PX4 ALTA X · 2023-05-29

Flight telemetry summary

Distance Meters

15419.9 m

Maximum Altitude AGL

66.9 m

Maximum Ground Speed

20.3 m/s

Minimum Battery Percent

13.6%

Minimum Battery Voltage

37.12 V

Minimum GPS Satellites

30

Maximum GPS HDOP

0.53

Flight Modes

ALTCTL, POSCTL, AUTO_MISSION, AUTO_LOITER, POSCTL

Maximum Distance From Home Meters

795 m

Maximum Distance From Home Time

32m 51s

Average Ground Speed

7.51 m/s

Maximum Climb Rate MPS

5.97 m/s

Maximum Descent Rate MPS

-3.13 m/s

Battery Consumed MAH

45193.5 mAh

Battery Consumed Wh

1767.25 Wh

Voltage Sag

12.75 V

Flight Mode Seconds

ALTCTL: 13s, POSCTL: 5m 5s, AUTO_MISSION: 32m 27s, AUTO_LOITER: 2s

Maximum GForce

4.1 g

EKF Healthy

Yes

Weather at the flight

Source

open-meteo-archive

Sampled At Utc

2023-05-29T03:00Z

Latitude

-31.79

Longitude

115.87

Temperature C

18.6 °C

Wind Speed MPS

3.8 m/s

Wind Direction Degrees

35

Wind Direction Cardinal

NE

Weather Code

3

Weather Description

Overcast

AI flight report

This flight ran 37:46 and covered 15,420 m, taking the aircraft as far as 795 m from home (reached at 32:51). After takeoff at 0:11 the drone climbed quickly to its ceiling of 67 m above home by 0:45, briefly overshooting slightly before settling to a steady 60 m cruise altitude that it held almost exactly for the entire mission — the telemetry table shows altAGL parked between 59.8 and 60.1 m from roughly 2:00 through 34:00. Ground speed during the mission body was similarly consistent, cycling around 8 m/s with periodic slowdowns (e.g. 6:00, 9:45, 17:45) that look like waypoint turns rather than problems. The one speed spike worth noting is at 1:32, where the drone hit its max ground speed of 20.3 m/s while still in POSCTL, before AUTO_MISSION took over at 1:44. Conditions were mild — 18.6°C, overcast, wind 3.8 m/s from the northeast — nothing here suggests weather was a factor.

Two things stand out as anomalies rather than routine flight. First, at 0:00 the log flags a 20 m disagreement between barometric and fused altitude, and the derived diagnostics show this gap actually peaked at 22.6 m around 19:08 — sustained enough that it's likely a real sensor discrepancy rather than noise, though the data here can't say which source (baro or fused/GPS) was off. Second, and more consequential, the battery sagged hard under load: at 32:51 voltage dropped to 40.3 V from a 49.9 V resting value (0.81 V/cell across 12 cells), and by the end of the flight resting voltage itself had fallen to 37.12 V at 37:01, with the battery critical warning firing at 37:21 and the flight landing at 15% remaining. The descent and landing sequence starting around 34:11 (AUTO_LOITER, then POSCTL at 34:13) also includes the flight's fastest descent, -3.1 m/s at 35:03, dropping from 60 m to 31 m in the space of one 15-second sample — worth a look in the replay to confirm it was a controlled step-down and not something more abrupt, since the table can only show the endpoints, not the path between them.

The clearest actionable item is battery margin: this pack was discharged to 15% and 37.12 V by landing, well past the point where the low-battery (33:47) and critical (37:21) warnings had already fired, and the sag test at 32:51 shows the pack losing nearly 10 V under mission load late in the flight — a sign of a battery that's aging or was pushed close to its limit. Tightening the return-to-land trigger point, or swapping packs earlier in similar-length missions, would build back the margin this flight used up. The altitude-disagreement event at 0:00–19:08 is worth a quick sensor check (barometer calibration or GPS altitude health) before ruling it out as cause for concern.

Detected flight events

1. 0s — Barometric and fused altitude disagree by 20 m

   Barometric and fused altitude disagree by 20 m

2. 11s — Takeoff (altitude threshold)

   Liftoff at 2 m. The aircraft leaves the ground and starts its climb.

3. 13s — Flight mode changed to POSCTL

   Flight mode changed to POSCTL. The pilot or autopilot switched control behavior here.

4. 45s — Maximum altitude: 67 m above home

   Maximum altitude: 67 m above home — the highest point of this flight.

5. 1m 32s — Maximum ground speed: 20.3 m/s

   Maximum ground speed: 20.3 m/s — the fastest the aircraft moved over the ground.

6. 1m 44s — Flight mode changed to AUTO_MISSION

   Flight mode changed to AUTO_MISSION. The pilot or autopilot switched control behavior here.

7. 32m 51s — Battery sagged to 40.3 V from 49.9 V resting (0.81 V/cell across 12 cells)

   Battery sagged to 40.3 V from 49.9 V resting (0.81 V/cell across 12 cells)

8. 33m 47s — Battery below 30%

   Battery below 30%. Battery at 30%. Time to plan the return leg.

9. 34m 11s — Flight mode changed to AUTO_LOITER

   Flight mode changed to AUTO_LOITER. The pilot or autopilot switched control behavior here.

10. 34m 13s — Flight mode changed to POSCTL

    Flight mode changed to POSCTL. The pilot or autopilot switched control behavior here.

11. 37m 21s — Battery below 15%

    Battery below 15%. Battery at 15%. The aircraft should land as soon as possible.