Maximum Motor Speed Reached Warning

[Telemarker]

OK, so I am new to drone flying (and very new to this Forum!).

This morning, I decided to fly my Phantom 3SE out of my garden (in NW England) over the field behind, to see if I could get above the ice fog to view the winter landscape around me. The temperature was -4C, and the fog seemed to be no higher than a few 10s of metres (I could see blue sky above me). I decided to keep it simple: auto-takeoff, climb to about 50m altitude, rotate to capture 4k video, then auto-land. The battery I was using had (reportedly) 80% charge, and I had kept the drone, its controller, and all batteries in my centrally heated house all night. I chose a low interference 5 GHz channel, and I also did a compass re-calibration before taking off.

However, when the drone had reached no more than 30m and was hovering stationary , I got a 'Maximum Motor Speed Reached' warning, that I had never seen before. Almost immediately the drone seemed to lose stability and plummeted, then crash-landed in the field behind my garden. Fortunately, no damage was done - the drone was attempting to regain control all the way down, and I had the rotor protectors installed.

It is not clear to me whether this was cause by icing up (it didn't seem to be after recovery), or the aftermarket battery I was using was quickly and adversely affected by the cold.

Has anyone else had this experience?
What is the coldest you have flown (a Phantom 3) in?
Any advise in avoiding this problem?

Thanks.

 

[MotorCycle-Man]

Thats a very strange warning i must agree and i have never heard of it here on this PP forum till i read of your issue... and i know this....1 never fly with a battery that's less then fully charged !
2 IF.....your going to fly in very cold temps...and a manuel take off....rise to say 5 feet and houver for a few minutes
to fully warm the battery for more..then proceed with the flight carefully.

I'm watching for some replies and i know for sure....your going to be asked to post the flight record so you might as well
do that and post them.....!

 

[3rdof5]

Agreed with motorcycle man, and I've never heard of that error either but it does suggest the props were icing and losing lift and the AC tried to compensate by increasing motor speed to max.

 

[Forgotten_Fox]

Motor overspeed means a motor has reached its max allowed rpm. The phantom holds position by increasing and decreasing power to its motors. If something causes a motor to max out its rpm, when the phantom needs to apply more power to it to remain stable, the motor won’t increase speed, leading to the unstable flight you described. Likely causes of overspeed are usually high winds, but in your case, temps combined with a partial battery are likely to blame.

 

[Fly Dawg]

It is not clear to me whether this was cause by icing up (it didn't seem to be after recovery), or the aftermarket battery I was using was quickly and adversely affected by the cold.

It is possible to determine a battery issue with the aircraft .dat log file. However, since the P3SE logs do not report motor rpm, it would be difficult to determine a motor issue. Might be worth looking though, if you want a better answer.

 

[Telemarker]

It is possible to determine a battery issue with the aircraft .dat log file. However, since the P3SE logs do not report motor rpm, it would be difficult to determine a motor issue. Might be worth looking though, if you want a better answer.

Where would I find the .dat log file, and how would I access it?

 

[Telemarker]

On the battery issue: the app reported that the battery was on 80% on take-off and about 50% after crashing - the vehicle was only the air about 1-2 minutes. But I wondered if the cheaper (non DJI) battery lost voltage quicker because of the cold, even though it was reporting adequate charge.

 

[Aussie Paul]

Could prop icing reduce efficiency so the motors had to spin faster trying to maintain altitude?

Aussie Paul.

 

[With The Birds]

On the battery issue: the app reported that the battery was on 80% on take-off and about 50% after crashing - the vehicle was only the air about 1-2 minutes. But I wondered if the cheaper (non DJI) battery lost voltage quicker because of the cold, even though it was reporting adequate charge.

Looking at the flight log will be helpful. Usable capacity ordinarily will relate to the entire pack (all cells series connected) however if one cell
Is low in voltage it will be the determining factor. You aren’t the first to ignore the suggestion to not fly with a partially discharged battery. Unfortunately you aren’t the first to suffer the consequences either.

 

[Fly Dawg]

Where would I find the .dat log file, and how would I access it?

See this link. These files are usually very large and is difficult at times to pick the right one for the flight in question. If you need assisstance with this you will need to extract the file then upload to a sharable location such as Dropbox, Google Drive...etc.....and share a link back here to that.

Retrieve Dat File

 

[Telemarker]

Thanks, will try that.

 

[Telemarker]

Some years ago we did a study at work on the effects of icing on fixed wing aircraft.
One obvious mitigation is applying deicing fluid to the wings, but I am not sure this would persist long enough to work on the Phantom 3 props.

However, as a cross-country skier, I regularly apply various wax and Teflon compounds to the glide zones to prevent icing ('balling up', we call it). Since the Phantom props are made out of a similar material to ski bases, I may try this. I will report back whether this presents a problem for 'normal' flight, and whether it prevents the issues I had above on an 'abnormal' flight (if I get another foggy day!).

 

[PhantomWetSuits]

OK, so I am new to drone flying (and very new to this Forum!).

This morning, I decided to fly my Phantom 3SE out of my garden (in NW England) over the field behind, to see if I could get above the ice fog to view the winter landscape around me. The temperature was -4C, and the fog seemed to be no higher than a few 10s of metres (I could see blue sky above me). I decided to keep it simple: auto-takeoff, climb to about 50m altitude, rotate to capture 4k video, then auto-land. The battery I was using had (reportedly) 80% charge, and I had kept the drone, its controller, and all batteries in my centrally heated house all night. I chose a low interference 5 GHz channel, and I also did a compass re-calibration before taking off.

However, when the drone had reached no more than 30m and was hovering stationary , I got a 'Maximum Motor Speed Reached' warning, that I had never seen before. Almost immediately the drone seemed to lose stability and plummeted, then crash-landed in the field behind my garden. Fortunately, no damage was done - the drone was attempting to regain control all the way down, and I had the rotor protectors installed.

It is not clear to me whether this was cause by icing up (it didn't seem to be after recovery), or the aftermarket battery I was using was quickly and adversely affected by the cold.

Has anyone else had this experience?
What is the coldest you have flown (a Phantom 3) in?
Any advise in avoiding this problem?

Thanks.

I have gotten this Maximum Motor Speed Reached when going vertical at top speed trying to cut thu the wind.

So I think that is normal , but when it needed to boost the motors the battery gave out as the vertical climb just was to much in that Cold, and I think the battery gave out.

When we do fly in the Extreme Temps its never in Sport mode and we stay away from Vertical climbs because of that warning.

That combination is a dangerous one not to mention how cold it was at that height.

Phantomrain.org
Approved Vendor.

 

[Andy9]

I've got once the warning of 'the motor has not enough power' or something like that.
I think that this was because my friend, using my drone, started with only 50% of battery lifting it directly up. Maybe the motor didn't get the required voltage from the battery. But no issues after that. It's a kind of the opposite warning as we have here.

 

[With The Birds]

What are you trying to demonstrate here? Which part of the body was the prop interrogating with. Can you post an image of the damage?

 

[Telemarker]

See this link. These files are usually very large and is difficult at times to pick the right one for the flight in question. If you need assisstance with this you will need to extract the file then upload to a sharable location such as Dropbox, Google Drive...etc.....and share a link back here to that.

Retrieve Dat File

That link didn't make much sense for MacOS, and my MacBook wouldn't talk directly to the Phantom 3 SE vehicle, via the USB link. However, I did manage to find some flight logs on my iPhone7 (used as the controller). There were: CSV files, which just listed the lat, long and battery charge at each time interval; there were .dat files which just contained flight notifications and warnings; and finally there were .txt file which just displayed as gobble-di-gook in my text editor. The CSV files for the 2 flights in the fog, give no information as to what happened - the battery charge remained around 50-60% in both cases, not showing any sudden discontinuities, and the lat-longs showed the vehicle hovering above my garden, then spiralling downwards.

A week later, I flew the Phantom 3 above a friend's farm, in similar temperature conditions (-3C) but with no fog - just sunny with clear blue sky. The vehicle performed faultlessly, burning through 2 fully-charged batteries (down to about 20% in both cases) - getting about 30 minutes of flight in total. This has convinced me the issue was icing in the fog.

 

[Telemarker]

What are you trying to demonstrate here? Which part of the body was the prop interrogating with. Can you post an image of the damage?

No damage, I have flown the vehicle successfully since the crash in the fog.

 

[Fly Dawg]

I did manage to find some flight logs on my iPhone7 (used as the controller). There were: CSV files, which just listed the lat, long and battery charge at each time interval; there were .dat files which just contained flight notifications and warnings; and finally there were .txt file which just displayed as gobble-di-gook in my text editor. The CSV files for the 2 flights in the fog, give no information as to what happened

The SE does not report motor data in the aircraft .dat file. So that will not help. The .csv files from the device won't either. You need to see the AC file for additional data. That is why I posted the link. I don't use a Mac so can't help you there, but many others have had no issues getting the files with Apple devices.

 

[hsp]

Why flies in foggy weather temperature under zero if not serous businesses payee photo jobs.
If you fly in low attitude and no wind you can still fly down to 3-5% if battery has same voltage on all cells and fresh and quick take charge.
Warm up battery inside a jacket before if it under 10 Celsius.
Some after market batteries has not good quality.
I have bay to several issues as laptop camera only before USB battery pack be on market.
But for reason to crash drone by only DJI battery from serious dealer.
Better take down drone and have recharge it from inverter or some device if you have car in short distance.