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MA2 forced landed at 12% battery and communication was lost because of elevation change.

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JohnNokomis

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I need to know how the MA2 acts when in RTH mode and forced land mode simultaneously. I knew I wasn't making it back home during this flight, and I had a rough idea where I was going to crash land and go retrieve the drone. I had picked the 4 way stop just to the bottom left of the picture. I never expected it to force land at 12% battery...? As soon as that happened I lost all contact. I'm attaching an image and would like anyone's idea on what the estimated trajectory would be from this point. It was still 319 feet off the ground with 10% battery at last contact. I went and searched where the DJI fly app told me to (which was directly under the end of the red line) but it was already dark and none of this is my land. I drove all around the area and the RC never made contact. Thank you for any input.MA2 Crash Path.jpg
 
Were you pushing your LEFT control stick UP (mode 2) constantly as you were bringing the drone back home? You had 10% batt remaining and would have made it another several hundred feet at least with that amount of charge remaining. Compounding your problem was the 7 mph headwind on your return leg, and nearly a 4 mile round-trip distance, as well as flying in near-dark conditions at sunset. You should be able to tell what direction the wind is blowing from before launching. If there is a significant wind, don't fly away with the wind - fly into the wind and see how that affects the drone's speed. If there is enough wind to make flying against the wind difficult, do not fly downwind. It might be slow flying upwind, but the return flight will be easy. Ask that farmer if you can go look on his land to locate it, or use another drone to search for it at a safe altitude.
 
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It's likely that the RC never reconnected because the aircraft had landed and shut down. The continuous progress back towards the home point was due to a combination of RTH and stick inputs:

Battery.png


Once the aircraft lost connection it will have autolanded vertically, and so the landing point should be directly under the last recorded position, to within 20 m or so:

grab39.jpg
 
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I need to know how the MA2 acts when in RTH mode and forced land mode simultaneously.
This flight was never going to end well.
You made two fatal mistakes.
1. You flew away in the direction of the wind, which meant that the return flight would be against a headwind.
2. You flew much too high, where the wind was much stronger than at ground level, and left the drone up there for most of the return flight, needlessly wasting battery fighting a strong headwind.

You launched, flew high and went a long way out, flying north with the strong southerly wind.
The drone had to pitch 27° just to hold position when it was hovering.
You started to fly back home when the battery reached 64%, but at full stick the drone could only make 5-6 mph pushing against the wind.

At 9:25.2 (50% battery, you gave up and initiated RTH, with the drone still up way too high and exposed to the strong hhigh level wind.
At 10:17.5 (42%) you started bring the drone down, but only slowly.
As the altitude became lower, the drone's speed increased, but the battery level was very low.

At 12:40 (21%) you stopped descending - the drone was still >500 ft up.
At 13:52.6 (12%) and still 9300 ft out and 520 ft up, the following warning showed:
Critical low battery. Aircraft landing automatically (Code: 30033).

At 14:16 contact was lost.
The drone was still 9000 ft away from home and 312 ft up.

Because the drone was in Critical Low Voltage autodescent, the only thing it will have done after losing signal would be to continue descending at about 10 ft/sec.

The last location was 34.36133 -86.5314 and the search point should be around there
 
Were you pushing your LEFT control stick UP (mode 2) constantly as you were bringing the drone back home? You had 10% batt remaining and would have made it another several hundred feet at least with that amount of charge remaining.
No he wasn't, but fighting against the autolanding would have only burnt more battery.
A few hundred feet wouldn't have helped enough to make any difference since the drone came down 1.7 miles away from home.
 
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This flight was never going to end well.
You made two fatal mistakes.
1. You flew away in the direction of the wind, which meant that the return flight would be against a headwind.
2. You flew much too high, where the wind was much stronger than at ground level, and left the drone up there for most of the return flight, needlessly wasting battery fighting a strong headwind.

You launched, flew high and went a long way out, flying north with the strong southerly wind.
The drone had to pitch 27° just to hold position when it was hovering.
You started to fly back home when the battery reached 64%, but at full stick the drone could only make 5-6 mph pushing against the wind.

At 9:25.2 (50% battery, you gave up and initiated RTH, with the drone still up way too high and exposed to the strong hhigh level wind.
At 10:17.5 (42%) you started bring the drone down, but only slowly.
As the altitude became lower, the drone's speed increased, but the battery level was very low.

At 12:40 (21%) you stopped descending - the drone was still >500 ft up.
At 13:52.6 (12%) and still 9300 ft out and 520 ft up, the following warning showed:
Critical low battery. Aircraft landing automatically (Code: 30033).

At 14:16 contact was lost.
The drone was still 9000 ft away from home and 312 ft up.

Because the drone was in Critical Low Voltage autodescent, the only thing it will have done after losing signal would be to continue descending at about 10 ft/sec.

The last location was 34.36133 -86.5314 and the search point should be around there

Wow ... flying almost 3 miles downwind in a strong wind. Not a good decision.
 
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Yeah, I figured as much. More realistically I thought he could have gotten it closer to the main road to the east so it would have been easier to see and retrieve. You know, that whole situational awareness thing we pilots love to talk about! I’ve had two forced landings since I started flying drones back in September, but both times I was able to put it where I could get at it after it landed. My first forced landing I didn’t realize I could even force up the elevation control to keep it from landing and I was only 400 feet from home with 10% remaining, so lesson learned there. The second one I miscalculated the wind above 100 feet as it was significantly higher, as my flight speed had dropped to 1 to 3 mph at only 200 feet altitude. I hadn’t felt that helpless since trying to fly out of a mountain wave over the Cascade Mountains up in Washington state with my 200 HP Piper Arrow. I usually NEVER make the same mistake twice and I’m here to learn as much as possible from other people’s challenges. FLYING Magazine had an article called “I Learned About Flying From That” and I read every one of those articles for decades from the luxury of my recliner, which is waaaayyyy better than that pucker feeling at 10,000 feet! Thanks for replying to my post, Meta4.
 
Did this "pilot" pay any attention to FAA restrictions on height or VLOS? Doesn't seem like it. Stuff like this is what gives our activity a bad name at best, and can lead to further restrictions at worst. Am I missing something here?

Seems the OP considers forced landings to be normal operation? Do others feel this way?
 
Did this "pilot" pay any attention to FAA restrictions on height or VLOS? Doesn't seem like it. Stuff like this is what gives our activity a bad name at best, and can lead to further restrictions at worst. Am I missing something here?

Seems the OP considers forced landings to be normal operation? Do others feel this way?
Yes Karen I payed attention to the laws. (Mod Removed Political Remark)It's online drone police like you that give our hobby a bad name. As you can see I am flying over nothing but fields and pastures. No I don't consider forced landings normal operations. Did you even read my post? I'm frustrated that the fact that it initiated when I still had 12% battery and was on course for a known LZ. Instead it took control and I have no idea where it choose as an LZ. I'd rather it had flown until it dropped out of the sky than it think it knows better than I. We had a heavy storm come through a few hours later so the drone is probably toast now anyways.
 
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Yes Karen I payed attention to the laws. Mod Removed Political Remark)It's online drone police like you that give our hobby a bad name. As you can see I am flying over nothing but fields and pastures. No I don't consider forced landings normal operations. Did you even read my post? I'm frustrated that the fact that it initiated when I still had 12% battery and was on course for a known LZ. Instead it took control and I have no idea where it choose as an LZ. I'd rather it had flown until it dropped out of the sky than it think it knows better than I. We had a heavy storm come through a few hours later so the drone is probably toast now anyways.
Firstly, no, it's not someone pointing out that you flagrantly broke the law that gives the hobby a bad name - it's people like you who break the law who do that, all by yourselves.

Secondly, your complete lack of understanding of the DJI smart battery RTH and autoland system is entirely your problem. As you can see from the graph I put in post #4, the autoland battery percentage is a simple function of altitude, and is designed to get the aircraft back on the ground without either running out of battery entirely and falling from the sky or running the battery low enough to cause damage.

Lastly - leave the ad homs and your political inclinations out of your posts if you don't want them deleted.
 
Firstly, no, it's not someone pointing out that you flagrantly broke the law that gives the hobby a bad name - it's people like you who break the law who do that, all by yourselves.

Secondly, your complete lack of understanding of the DJI smart battery RTH and autoland system is entirely your problem. As you can see from the graph I put in post #4, the autoland battery percentage is a simple function of altitude, and is designed to get the aircraft back on the ground without either running out of battery entirely and falling from the sky or running the battery low enough to cause damage.

Lastly - leave the ad homs and your political inclinations out of your posts if you don't want them deleted.
 
Ok guys being as John here decided not to take my advise
and started another thread which I had to delete he asked for
his account to be deleted so he’s gone and really see no need
for this to stay open.
🤷‍♂️
CLOSED​
 
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