Hub was turned on, in seconds. UTC is the calendar date and time. Hub Plus also provides GPS time of week (TOW), in seconds, together with the GPS week number.
| Time field | Hub | Hub Plus |
|---|---|---|
| System time | Millisecond resolution (0.001 s). | Microsecond resolution (0.000001 s). |
| UTC seconds | Whole seconds. | Microsecond resolution (0.000001 s). |
| GPS time of week | Not included in the .onflight recording. |
Microsecond resolution (0.000001 s). |
Hub records UTC fields directly from its GPS receiver. Those values update with receiver data and can repeat across recorded samples.
Hub Plus synchronizes its clock to the GPS receiver’s one-pulse-per-second (PPS) signal. Between these one-second pulses, it uses its internal clock to timestamp the higher-rate samples. Both UTC and GPS time of week use this synchronized clock. Check the UTC and GPS time initialization fields to see when those time references are available. Resolution describes the recorded time increments, not a guarantee of absolute timing accuracy.
These UTC fields are separate from the microSD file’s creation and modification timestamps. The configurable UTC offset affects those file timestamps, not the UTC data exported here.