H 480 Won't descend.

[KEITH KUHN]

Long story short
I took my typhoon H out in the backyard everything was charged and calibrated. I flew an angle mode. I was bringing it back way
Before the first battery warning .
Hovering at 20 to 25 Left Stick
Down for 20 seconds, Drone will
not decend . After what seemed to be an eternity I finally got it low
Enough and close enough to
Hand catch it. Phewww. Tomorrow is another day.. all comments welcome. Keith Kuhn

 

[rdonson]

Perhaps if you shared your telemetry files for this flight someone would be able to see what happened.

By any chance does this H 480 have RealSense that was active?

 

[KEITH KUHN]

Perhaps if you shared your telemetry files for this flight someone would be able to see what happened.

By any chance does this H 480 have RealSense that was active?

This one does not have a real sense module on it. In a few days perhaps I can get the Telemetry files out.
Thanks for your reply Keith Kuhn

 

[Dustoff]

Mine did this once for no apparent reason , I used the stop start button bumping trick to bring it back down . the thing I did not try was to hit the return to home but it will probably scare you if it rises up a little before coming down.


I never could figure out why but afterwards i did a complete accelerometer calibration and compass

 

[KEITH KUHN]

Mine did this once for no apparent reason , I used the stop start button bumping trick to bring it back down . the thing I did not try was to hit the return to home but it will probably scare you if it rises up a little before coming down.


I never could figure out why but afterwards i did a complete accelerometer calibration and compass

Mine did exactly what yours did.
I did the red button bump as you did..
Mine rose up as well. I almost started to take it out of the GPS mode but
Chose not to. I am going to do a lot
Of looking into it before I Fly again.
Keith Kuhn

 

[AeroJ]

Yes mine has done this on one occasion as well. I wouldn't say that makes it untrustworthy though - it is quite a rare occurrence, and eminently solvable - you just have to know how to deal with it when it happens. The key is not to panic, but I accept that is difficult not to do the first time this happens, especially if you were unaware it was a possibility... I certainly panicked initially, and that very much didn't help

There are several things you can do reported to work at one time or another...

1. Climb to about 100 ft and try coming down again. Repeat and see if it lets you descend past the invisible 'barrier'.
2. Cycle the landing gear.
3. Hold the throttle at minimum, and sometimes the craft will inch its way to the ground very slowly
4. RTH - this worked for me, but check you have GPS active and working before you call this Mode, and enough battery to handle a fast rise, and don't do it if there is any doubt about that.
5. Red button short presses (1 ft drop) are the most extreme solution, but tend to work every time.

When I contacted Yuneec tech support (UK) about this they reacted as if it was the first time they had heard of such a thing, and were unable to offer any speculation about why it happened without the telemetry. I was within warranty, and they offered to take a look for me, but instead I chose to monitor the situation, and haven't had a single repeat of it since the initial episode.

 

[didouglog]

Idem for me it stayed is 50 cms ground impossible to come down
Personally I makes a calibration accelerometer before every flight and every battery and no more problem

 

[B Scott]

I replaced my last TH because it would not decend properly. My solution was to activate home mode

 

[didouglog]

whith my old naza v2 dji on tarot hexa never problem

 

[KEITH KUHN]

Yes mine has done this on one occasion as well. I wouldn't say that makes it untrustworthy though - it is quite a rare occurrence, and eminently solvable - you just have to know how to deal with it when it happens. The key is not to panic, but I accept that is difficult not to do the first time this happens, especially if you were unaware it was a possibility... I certainly panicked initially, and that very much didn't help

There are several things you can do reported to work at one time or another...

1. Climb to about 100 ft and try coming down again. Repeat and see if it lets you descend past the invisible 'barrier'.
2. Cycle the landing gear.
3. Hold the throttle at minimum, and sometimes the craft will inch its way to the ground very slowly
4. RTH - this worked for me, but check you have GPS active and working before you call this Mode, and enough battery to handle a fast rise, and don't do it if there is any doubt about that.
5. Red button short presses (1 ft drop) are the most extreme solution, but tend to work every time.

When I contacted Yuneec tech support (UK) about this they reacted as if it was the first time they had heard of such a thing, and were unable to offer any speculation about why it happened without the telemetry. I was within warranty, and they offered to take a look for me, but instead I chose to monitor the situation, and haven't had a single repeat of it since the initial episode.

thanks for all of your input I will be keeping a close eye on this and I will inform you of what I get it figured out. This was the second time it occurred for me. The first time last not as drastic it's the last time.
as we speak I'm going to go into my st16 controller and look around at different things. I will be sending out the Telemetry files in the next few days. Hopefully somebody can read them because I don't know how.
Keith Kuhn

 

[KEITH KUHN]

I replaced my last TH because it would not decend properly. My solution was to activate home mode

Thanks for your input
I like home mode it has never failed me yet. I'm looking into my st16 controller for various things.
But I will test home mode once I take it back out for a test flight.
Keith Kuhn

 

[rdonson]

I hope you share the telemetry from the flight where you had the issue descending so that we may all learn what happened and hopefully why.

 

[KEITH KUHN]

Yes mine has done this on one occasion as well. I wouldn't say that makes it untrustworthy though - it is quite a rare occurrence, and eminently solvable - you just have to know how to deal with it when it happens. The key is not to panic, but I accept that is difficult not to do the first time this happens, especially if you were unaware it was a possibility... I certainly panicked initially, and that very much didn't help

There are several things you can do reported to work at one time or another...

1. Climb to about 100 ft and try coming down again. Repeat and see if it lets you descend past the invisible 'barrier'.
2. Cycle the landing gear.
3. Hold the throttle at minimum, and sometimes the craft will inch its way to the ground very slowly
4. RTH - this worked for me, but check you have GPS active and working before you call this Mode, and enough battery to handle a fast rise, and don't do it if there is any doubt about that.
5. Red button short presses (1 ft drop) are the most extreme solution, but tend to work every time.

When I contacted Yuneec tech support (UK) about this they reacted as if it was the first time they had heard of such a thing, and were unable to offer any speculation about why it happened without the telemetry. I was within warranty, and they offered to take a look for me, but instead I chose to monitor the situation, and haven't had a single repeat of it since the initial episode.

I am going to keep a close eye on the situation whatever develops I will keep you posted thanks for your reply Keith Kuhn

 

[KEITH KUHN]

I hope you share the telemetry from the flight where you had the issue descending so that we may all learn what happened and hopefully why.

I will get the files out ASAP thanks a lot Keith Kuhn

 

[CraigCam]

I suspect a dirty left stick. I have had this happen. The solution was to stir the stick and increase power by moving the slider towards rabbit. Check your hardware monitor and you will see that stick is not sending proper signal. You need to clean it and possibly calibrate the ST 16. There is no internal error other then the flight control not recognizing stick input because it’s not sending signal because it’s not properly outputting. One of my 480s has a problem ST that I’ve got to clean and check before flight or this stuff happens. Typically, it’s a lack of yaw response but can show up as loss of elevator control as well.

 

[PatR]

Should a fail to descend happen a quick landing solution for those just a little coordinated would be to elevate the H to a little over head height in Angle mode, hover, and grab one of the gear legs without trying to pull it down. Disarm motor as soon as you have a grasp of the gear leg.

 

[Dustoff]

Should a fail to descend happen a quick landing solution for those just a little coordinated would be to elevate the H to a little over head height in Angle mode, hover, and grab one of the gear legs without trying to pull it down. Disarm motor as soon as you have a grasp of the gear leg.

Unfortunately when it happened to me the bird was about 40 feet up in the air . No way to grab it .

I had already cleared out my files becuse I did a factory reset of the st16 due to another reason .

Makes sense about the dirty stick becuse it only did this on the first flight of the day , I have also noticed sometimes on the first flight of a day it’s slow to land but after a successful landing it goes back to normal

 

[CraigCam]

So I checked my hypothesis by pulling out my oldest and original 480 and ST 16. Sure enough, no elevator and lift off when in turtle. Moving the speed slider up got stick response but it was not normal and power was just low. Full rabbit behaved like turtle going up and down.

Upon landing, I checked hardware monitor. The stick showed signal all around but the behavior remained. A full shut off and quick squirt of air then DeoxIT got it back to normal behavior and proper power for take off in turtle.

 

[Dustoff]

I was thinking about getting a backup controller

 

[KEITH KUHN]

I suspect a dirty left stick. I have had this happen. The solution was to stir the stick and increase power by moving the slider towards rabbit. Check your hardware monitor and you will see that stick is not sending proper signal. You need to clean it and possibly calibrate the ST 16. There is no internal error other then the flight control not recognizing stick input because it’s not sending signal because it’s not properly outputting. One of my 480s has a problem ST that I’ve got to clean and check before flight or this stuff happens. Typically, it’s a lack of yaw response but can show up as loss of elevator l as well.

I am not sure what it could be it seems to me it might have something to do from when I go to Rabbit mode to Turtle mode, but
I will investigate it thoroughly and keep you posted. Keith. Kuhn