S800 sudden loss in altitude

[hazardpro]

Hi all

Took the S800 out last week, pretty rubbish weather and pretty windy, gusty (was a handful to fly).

Once thing I did notice was that on several occasions it would drop (pretty rapidly), on one occasion it must of dropped about 8 meters and I had to apply full throttle in order to keep control.

This only seemed apparent when flying in the windy conditions. I guess (hope) it was just due to the gusts of winds. But it wasn't exactly major wind, maybe 15mph with 25 gusts.

I thought I ready somewhere we people has reported a firmware issue causing altitude issues.

This all happened in GPS mode (didnt get a chance to test in other modes) on the day.

Im on firmware 5.18 (have been since purchase) and previous flights (all lovely weather) have been spot on.

Going to take it out tomorrow, hopefully the wind will be down and I can test.

Doug

 

[VINHEX]

There are some issues with 5.18, DJI have been asking users to upgrade to 5.20 BUT! 5.20 has issues with running heavy and has drops with vibrations.. Seems to be ok with 5.20 if lower that 6kg but they are warnings on site about 5.18 do not use... There is 5.16 on there to roll back as well..


Vin
Hexacrafter HC650, DJI WKM, DJI DataLink 2.4Ghz, 3s 3300, 3s 5000, Aeroxcraft Landing Gear, Xoar 12x6 props, Spektrum DX8, AR8000 Receiver
TM1000, Fatshark Attitude SD, Sony Exview Had II CCD 650 Line Sony Effio-E
Fatshark Spironet Antenna's, DJI iOSD

 

[Topflight]

Hazardpro,
I've been following an interesting tread over on RCgroups.com. Go to tread DJI Spreading Wings S800 Owners Tread. It's lenghty, so go up to page 400 and start. DJI is supposed to have a new IMU and vibration isolators to deal with problem

 

[Droider]

Is this JUST for S800 or all MR's over 6Kg using WKM?

 

[hazardpro]

So 5.18 is no good?
Should I revert to 5.16 or up to 5.20...

We are running a 7kg load...

Got a flight test on Thursday :s

 

[hjls3]

Hazard I am running fully loaded S800 and have had the vibration IMU altitude drop in both 5.16 and 5.20. I know that doesn't really answer your question but I seem to have less of it in 5.20. Also, turbulent air certainly amplifies the problem. Hoping to try one of the new IMU things but until then, I am ultra careful about how I descend and dont fly in much wind at all. WOuld be nice if the cutout for the IMU on the S800 were a bit bigger too. Doesnt take much to have the IMU touching one of the sides, introducing lots of vibes to the IMU.

 

[hazardpro]

Hi thanks for the reply... So the issues is down to IMU/ vibrations? This may explain why all my other flights (no wind) were not a issue.

Can you (or anyone) confirm about 5.18? I can't find any DJI notice/warning saying not to fly on it, but of course if 5.18 is no good ill have to update in the morning before I fly.

Thanks

Doug

 

[hjls3]

yep i for sure saw a warning from DJI not too fly 5.18 - and yep vibrations IMU - 5.20 has been okay for me. Just as many flights now on 5.20 as I had on 5.16. I certainly use extra caution though the wind.

 

[helloman1976]

Hi all

Took the S800 out last week, pretty rubbish weather and pretty windy, gusty (was a handful to fly).

Once thing I did notice was that on several occasions it would drop (pretty rapidly), on one occasion it must of dropped about 8 meters and I had to apply full throttle in order to keep control.

This only seemed apparent when flying in the windy conditions. I guess (hope) it was just due to the gusts of winds. But it wasn't exactly major wind, maybe 15mph with 25 gusts.

I thought I ready somewhere we people has reported a firmware issue causing altitude issues.

This all happened in GPS mode (didnt get a chance to test in other modes) on the day.

Im on firmware 5.18 (have been since purchase) and previous flights (all lovely weather) have been spot on.

Going to take it out tomorrow, hopefully the wind will be down and I can test.

Doug

This is a common issue with the Naza/Wookong flight controller, it could also be software related so never rule that out. Make sure you put black electrical tape on both sides of your Naza/Wookong flight controller. There's something with the barometric pressure sensor that gets all wacked out by changes in light and or direct Sunlight. I had the same exact issue, did the fix...I've had 62 flights since then with no issues. Hope that helps

PS - If you look at my Fort McCallister video on YouTube you'll see where I'm flying my 4lb DJI F550 in 45mph winds with absolutely no drop or rise in altitude unless I commanded it.

 

[hjls3]

If he is running NAZA on his S800 - he has other problems.

This is a common issue with the Naza flight controller, it could also be software related so never rule that out. Make sure you put black electrical tape on both sides of your Naza flight controller. There's something with the barometric pressure sensor that gets all wacked out by changes in light and or direct Sunlight. I had the same exact issue, did the fix...I've had 62 flights since then with no issues. Hope that helps

PS - If you look at my Fort McCallister video on YouTube you'll see where I'm flying my 4lb DJI F550 in 45mph winds with absolutely no drop or rise in altitude unless I commanded it.

 

[helloman1976]

If he is running NAZA on his S800 - he has other problems.

I should have said WooKong but whatever, same difference...same company...same old problem. Just don't cover any "holes" on the Woohong for pressure sensing. This is an age old bug...

 

[hjls3]

aye up Dave - I believe it has todo with the shaking beast that is the S800. Not 100% but it seems to be the one I read about and what I have experienced with mine. With load that thing vibrates like one of those beds you put quarters in. Not sure if you still have your S800 but I bet you remember that cutout for the IMU is barely big enough to fit the IMU, pretty easy to introduce vibrations to the mix. Lately I have seen DJI videos and Kopterworxs vids where the IMU is mounted on the landing gear and there is some additional vibration absorbing gizmos between LG and S800. Long story short - I thinks its S800 related. Not too worry about your beautiful bird.

Is this JUST for S800 or all MR's over 6Kg using WKM?

here si that DJi Video
http://www.youtube.com/watch?v=Sw5gJ1hzhHg
note the IMU location at 26 seconds.

What I gather from this is that DJI has figured out that a fully DJI product loaded bird it too much for the IMU in the S800 itself. So perhaps this altitude drop thing is not really related to any firmware - more related to the S800 not being really capable of handling the load and re-locating the IMU to a more vibration free place is a work around. BUT THESE ARE ALL GUESSES.

 

[djaguilar]

Make sure you put black electrical tape on both sides of your Naza/Wookong flight controller. There's something with the barometric pressure sensor that gets all wacked out by changes in light and or direct Sunlight.

Greetings, could you post a picture of where the tape goes? I had a really scary drop in altitude yesterday that had me puckering for a few hours. So I want to try this.

 

[helloman1976]

Greetings, could you post a picture of where the tape goes? I had a really scary drop in altitude yesterday that had me puckering for a few hours. So I want to try this.

No pictures but all you do is put black electrical tape on the side of the Naza so you cover the white parts. It worked for me and has ever since and it's been over a year and a hundred plus flights. Hope that helps.

 

[EastCoastJib]

No pictures but all you do is put black electrical tape on the side of the Naza so you cover the white parts. It worked for me and has ever since and it's been over a year and a hundred plus flights. Hope that helps.

So you did cover the hole or not? You put tape on all sides except where the hole is located?

Sent from my DROID RAZR using Tapatalk

 

[helloman1976]

So you did cover the hole or not? You put tape on all sides except where the hole is located?

Sent from my DROID RAZR using Tapatalk

You may be talking about the WooKong, the Naza doesn't have a hole that I'm aware of. I covered just the sides, the long sides of the rectangle. I don't own or have I ever owned a WooKong controller.