Mini SE VPS malfunction flyaway - help determine where to search?

[skysheen]

I just had the dumbest crash/flyaway thanks to the VPS sensor malfunctioning in midair and preventing me from descending until the battery ran out.

Timeline:

This was my second flight of the night to take photos next to a ~1900ft tall antenna tower. I ascended to the max firmware height (1640ft) and flight was relatively stable aside from some drift due to the high winds. The windsock on the ground showed the wind blowing SW. Upon the battery reaching around 60%, I began to descend straight down but found my descent speed was limited to about 1mph no matter what I did. I switched modes, disconnected, reconnected, closed and reopened the app, initiated RTH, nothing.

The RTH began bringing the drone to the home point before descending further, and the same slow descent issue persisted. There were several minutes of just hopelessly holding max down throttle and not being able to do anything. I turned it into the wind and started to notice the drone drifting horizontally, so I attempted to horizontally move to a safer location near the home point. As time progressed (the UI was already showing 0% battery) it seemed to lose horizontal stability further and drift further out of the area.

Right around the UI showing ~1000ft distance to home and ~1200ft altitude, I completely lost radio contact with the drone after getting the auto power save/forced landing warning.

The photo attached is where I saw the drone's final descent. The azimuth is approximately 260 degrees.

From the home point I saw the aircraft begin a rapid descent with stable attitude and a roughly 30rpm spin. I estimate the final negative vertical speed I saw was ~20mph/1700fpm.

Airdata link to the initial part of the flight (before disconnecting while troubleshooting), includes log file downloads:

Airdata link to final log, includes log file downloads:

I went to the last known location and searched all over but didn't see anything. I also went further to the west, but I suspect I didn't search far enough and by now the firehouse strobes/beepers are probably dead.

I'm going to try searching again in the morning, can anyone help narrow down where to look?

 

[Meta4]

I went to the last known location and searched all over but didn't see anything. I also went further to the west, but I suspect I didn't search far enough and by now the firehouse strobes/beepers are probably dead.

I'm going to try searching again in the morning, can anyone help narrow down where to look?

The last location recorded when power failed was 25.53505 -80.47470.
At that time the drone was descending, but also being flown northwest at 6.7 mph.
From the height the drone fell, it would have taken approx 27 seconds to reach the ground.

The drone's momentum, it could have carried the drone further Northwest.
But wind was also affecting it.
Wind appears to have been from the North, at a speed of maybe 12 mph up high and reducing at lower altitudes.

The combination of an uncertain wind and an approximate estimate of the drone's momentum, makes it difficult to give you an accurate search point.
But the drone should have come down somewhere Southwest of the last recorded location.
Some rough figuring comes up with a place to start looking at around 25.53422 -80.47529 (about 360 ft SSW of the last recorded location) and look a little further SW and on both sides of a line from there to the last recorded location.

 

[skysheen]

Thanks! I searched all the way out to about 2 miles west down the major roadway, but no luck sadly. The fields near the last known position I scanned with binoculars at various points from different corners.

Realistically there's nearly zero chance of recovering it now, unless someone happens to find it and contact me (it's labeled with my phone number.)

Hard lessons learned, and this makes me want to build my own drone with redundant components even more.

 

[GFields]

Thanks! I searched all the way out to about 2 miles west down the major roadway, but no luck sadly. The fields near the last known position I scanned with binoculars at various points from different corners.

Realistically there's nearly zero chance of recovering it now, unless someone happens to find it and contact me (it's labeled with my phone number.)

Hard lessons learned, and this makes me want to build my own drone with redundant components even more.

So sorry for your loss. Hope you had insurance or DJI refresh.

 

[skysheen]

So sorry for your loss. Hope you had insurance or DJI refresh.

Unfortunately not, the drone was *just* cheap enough to not justify it. When I get a higher end model I definitely will. The other lesson learned is I'm going to have a second drone on standby during night flights to help locate the primary drone if it goes down. The irony is it would have been really helpful to have a drone to find my drone LOL