Please select Into the mobile phone version | Continue to access the computer ver.
First big crash - may help others NOT TO DO things !
796 23 2017-10-28
Uploading and Loding Picture ...(0/1)
o(^-^)o
Cyril Murat
lvl.2
Flight distance : 52431 ft
France
Offline

I all. I'd like to explain how I lost my first Phantom 3 Standard. My experience may help others not to do what I've done.
Situation :
Near a river with a 40 m high rock on the opposite side.
Safe place to takeoff and land on my river side.
Objective :
Fly above the rock to get nice pictures.
Preparation :
Preflight checks ok.
What happened :
When I arrived a little higher than the rock's top, I went to fly just above it. The quad ran out of my view behind the side of the rock and I lost the signal. It turned into landing mode, hit the top of the rock, felt on the rocks near the river and finished in the water. P3S was dead.
Why? What mistake?
I let the "Return to Home" mode in signal lost scenario in the app. The rock was within a distance of 20 meters and in that case, the plane does not fly back to the home point but descends immediatly.
What did I have to do :
Flying very close in a hostile environment, I would have better use the "HOVER if signal lost" function. The quad would have lose the signal and waited in place, giving me time to find a loccation where I can regain control...

Hope it will help other Phantoms to land safely...

2017-10-28
Use props
Labroides
Captain
Flight distance : 9991457 ft
Australia
Online

An even better idea would be never fly behind obstacles.
2017-10-28
Use props
hallmark007
Captain
Flight distance : 5486818 ft
  • >>>
Ireland
Online

Sorry to hear this, I suppose that RTH should figure highly in preflight check and depending on your environment and set it accordingly.
Hopefully you will get back up in the air soon, we’ve all made mistakes just some of us manage to get away with it.

Thanks for posting and above all your honesty.
2017-10-28
Use props
Cyril Murat
lvl.2
Flight distance : 52431 ft
France
Offline

Labroides Posted at 2017-10-28 01:51
An even better idea would be never fly behind obstacles.

Sure!!!
The best idea would have been NOT TO FLY in hostile environement before having hundred of hours of experience... I didn't want to fly behind but above. But the limit between above and behind the border of the rock is tiny...
My purpose was :
- even if you don't plan dangerous things (fly behind obstacles, fly very far away, fly between trees...), an incident can occure
- think twice for EACH flight what "no signal behavior mode" is best and don't always think "RTH" is the only way.
2017-10-28
Use props
Cyril Murat
lvl.2
Flight distance : 52431 ft
France
Offline

hallmark007 Posted at 2017-10-28 01:54
Sorry to hear this, I suppose that RTH should figure highly in preflight check and depending on your environment and set it accordingly.
Hopefully you will get back up in the air soon, we’ve all made mistakes just some of us manage to get away with it.

This accident is 2 mouth old and I do fly now with my brand new P3S... With more caution ;)
I'll take many many hours in easy environments before going back over water and near rocky objects
2017-10-28
Use props
KedDK
Captain
Flight distance : 1133038 ft
Denmark
Offline

Does anyone know what the idea about the 20m limit on RTH is, i can see a lot of scenarios where it is a bad idea to just land where it is with the only reason that AC is within 20m from take off, this scenario is a good example.

Did you save your AC/footage after the crash?
2017-10-28
Use props
Genghis9
Captain
United States
Offline

Well I'm glad you are back flying and thanks for the review and the lessons learned, much appreciated
2017-10-28
Use props
ALABAMA
Captain
Flight distance : 10356965 ft
United States
Offline

We ALL make mistakes, and always will. I just try to not make the same one twice.
2017-10-28
Use props
hallmark007
Captain
Flight distance : 5486818 ft
  • >>>
Ireland
Online

KedDK Posted at 2017-10-28 04:38
Does anyone know what the idea about the 20m limit on RTH is, i can see a lot of scenarios where it is a bad idea to just land where it is with the only reason that AC is within 20m from take off, this scenario is a good example.

Did you save your AC/footage after the crash?

It’s not available on all AC , I don’t think it’s available on P4Pro , what it is , you can set RTH to just land if it’s within 20 metres or climb to 2 1/2 metre and return to homepoint at that height you have to set this in your app,
2017-10-28
Use props
sSunSets
First Officer
Flight distance : 290856 ft
United States
Offline

Thanks for sharing your experience... I'll be looking at my RTH settings for more understanding. It sounded like the craft was barely out of sight behind the apex of the rock, and you being ground level. I might of tried more Altitude to get it back in sight the guided her into view. Maybe the RTH shouldn't have been used at all. I fly in open fields....  I lost my signal last evening while 350' up and 300 out. I just guided here back and down... no problems. Evening before last she 350' up and 350' out during late sunset. Visual on device was poor and I couldn't tell by lights what direction she was headed. Did the RTH, she kept. the Altitude to home point then landed. Was a small scare never the less. However, Seasons have changed now. Rain all next week, tempertures in the 40's Winter is just around the corner. I'm putting her away for next year.  
2017-10-28
Use props
Lucas775
Captain
Flight distance : 12109452 ft
  • >>>
United States
Offline

Thanks for the tips, I lost a P4 once flying under the bridge lost LOS and hit a pole of some sort and river swallowed my P4 and never seen it again.  I wasn't going to risk my life going in after it.
2017-10-28
Use props
Cyril Murat
lvl.2
Flight distance : 52431 ft
France
Offline

KedDK Posted at 2017-10-28 04:38
Does anyone know what the idea about the 20m limit on RTH is, i can see a lot of scenarios where it is a bad idea to just land where it is with the only reason that AC is within 20m from take off, this scenario is a good example.

Did you save your AC/footage after the crash?

.csv data and kml file attached.


I found back the bird under about 5 meters of dark water...

crash_p3s.zip

59.65 KB, Down times: 0

Crash data

2017-10-28
Use props
Kneepuck
Captain
Flight distance : 275102 ft
United States
Offline

sSunSets Posted at 2017-10-28 09:59
Thanks for sharing your experience... I'll be looking at my RTH settings for more understanding. It sounded like the craft was barely out of sight behind the apex of the rock, and you being ground level. I might of tried more Altitude to get it back in sight the guided her into view. Maybe the RTH shouldn't have been used at all. I fly in open fields....  I lost my signal last evening while 350' up and 300 out. I just guided here back and down... no problems. Evening before last she 350' up and 350' out during late sunset. Visual on device was poor and I couldn't tell by lights what direction she was headed. Did the RTH, she kept. the Altitude to home point then landed. Was a small scare never the less. However, Seasons have changed now. Rain all next week, tempertures in the 40's Winter is just around the corner. I'm putting her away for next year.

As I understand the op's post, he lost control signal, so he could not try to gain altitude.  The P3Standard uses a 5.8 ghz control signal and a 2.4 ghz fpv signal.  What you are describing is a loss of video signal, during which you can still control the aircraft.  By going behind a rock, the op lost control signal.  He did not mention whether or not he lost fpv as well, but I suspect he did.
Not much you can do in a situation like this, other than avoid these types of things.  A lesson harshly learned.  Glad he is back in the air with a new Phantom.
2017-10-28
Use props
sSunSets
First Officer
Flight distance : 290856 ft
United States
Offline

Interesting crash footage... Still nice footage of stone tower.... now we all know whats on top of that baby... That's a good a place as any leave a mark I guess.
2017-10-28
Use props
Genghis9
Captain
United States
Offline

Cyril Murat Posted at 2017-10-28 10:28
.csv data and kml file attached.
Link to the video.

Cyril
After looking at your crash video, I thought of another potential factor for future reference.  You personally may have also been too close; what I mean by that is when the bird went up it was nearly directly overhead, putting it in the signal weak zone of the antenna.  This either could have been a contributing factor to your loss of signal or the reason in itself.
You should have been more offset to ensure the craft remained in the strong signal zone of the antenna or placed the antenna parallel to the ground (pointing directly out) to mitigate this situation, especially if you could not offset yourself.
Here is a tutorial about this subject:
2017-10-28
Use props
KedDK
Captain
Flight distance : 1133038 ft
Denmark
Offline

hallmark007 Posted at 2017-10-28 08:49
It’s not available on all AC , I don’t think it’s available on P4Pro , what it is , you can set RTH to just land if it’s within 20 metres or climb to 2 1/2 metre and return to homepoint at that height you have to set this in your app,

IT was the behavior of just landing on the position it is when distance from HP is within 20m, not the height i was thinking about.
This crash would not have happen if on lost signal AC had keept height and moved above takeoff point before landing.
2017-10-28
Use props
KedDK
Captain
Flight distance : 1133038 ft
Denmark
Offline

Cyril Murat Posted at 2017-10-28 10:28
.csv data and kml file attached.
Link to the video.

Thank you, this video show much better than one can imagine from the description. :-)

I believe Genghis is right, it antennas had been set to point straight out you would have had better signal. But done is done, i am sorry for your loss.

Nice place, still thinking, whats on the other side of that rock ... ;-)
2017-10-28
Use props
repairman
lvl.4
Flight distance : 16581 ft
United States
Offline

hallmark007 Posted at 2017-10-28 08:49
It’s not available on all AC , I don’t think it’s available on P4Pro , what it is , you can set RTH to just land if it’s within 20 metres or climb to 2 1/2 metre and return to homepoint at that height you have to set this in your app,

the p3p will land prety much where its at with rth if the craft is 20m radius or less from home point.
2017-10-29
Use props
hallmark007
Captain
Flight distance : 5486818 ft
  • >>>
Ireland
Online

KedDK Posted at 2017-10-28 20:50
IT was the behavior of just landing on the position it is when distance from HP is within 20m, not the height i was thinking about.
This crash would not have happen if on lost signal AC had keept height and moved above takeoff point before landing.

That is the procedure for this AC you can set it to land on lost signal hover or fly to homepoint at altitude of 2.5 metre. So you can avoid what happened to OP but you must first have set correct RTH for your situation.
2017-10-29
Use props
KedDK
Captain
Flight distance : 1133038 ft
Denmark
Offline

hallmark007 Posted at 2017-10-29 02:27
That is the procedure for this AC you can set it to land on lost signal hover or fly to homepoint at altitude of 2.5 metre. So you can avoid what happened to OP but you must first have set correct RTH for your situation.

Thank you, didn't know, thought they all would just land when distance was below 20m.
2017-10-29
Use props
KM5RG-Robert
Captain
Flight distance : 2075213 ft
United States
Offline

Cyril Murat Posted at 2017-10-28 10:28
.csv data and kml file attached.
Link to the video.

Well that sucks. And an audience too.  
Very interesting rock formation though.   
I have personally railed against the RTH behavior within the 20m circle many times. It makes no sense to have that and your flight just reinforces that.
2017-10-29
Use props
M.C. Pilot
Captain
Flight distance : 9402165 ft
  • >>>
United States
Offline

"quad ran out of my view behind the side of the rock and I lost the signal. It turned into landing mode"

Thanks for sharing your experience. And, don't worry man it can happen. I don't care how many years or miles of experience a copter-pilot has, crashes can happen. I had my first first a couple of weeks ago even with a lot of experience.

From the video you'd posted it looks you went slightly beyond the side of the wall but was surprised the copter lost signal so quickly. Did you try to regain altitude? Did you loose video feed? When I've been in those situations of lost signal or weak signal, I immediately ascend and it regains signal strength. Learned lesson for next time. Good luck with your next copter.
2017-10-29
Use props
DNR 1
lvl.3
Flight distance : 1689478 ft
United States
Offline

Thanks for sharing this.

I thought you could set the RTH altitude to any height you wanted. If you go over the legal limit of 400 ft., I thought you get a warning saying you are going over the limit, but that doesn't stop you from setting it higher.
The issue here, I think, is that you did not have a safe RTH area, even if you set the altitude higher. So, in that case, yes, hover would be a better choice. The drone does not usually immediately land but ascends to either the default height or the height you set, or descends if it is already at that height, and will come down, I believe, within 65 feet of the home point. I guess the takeaway is if flying in an area that doesn't really have a safe RTH spot, then set to Hover. But more important is the cardinal rule to always keep the aircraft in line of sight. I almost always consider a RTH a bad thing and something I want to cancel asap if it happens. But you make a good point about Hover.
2017-10-29
Use props
DJI Diana
Administrator
Flight distance : 2408 ft

Online

Thanks for sharing this, lesson learned, good luck with your new drone, fly safe!
2017-10-30
Use props
Advanced
You need to log in before you can reply Login | Register now

Credit Rules