So that's what that wind warning is about!

[WBN3]

That's interesting. Try measuring the wind when you get a warning, using ATTI drift hover. I'm sure you'll see what I've seen, most the time it's under 5mph when you get the warning on a calm day. There have been times with it's truly windy, and it warns immediately of course, but when it warns when calm on the ground, measure it at altitude with ATTI.

In the firmware settings the two wind warnings are clearly set to 6 and 9, not 7. The question is the unit of measurement. I never deal with this issue anymore because I've bumped mine up to 30 and 40km/h.

I'm not sure I understand all of this, but I assume you're using the GPS-based speed over ground with no stick inputs to derive a wind speed. If so, that assumes that the P4 is acting as a perfectly efficient sail and moving at the same speed as the wind. I believe that may be the difference in your and Meta4's experience. As for the hand-held anemometers that @AuldGimpy reported using, the question is whether they were at the same altitude as the bird. From the description (flying off a bridge), it may have been. The OP reported flying at 300 ft. where wind can be much stronger.

Appreciate all the contributions... this is an interesting discussion.

 

[Ahmadp044]

I get wind warnings even if there isn’t much wind but I guess it’s for safety reasons

 

[John Locke]

Here are a couple of DJI people commenting on the speed warning settings. I see one is saying 6 m/sec

High wind warnings
High Wind Warnings
Flyaway - Healthydrones​

Gimbal flips? They were common in very early firmware but I haven't seen any gimbal flipping for a long time and I mostly fly with OA disabled.
I thought that was fixed long ago with a firmware update.

Thanks Meta, that's an interesting read. All the DJI folks seem to think in terms of m/sec for wind speed, so I see your point. It's just that the evidence doesn't match when actually measuring with ATTI drifts on a calm day when the warning appear. All the other parameter numbers seem to be km/h, but the manual always refers to m/s for wind, so it makes sense to me that's what they are, like you said. Hmm. I saw one statement in those threads that said there was a note in the user manual about wind warning numbers. I haven't been able to find that in the P4P manual, maybe that's in other manual, such as P4 or Inspire.

 

[John Locke]

I'm not sure I understand all of this, but I assume you're using the GPS-based speed over ground with no stick inputs to derive a wind speed. If so, that assumes that the P4 is acting as a perfectly efficient sail and moving at the same speed as the wind.

You're point is noted, but wind can vary, so yes, drift measurements obviously cannot be accurate to within .1mph. However it's more accurate than DJI's method IMO. You can accurately estimate your wind-speed at altitude when you're drifting ATTI, it's pretty close. When drifting, the craft speed increases, it grows and grows. As you see the craft speed increase it will eventually stop growing in speed, and when the number decreases by .1mph, you know you're very close to actual wind speed. Aside from gusts, this measurement is about as close as you'll get with any method, and for me it's very representative of average wind-speed of the craft.

Keep in mind DJI is measuring wind-speed based on the attack angle of the craft, using the IMU as an "educated calculated guess", based on measuring how level the craft is. I think DJI's method is a much rougher estimation of wind than actually drifting with the wind in ATTI. This may be the reason I'm seeing measured speeds of less than 5mph, when they should be at least 13mph (6m/s), if we believe the unit of measurement in the parameter is m/s. In the parameter firmware, wind warning is set for 6, and the secondary warning is 9. If the unit of measurement is m/s, that's 13.4mph and 20.1mph. The resolution accuracy of the IMU could be inaccurate enough to trigger warnings way before these speed settings. The more I think about it, the more I think that's what's actually going on here. That's why so many warnings are irrelevant.

 

[Meta4]

I'm seeing measured speeds of less than 5mph, when they should be at least 13mph (6m/s)

It could be that a Phantom in atti mode doesn't drift at 7 m/s in a 7 m/s wind?
I haven't seen any testing to find out but the Phantom would have some drag that would make it drift at less than the velocity of the wind around it.
Something interesting to play with some day in a known wind strength?

The more I think about it, the more I think that's what's actually going on here. That's why so many warnings are irrelevant.

One thing's certain, for most flying the warnings are just an annoyance rather than being useful.

 

[Meta4]

It could be that a Phantom in atti mode doesn't drift at 7 m/s in a 7 m/s wind?
I haven't seen any testing to find out but the Phantom would have some drag that would make it drift at less than the velocity of the wind around it.
Something interesting to play with some day in a known wind strength?

I experimented today. I was offshore photographing a ship that was reporting a steady 17kt (8.75 m/s) wind.
When the shoot was finished, I switched to atti mode and the Phantom got up to 8.1 m/s being blown along.
It would appear that at 17kts windspeed, drag is not much and the atti drift speed is close to the wind speed.

 

[John Locke]

I experimented today. I was offshore photographing a ship that was reporting a steady 17kt (8.75 m/s) wind.
When the shoot was finished, I switched to atti mode and the Phantom got up to 8.1 m/s being blown along.
It would appear that at 17kts windspeed, drag is not much and the atti drift speed is close to the wind speed.

Hey, you beat me to the punch. I was going to mess with this tomorrow with an anemometer I bought last year. But I'm going to need some wind and lately here in California it's been dead calm.

In theory, the more wind drag the drone has the more accurate the reading would be to match windspeed, it would seem to me. The drag, like the landing gear hanging down, would catch wind like a sail, to match the wind speed better.

@Meta4, you seem to do a lot of ship photography. Is this a hobby, or have you developed contacts that want their ships photographed from the air? You've taken some great photos at sea. Big ships fascinate me, like big locomotives. Massive tools.

 

[Meta4]

@Meta4, you seem to do a lot of ship photography. Is this a hobby, or have you developed contacts that want their ships photographed from the air? You've taken some great photos at sea. Big ships fascinate me, like big locomotives. Massive tools.

Thanks .. I started doing it for myself because ships under way are such great photo subjects and the drone made it possible to shoot out there.
I get approached by some ship owners and agents and when I get something special, I try to track the owners down.
Here's a piece I wrote for DJI about it: Life at Sea from the Air– Photographing Ships with the Phantom 4 Pro
And here's today's ship, a Japanese deepsea research vessel:

 

[John Locke]

Here's a piece I wrote for DJI about it: Life at Sea from the Air– Photographing Ships with the Phantom 4 Pro

Good article, great photos, good tip on the AEB to mitigate the wrong F stop. Now I want to visit Long Beach tomorrow. Hah!

 

[Bakersfield Quad]

I experimented today. I was offshore photographing a ship that was reporting a steady 17kt (8.75 m/s) wind.
When the shoot was finished, I switched to atti mode and the Phantom got up to 8.1 m/s being blown along.
It would appear that at 17kts windspeed, drag is not much and the atti drift speed is close to the wind speed.

I think that there are always possibilities of errant wind gusts, shears or chop. I am sure the flight computer would flag a warning based on these too. I was flying recently, pretty calm and I was on a 60 foot mound, so exposed somewhat. Suddenly I got a warning, I was down wind of the P4P. The bird was maybe 300 feet away, in a very dhort time, seconds, a strong gust hit me, the calm. The P4P saw it first, I saw it second, brought it down sand in a minute or so, 12 to 15 mph gusts, so maybe 20 to 30 mph.
So, the bird might experience something that you don't, doesn't mean the warning was in error.

 

[AirMan05446]

Gimbal flips? They were common in very early firmware but I haven't seen any gimbal flipping for a long time and I mostly fly with OA disabled.
I thought that was fixed long ago with a firmware update.

I'm on current FW, and still get gimbal flips. I also suspect flying too fast in high wind eventually burned out a motor on my gimbal. No such issues with my Mavic -- it's an exceptional wind flyer.