Strong Wind Warning -- scary situation

[Nospampls]

I flew my MA2 out over water about 3,900' to video a sailboat cooking along on spinnaker only. It does incredibly well in high wind (white caps on the water).

However, on the way back I got the following warning:

Strong wind warning. Aircraft unable to return to home automatically. Lower altitude immediately and return to home manually(Code: 30149)

It makes sense that it didn't want to ascend to the RTH altitude (65') because the wind might be even greater. However, it begs the question -- what would have happened if signal was lost and it couldn't "return to home automatically"?

It was flying fine. The video was smooth and the gimbal was never maxed out. It was about 25' above the water.

By coincidence the battery on my tablet died when I was almost home and the drone was visible. But I wouldn't have been able to manually retrieve the drone if that had happened earlier, assuming the message is accurate.

Has anyone had a similar experience? Or know anything more about this condition? If the message is accurate that's not a good thing. It should at least attempt to RTH.

 

[bumper]

I have no idea why I thought of this:

 

[Nospampls]

That's pretty sick

 

[InvisibleName]

That's pretty sick

The story or the song? ?

 

[lannes]

i guess you could set RTH to be lower over water, say 30ft if you know there are no obstacles in the RTH path.

Also fly into the wind, so that you'll have a tailwind to RTH in.

 

[Meta4]

However, it begs the question -- what would have happened if signal was lost and it couldn't "return to home automatically"?

It's a matter of simple arithmetic.
What speed does the Air 2 will fly at in RTH?
If it's the same as N mode (12 metres/sec - 26 mph) and you try to push directly against a 12 m/s wind, the drone stands still.
If the wind is faster, it goes backwards.
Even if the wind is half that strength, the drone would only make progress has 6 m/s.
If you were too far out, it might not get back before running out of battery.

The moral of the story is, don't get into a situation that means a tough fight against a headwind to come home.

 

[Nospampls]

From the serious responses, it's obvious to me that I wasn't clear. Pls bear with me as I try again.

The Strong Wind warning said " Aircraft unable to return to home automatically". I took that to mean that if the signal dropped or I requested RTH it would not automatically come home. I'm worried that it means what it said.

In my opinion that is a problem regardless of the wind direction or wind speed or drone altitude.

So my questions are:

1. Does anyone know if the warning is correct, i.e. RTH won't work under a Strong Wind warning condition?

2. If so, and the signal was lost, what would happen? Hover until the battery failed perhaps?

3. If the pilot requested RTH what would happen? Command ignored?

 

[Davros007]

Yes, interesting- would it have kept trying or just aborted the mission? Anyone?

 

[Ian in London]

From the serious responses, it's obvious to me that I wasn't clear. Pls bear with me as I try again.

The Strong Wind warning said " Aircraft unable to return to home automatically". I took that to mean that if the signal dropped or I requested RTH it would not automatically come home. I'm worried that it means what it said.

In my opinion that is a problem regardless of the wind direction or wind speed or drone altitude.

So my questions are:

1. Does anyone know if the warning is correct, i.e. RTH won't work under a Strong Wind warning condition?

2. If so, and the signal was lost, what would happen? Hover until the battery failed perhaps?

3. If the pilot requested RTH what would happen? Command ignored?

I'm surprised you got that message. The Air 2 can handle very strong wind, way beyond its specs, so I would imagine it would easily manage to return home if you initiated one or it lost signal.

 

[Meta4]

Yes, interesting- would it have kept trying or just aborted the mission? Anyone?

If your drone is being blown backwards while trying to RTH, that's what it will do until it gets to critical low battery voltage and then it will autoland way downwind.

 

[Meta4]

The Strong Wind warning said " Aircraft unable to return to home automatically". I took that to mean that if the signal dropped or I requested RTH it would not automatically come home. I'm worried that it means what it said.

It means that if you leave the drone to RTH one its own, you might go home with one less drone than you came with.

So my questions are:
1. Does anyone know if the warning is correct, i.e. RTH won't work under a Strong Wind warning condition?
2. If so, and the signal was lost, what would happen? Hover until the battery failed perhaps?
3. If the pilot requested RTH what would happen? Command ignored?

Your drone will always try to come home when you initiate RTH .. but if the wind is too strong for it to be able to get home, it's goodbye to the drone.

 

[Meta4]

I'm surprised you got that message. The Air 2 can handle very strong wind, way beyond its specs, so I would imagine it would easily manage to return home if you initiated one or it lost signal.

I don't have an Air 2 to check.
What speed does it RTH in in still air?
It's not going to be >12 m/s.

 

[Ian in London]

I don't have an Air 2 to check.
What speed does it RTH in in still air?
It's not going to be >12 m/s.

In Sports mode it can fly a spec'd speed of 19 m/s or 42 mph. However when I did this wind test above, the wind gusts were around 40 mph according to the flight logs, which is 19m/s, yet it handled this even when I flew in Normal mode, not Sports mode
So unllike the Mini, the new Air 2 does have additional capacity to handle winds beyond its specs, so it should easily handle a RTH flying into wind beyond 12 m/s.
But, as ever, the golden rule is fly out into the wind and fly back with the wind

 

[Meta4]

In Sports mode it can fly a spec'd speed of 19 m/s or 42 mph. However when I did this wind test above, the wind gusts were around 40 mph according to the flight logs, which is 19m/s, yet it handled this even when I flew in Normal mode, not Sports mode
So unllike the Mini, the new Air 2 does have additional capacity to handle winds beyond its specs, so it should easily handle a RTH flying into wind beyond 12 m/s.
But, as ever, the golden rule is fly out into the wind and fly back with the wind

But in RTH after losing signal, the drone will not use additional speed.
All DJI drones have a speed that they use for RTH and for the Air 2 it will not be >12 m/s.
If the wind speed is greater than the RTH speed, the drone is getting blown away.
You might be able to fly it at more than 12 m/s, but RTH won't.

 

[Ian in London]

But in RTH after losing signal, the drone will not use additional speed.
All DJI drones have a speed that they use for RTH and for the Air 2 it will not be >12 m/s.
If the wind speed is greater than the RTH speed, the drone is getting blown away.

I don't believe that's right; I'm not saying it will fly faster than 12m/s; I'm saying it has the thrust capacity to maintain 12 m/s even when flying into a strong wind.

 

[Nospampls]

OK. I tried my best.

 

[Meta4]

I don't believe that's right; I'm not saying it will fly faster than 12m/s; I'm saying it has the thrust capacity to maintain 12 m/s even when flying into a strong wind.

I've analysed the flight data from way too may blow-away incidents to agree with you.
Unless the Air 2 is different from all other DJI drones, it won't try to fly any faster than it's programmed RTH speed.
The drone can fly faster, but it won't use that additional speed in RTH.

 

[old man mavic]

@Nospampls for me ,the warning simply meant that in the event of a signal loss, there would not be enough battery charge left for it to make a safe return to the home point

 

[Ian in London]

But in RTH after losing signal, the drone will not use additional speed.
All DJI drones have a speed that they use for RTH and for the Air 2 it will not be >12 m/s.
If the wind speed is greater than the RTH speed, the drone is getting blown away.
You might be able to fly it at more than 12 m/s, but RTH won't.

Jump to 3:21 in the video. The

I've analysed the flight data from way too may blow-away incidents to agree with you.
Unless the Air 2 is different from all other DJI drones, it won't try to fly any faster than it's programmed RTH speed.
The drone can fly faster, but it won't use that additional speed in RTH.

Again, I'm not stating it will fly faster than 12 m/s; I'm saying it can still achieve or approach 12 m/s despite some headwind.
I've carried out strong wind tests on all my drones, specifically to test their capabilities when flying in winds that approach their spec'd max. The Mini is the only one that had no additional capacity to overcome the wind when flying into it.
Jump to 2:28 in this video on the 2 Pro. I'm flying directly into a very strong wind again around 40 mph. It's in Normal Mode, (spec'd max speed of 12 m/s) yet I'm able to reach a speed of 8.3 m/s which shows the ability to compensate for strong headwind and maintain a higher speed than you would expect if it limited its thrust to just 12 m/s.
Now, if you're saying that this will not happen in RTH mode but does happen in Normal flying mode, then without a specific RTH test flying against strong wind, I can't prove that (yet - I'll do a specific RTH test on the next windy day) but I would be surprised if they didn't carry over this ability to RTH mode when it's utilised on all other modes.

All my DJI drones except the Mini have proved time and time again that they will compensate to a large degree a strong headwind and maintain a speed that is greater than otherwise calculated by the spec'd speed minus the headwind speed.

Jump to 2:28

 

[Meta4]

Now, if you're saying that this will not happen in RTH mode but does happen in Normal flying mode, then without a specific RTH test flying against strong wind, I can't prove that (yet - I'll do a specific RTH test on the next windy day) but I would be surprised if they didn't carry over this ability to RTH mode when it's utilised on all other modes

Prepare to be surprised.
I'm surprised that you haven't encountered this issue before.
It's been a factor in the loss of many drones and the subject of many complaints to DJI.
Especially with the Mini that has an RTH speed of only 8 m/s.

Do a still air test first to establish what speed DJI have set for RTH Mode.
I'm not certain it is 12 m/s, just that it won't be more than 12 m/s.

All my DJI drones except the Mini have proved time and time again that they will compensate to a large degree a strong headwind and maintain a speed that is greater than otherwise calculated by the spec'd speed minus the headwind speed.

How accurate are the wind speeds you use for those calculations?