H just flew away ?

[DoomMeister]

I took a look at the 00056 flightlog which I cut down to the area of arming the motors to the end of recorded telemetry from the aircraft. Comparing inputs on the controller to aircraft response I never saw a loss of RC control. Each change in stick inputs or fight mode showed up in telemetry with the exception near the end when RTH was activated and the aircraft did not switch out of angle mode. This may be because the aircraft was in Angle mode without GPS and RTH requires GPS.

The following graphs show the aircraft reaction to the stick inputs and the changes in flight mode from 21 (Follow Me), to 3 (Angle), to 4 (Angle w/o GPS).

CH10 is the Landing Gear switch (0 is up and 4095 is down), CH4 is the Mode Switch (Smart-3412, Angle-2048, RTH-683), and CH5 is RTH (0-off, 4095-on)

 

[wrench567]

Doommeister.
So what it shows is an operator error? I still don't understand why it stopped and shot left. Letting go of the sticks should have stopped it but didn't. I guess I need to study the graphs after learning how to read them. Why no RF warning when it was plain as day on the screen with the GPS warning? Could it have been when it ducked behind the houses? The other times the GPS failed I was able to control it perfectly. Why not this time? Why the GPS failure to begin with? The hitting of the RTH switch was last ditch effort after it was out of sight. I thought it would at least go to the programed 130 feet so I could see it.
Thank you for your help.
Pete.
P.S. I was unable to try to retrieve it today. I totally forgot my Doctor appointment in Boston. Most of my day was sitting in traffic.

 

[WTFDproject]

Doommeister.
So what it shows is an operator error? I still don't understand why it stopped and shot left. Letting go of the sticks should have stopped it but didn't. I guess I need to study the graphs after learning how to read them. Why no RF warning when it was plain as day on the screen with the GPS warning? Could it have been when it ducked behind the houses? The other times the GPS failed I was able to control it perfectly. Why not this time? Why the GPS failure to begin with? The hitting of the RTH switch was last ditch effort after it was out of sight. I thought it would at least go to the programed 130 feet so I could see it.
Thank you for your help.
Pete.
P.S. I was unable to try to retrieve it today. I totally forgot my Doctor appointment in Boston. Most of my day was sitting in traffic.

There are several things not yet understood. But one that might be explained is the "why it stopped and shot left. Letting go of the sticks should have stopped it but didn't.". When the GPS is not helping control the drone, you have to fly manually, which basically means the compensation for wind is up to the pilot. With no GPS, letting go of the sticks will only stop the drone if there is no wind. Rapid changes in speed, direction and altitude can happen with no input from the controller because the wind is in control. Was there was any wind at the time?
I am unsure of how the flight controller uses GPS. What the logs show is that the GPS unit itself was working, and the Drone's memory knew where it was. But the logs also show that while the GPS information was there, the flight controller was not using it for navigation. I could suspect that recording of the GPS data and using the GPS data for navigation are different parts of the flight controller, but I just don't know for sure. Maybe @h-elsner can provide a better explanation for that.

 

[DoomMeister]

Pete,

I need to take a look at weather for that day to see if wind explains the directional change when GPS dropped and it switched to Angle w/o GPS (mode 4).

Another thing to be aware of is that heights, distances, and speeds are in meters and meters/sec so the altitudes you see in the graphs are about 3.1 times higher than if it was feet instead of meters.

I will investigate more sometime today.

 

[h-elsner]

I agree, the drone all the time followed the commands of the ST16 output. At 12:40:44.5 the flight mode changes to mode 4, GPS off. There is no idication why this happens. Position was in the middle of Oyster Pond. I don't know if the are ships there big (or expensive) enough to have RADAR on board. This may a reason for letting GPS know that it is too bad. The are small changes in accuracy at this time.

After this event the pilot managed it to bring the drone back (1) to the place it started before ( distance to start position ~0 at 12:41:50). But somehow after that things go wrong. The speed increases without stick input up to 10m/s (2). Also here I could not find a reason for. Strange behaviour!

Picture is from the last part of the flight.

Then, after some seconds, the pilot tries to catch it but without success (3). However, the drone followed again those actions. I know that flying without GPS will get very hard if the drone goes fast and is already far away. I thin it made autolanding but on the wrong place.

Electronics needs to be dry and clean before you switch it on again but there is no reason why it should not work.

br HE

 

[wrench567]

Thank you guys.
I was unsuccessful in retrieving the H today. I spoke to the property owner. Very nice lady BTW. She said it went back and forth over the house before slowly landing high in the tree. Then it beeped for what seemed like hours. The only light was a red flashing light that she could see. We have a tropical storm coming tonight with 50 to 60 mph winds and they are forecasting 2 - 4 inches of rain per hour.
There was little to no wind that day. No large boats, but some smaller boats have radar. Especially the sport fishing boats. I did not see any in the pond. The loss of GPS has occurred 4 or 5 times before and I had thought it was fixed by glueing the GPS enclosure solidly. It did five or more flights without issue.
None of my helicopters have GPS and I do occasionally practice loss of orientation with my 450 heli. I also practice it on the Sim. Loss of orientation was the number one cause of most of my early crashes. I almost gave up the hobby until a friend of mine introduced me to the Sim. Controlling the drift, orientation, and gusty winds on the Sim has cut down my crashes to almost none. There are still the occasional mechanical or electronic malfunction.
The first time it lost GPS the H was about 10 feet above the water. I was able to control it without issue. Another time was in a large grass field. And another at the kids playground. The randomness is troubling.
Thanks for your help.
Pete.

 

[DoomMeister]

Pete,

Your last post brought up something that has me curious about your aircraft. You mentioned and issue with gluing the GPS enclosure. Has there been a modification done to the aircraft?

There was also a message I got from another member wondering if there could be an issue with the flight controller on your aircraft. This got me looking at some other columns in the telemetry, specifically the IMU Status column. It shows a drop of components that seem a bit unusual and may indeed point to a problem with the Flight Controller in the aircraft. a bad connection with the GPS board, or both. At 12;40;44 you experienced the loss of GPS and the IMU Status vale went from 225 to 65 which indicates the loss of Controller GPS, GPS2 (the one on the top of the drone), and Sonar leaving just the Controller Compass and the IMU. If it is the F/C it may just need to be removed and reseated a couple of times to remove a fine oxidation on the connections. The GPS/Compass2 board in the top of the drone may need the connections checked also.




Hopefully you will be able to retrieve the aircraft soon and a repair process can be accomplished.

From looking at the kml file in Google Earth Pro it appears you had some control of the craft while it was still over the water, but once it got near you in the parking lot it seemed to be carried away in the direction of the wind. It was responding to controls but they did not appear to overcome the gentle 6 MPH SE wind. With you being an RC helo pilot I have to believe you are used to countering effects of the wind. Hopefully we can find a cause and solution once recovery happens.

 

[wrench567]

I had an earlier thread about the GPS. Yes the H has been modified to put the GPS/ compass on top of the shell. The double stick tape didn't hold it very good so I had redone the mounting. Like I said earlier, I thought it was fixed but I guess not.
The first time it happened. The winds were much stronger. Gusts to 20 to 25 mph.
Thank you for all your help.

 

[dronefisher]

Unbelievable. It's in a tree about 35 feet. My 5 year old grandson spotted it. It looks to be intact. I don't know how to retrieve it. The owner of the property was not home and I didn't want to trudge through fifteen feet of thick brush and brier patch to reach the tree.
Thank God it didn't cause any damage. And thank you for the location. Quite a bit farther than I thought it was.
Pete.

So glad this story has a happy ending. This community is so full of kind geniuses. Make sure you buy your grandson some ice cream or a toy of his choice!

 

[wrench567]

So glad this story has a happy ending. This community is so full of kind geniuses. Make sure you buy your grandson some ice cream or a toy of his choice!

My grandson is not really an ice cream lover. He opted for a large Hershey bar and a package of chocolate chip cookies. That should hold him for awhile.
Yes the people on this forum are tremendously helpful. This is an invaluable resource for us who are not as knowledgeable as I should be. This forum was one of the consideration for me to look at Yuneec. I was also looking into the Autel Evo2. I decided on the H because most of the time the wind is not kind to smaller 4 motor drones. Most days the wind is gusty and changes in an instant.
Thank you.
Pete.

 

[AH-1G]

My grandson is not really an ice cream lover. He opted for a large Hershey bar and a package of chocolate chip cookies. That should hold him for awhile.
Yes the people on this forum are tremendously helpful. This is an invaluable resource for us who are not as knowledgeable as I should be. This forum was one of the consideration for me to look at Yuneec. I was also looking into the Autel Evo2. I decided on the H because most of the time the wind is not kind to smaller 4 motor drones. Most days the wind is gusty and changes in an instant.
Thank you.
Pete.

PM'ed you

 

[Memphis919]

Sad day.
Charged up the 3 flight batteries and ST16. Found a nice little inlet to fly over. First battery and flying great. Voltage read 14.8 so I decided to bring it back. All of a sudden got the GPS warning fly in manual mode. It was already in angle mode. Then got a loss of RF warning and the H took off towards the residential area until I lost sight of it. No control input from me did anything. Right before I lost sight of it the low battery land immediately came on the screen in red. I still had no control.
The loss of GPS happened several times before but not in the past dozen or so flights. I've always been able to control it.
I drove around the neighborhood and walked around a bit. Then went to the police station and reported it lost. I'm heart broken. Hobby dollars are in short supply to replace it. Telemetry shows nothing after GPS loss.
That's it for me for awhile. Thanks for your help and advice I have received these past few months. I have some thinking to do.
Pete.

**** Pete. I'm a new H pilot and I would be just heart broken if that happened to me. I'm truly sorry bro.

 

[dronefisher]

My grandson is not really an ice cream lover. He opted for a large Hershey bar and a package of chocolate chip cookies. That should hold him for awhile.
Yes the people on this forum are tremendously helpful. This is an invaluable resource for us who are not as knowledgeable as I should be. This forum was one of the consideration for me to look at Yuneec. I was also looking into the Autel Evo2. I decided on the H because most of the time the wind is not kind to smaller 4 motor drones. Most days the wind is gusty and changes in an instant.
Thank you.
Pete.

The people on this forum are half the reason I would buy another Yuneec instead of a smaller, non-niche one that uses modern day technology.

 

[Rubik]

Yes, the experts on this forum are amazing!
I had an erratic behaving TH that barely escaped a crash. Replacing the flight controller fixed the problem.

 

[wrench567]

No luck. It would appear that the tree is impervious to 50 to 60 mph winds. The H is still just out of reach. I talked to an arborist about climbing and retrieving it. He's quite busy right now but he has my number. He said no problem and it shouldn't cost too much. He had a good laugh when I told him my grandson charged me a large Hershey bar and a package of chocolate chip cookies for finding it.
To be continued.
Pete.

 

[Mikieh]

Sad day.
Charged up the 3 flight batteries and ST16. Found a nice little inlet to fly over. First battery and flying great. Voltage read 14.8 so I decided to bring it back. All of a sudden got the GPS warning fly in manual mode. It was already in angle mode. Then got a loss of RF warning and the H took off towards the residential area until I lost sight of it. No control input from me did anything. Right before I lost sight of it the low battery land immediately came on the screen in red. I still had no control.
The loss of GPS happened several times before but not in the past dozen or so flights. I've always been able to control it.
I drove around the neighborhood and walked around a bit. Then went to the police station and reported it lost. I'm heart broken. Hobby dollars are in short supply to replace it. Telemetry shows nothing after GPS loss.
That's it for me for awhile. Thanks for your help and advice I have received these past few months. I have some thinking to do.
Pete.

You are one of the lucky ones. I lost my H Pro in the forest and could never find it. I decided to use a “range extender” for the first time and quickly lost signal with a rapid descent to follow. 3 safaris into the woods and no luck. As Charlie Brown would say”AAAAARGHHH!!!

 

[wrench567]

You are one of the lucky ones. I lost my H Pro in the forest and could never find it. I decided to use a “range extender” for the first time and quickly lost signal with a rapid descent to follow. 3 safaris into the woods and no luck. As Charlie Brown would say”AAAAARGHHH!!!

That is so sad. Perhaps you could use an eagle eyed grandson. They not cheap. Have you seen the price of a large Hershey bar? Chocolate chip cookies are rarely on sale.
All kidding aside. I truly feel for you. My biggest fear was someone getting hurt or property damage. That would have been awful.

 

[Fred Garvin]

My biggest fear was someone getting hurt or property damage. That would have been awful.

That's my biggest fear with any type of fy away or loss of control. Drones can be repaired/replaced, but if one of my birds hurt someone, I'd be devastated.

 

[dronefisher]

That's my biggest fear with any type of fy away or loss of control. Drones can be repaired/replaced, but if one of my birds hurt someone, I'd be devastated.

Ten different tragic scenarios ran through my mind during the three seconds it took for my Q500 to fall from the sky. Almost like being behind the wheel when you know you're about to crash. Fortunately, only the drone suffered...

 

[wrench567]

Update.
The H has been recovered. My grandson and I tried again today. It only cost me a large Kit Kat bar this time. I had used 1 inch ID PVC pipe before but the flex of the joints was too much for the connecters. This time some hardwood 1 inch dowels screwed so they straddled the joints stiffened it enough to push it from it's nest. It didn't fall straight down but caught up on lower branches until the final decent to the ground from 12 to 14 feet. It took six 6 foot sections of pipe to dislodged it.
Preliminary going over. One broken prop, all 4 dampers dislodged, missing a foam foot, the aftermarket GPS holder is hanging by the wires, and pine pitch and tree mites all over it. Time to disassemble it.
Thank you to the wizards of the drone world for the location and evaluation of the final flight.
Pete