Hi guys

We've got some fairly blustery weather forecast this next week or so and it set me thinking as to what you'd do in a commercial position when it comes to weather. More particularly, wind speeds.

What would be the maximum forecast wind speed it's advisable to take a P4P out in?

Your manual tells you 22mph.

hallmark007 Posted at 2018-1-16 13:19
Your manual tells you 22mph.

I saw that so on my first flight I had confidence in the weather which was 10mph fixed with gusts of 22mph. Flying in a steady 22mph is also good though? Battery life should likely suffer though I'd guess, especially if a lot of the time is hovering for a shot or fighting the wind.

Hazy Jay Posted at 2018-1-16 13:56
I saw that so on my first flight I had confidence in the weather which was 10mph fixed with gusts of 22mph. Flying in a steady 22mph is also good though? Battery life should likely suffer though I'd guess, especially if a lot of the time is hovering for a shot or fighting the wind.

Yes wind will have effect on battery, phantom can fly in higher wind but always a risk. Always remember to to start flying up wind so as you have wind with you as you fly home.

It's not as simple as a magic number for fly/no fly.
The distance you want to fly and the direction of your flight relative to the wind have to be factored in.
And in stronger winds you also need to have a sheltered launch point.
The critical question is: What direction will the return flight be relative to the wind?

I had my p4p out the other week in 30 kph winds gusting up to 37 measured with a windmeter which I felt was my limit, although the drone and footage was fine. I didn't fly more than 400 m away and kept well away from obstacles.  I tested how well the drone flew upwind first from the launch point, as soon as I switched to sport it was buzzing around absolutely fine.

I think You have to be aware of if the AC switch to AttI mode. Then You have to manualy hold it up against the wind. Maybe Im wrong?

FarmerMac Posted at 2018-1-17 00:26
I think You have to be aware of if the AC switch to AttI mode. Then You have to manualy hold it up against the wind. Maybe Im wrong?

Well yes ..... but why would you want to switch to atti mode when dealing with wind?
It's not going to do anything extra to help you and will definitely make things harder (at best).
At worst, you go home with one less Phantom.

I've dealt with wind gusts up to 25 mph while taking panoramas with Litchi, and it was difficult to see movement from the P4P even when it was hovering, and this was just under 400 feet altitude.  That said, I've also taken pictures for insurance adjusters that required being close to houses, and this is not fun in gusty winds.  The houses apparently cause all kinds of updrafts, downdrafts and strange lateral movements that can really get your attention when you're in close quarters and fighting not to hit something.  In South Carolina, we call this "squirrelly".

Hazy Jay Posted at 2018-1-16 13:56
I saw that so on my first flight I had confidence in the weather which was 10mph fixed with gusts of 22mph. Flying in a steady 22mph is also good though? Battery life should likely suffer though I'd guess, especially if a lot of the time is hovering for a shot or fighting the wind.

It is the gusts that matter since they are what will blow it away, don't worry about the steady speed.

Also, if you are near the ground or buildings or trees then you can get turbulence which can make flying very difficult, for example if it gets an updraft that supports half its weight then it can only use half power to fly and that means it can only cope with winds half the speed it normally can.

In steady winds 45Km/h is about the maximum it will cope with in normal modes, beyond that you need to use sports mode to make progress against the wind.

You did mention "Commercial", in which case you should probably be able to control it in Atti mode, just in case you loose GPS.  Most pilots will have difficulty staying in good control in a 10 Km/h wind so it is the pilot that is the real limit!

If you are flying in strong winds then beware that RTH may not use enough power to get home if flying upwind without you telling it to use more power, so it is important not to get into a situation where you need to use RTH, or if you do then it needs to be upwind of you while doing it.  Also you shouldn't trust the obstacle avoidance in strong wind since although it will work, it will fly too close to things to keep clear of turbulence so can easily get into trouble.

Another thing to keep in mind is when flying in strong winds around structures, on the windward side of the structure you will get pretty hefty updrafts and on the leeward side of the structure, you will get equally hefty down drafts and those can make your Phantom do an unintended face plant.   Also between structures the wind velocity will get amplified considerably.   I would definitely sign up for some hull insurance.

Thanks guys

Labroides Posted at 2018-1-17 01:47
Well yes ..... but why would you want to switch to atti mode when dealing with wind?
It's not going to do anything extra to help you and will definitely make things harder (at best).
At worst, you go home with one less Phantom.

I wont..
But for some reason the GPS could fail.. And then You must be aware that you are on your own
holding the AC up against the wind.. ;)
If you haven't practiced ATTI mode that might end up in a crash.

Each flight you take be it commercial or hobby requires that you can undertake it safely. As Labroides points pi

Each flight you take be it commercial or hobby requires that you can undertake it safely. As Labroides points out it is not a simple matter as to fly or not. Many factors need to be taken into account. I would rather not do the jb and come back another day with my Phantom, rather than try and do it under adverse circumstances and not be able to come back another day because I have no Phantom. I always make sure that the customer knows that the work will only be undertaken if safe to do so.

FarmerMac Posted at 2018-1-17 05:24
I wont..
But for some reason the GPS could fail.. And then You must be aware that you are on your own
holding the AC up against the wind.. ;)

But for some reason the GPS could fail.. And then You must be aware that you are on your own
In four years of Phantom flying, I haven't ever had GPS fail.
GPS is very reliable and loss of GPS is most offten due to things the flyer did that caused a compass error.
In normal flying, losing GPS is about the last thing you need to worry about.

Labroides Posted at 2018-1-17 16:29
But for some reason the GPS could fail.. And then You must be aware that you are on your own
In four years of Phantom flying, I haven't ever had GPS fail.
GPS is very reliable and loss of GPS is most offten due to things the flyer did that caused a compass error.

Then you haven't been flying long enough . But seriously, the GPS even in a modern flight controller isn't infallible and it should be treated like the possibility of loss is greater than 0, enough so to have a backup plan in place. In fact, it's irresponsible to simply think it'll never fail and not have a Plan B for if it does go away for some reason.

I have to fly in strong winds all the time, almost always above 10mph and usually closer to 20, so I do at least some practice in atti mode in my P4P in high winds on a regular basis. You don't have to do it all the time, even just half a battery maybe once or twice a week in a stiff wind will really help. You'll be surprised at first at how much stick you have to hold in order to maintain a hover or navigate a course in atti, even in fairly low winds.

So basic proficiency in atti mode, especially in wind, is really a good idea and can mean the difference between going home with your whole bird vs just a transmitter in a pinch....

As for the OP, 20mph steady is about my limit with the P4P for recreational flying, but for trying to do videography, I lower the limit to 15. Above that the footage gets slightly shaky and it can be a pain to get smooth movement. Flying for fun, I've been caught out in 25mph winds before which requires sport mode just to keep from getting blown down wind. Which makes it not flying for fun anymore . So 20 is when I pack it in.

luciens Posted at 2018-1-17 18:38
Then you haven't been flying long enough . But seriously, the GPS even in a modern flight controller isn't infallible and it should be treated like the possibility of loss is greater than 0, enough so to have a backup plan in place. In fact, it's irresponsible to simply think it'll never fail and not have a Plan B for if it does go away for some reason.

I have to fly in strong winds all the time, almost always above 10mph and usually closer to 20, so I do at least some practice in atti mode in my P4P in high winds on a regular basis. You don't have to do it all the time, even just half a battery maybe once or twice a week in a stiff wind will really help. You'll be surprised at first at how much stick you have to hold in order to maintain a hover or navigate a course in atti, even in fairly low winds.

You are right..
I'm a brand new pilot, with only 1 hour of flight time
I wouldn't go fly in high wind above 10 m/s before i get more experienced
flying my drone, and without practic ATTI mode in moderate wind in a big
open space first.

embayweather Posted at 2018-1-17 05:35
Each flight you take be it commercial or hobby requires that you can undertake it safely. As Labroides points out it is not a simple matter as to fly or not. Many factors need to be taken into account. I would rather not do the jb and come back another day with my Phantom, rather than try and do it under adverse circumstances and not be able to come back another day because I have no Phantom. I always make sure that the customer knows that the work will only be undertaken if safe to do so.

I totally agree with this and it is how I would handle a job situation.

FarmerMac Posted at 2018-1-17 23:26
You are right..
I'm a brand new pilot, with only 1 hour of flight time
I wouldn't go fly in high wind above 10 m/s before i get more experienced

well fortunately, DJI flight controllers in GPS mode make flying in winds very easy. They stay put in hover by themselves and don't go too far off when you're flying a course even with fairly strong crosswinds. Of course, always fly only in conditions you're comfortable with, but you don't necessarily need to pack it in at the first sign of the branches at the tops of the trees moving either.

on the P4P you can "taste" atti mode by just switching to it and trying it out. If you get disoriented or otherwise uncomfortable, just switch immediately back to GPS mode and the copter will stop heading for the hills.....

Thanks for this post. I have a client that wants me to shoot tomorrow and UAV forecast (great tool) is showing wind gust in the neighborhood of 36mph. I told them that might be an issue. The site is surrounded by trees on one side that I thought might help but high and low lines on the other side (much more concerned about those).

FarmerMac Posted at 1-17 23:26
You are right..
I'm a brand new pilot, with only 1 hour of flight time
I wouldn't go fly in high wind above 10 m/s before i get more experienced

...and yet your status, equipment level and flight distance indicates you have considerably more than 1 hour in the air...
Probably a story there  somewhere hehe!

KennyB Posted at 12-19 12:41
Thanks for this post. I have a client that wants me to shoot tomorrow and UAV forecast (great tool) is showing wind gust in the neighborhood of 36mph. I told them that might be an issue. The site is surrounded by trees on one side that I thought might help but high and low lines on the other side (much more concerned about those).

I don't do commercial work.  As far as recreational, I do check wind before every flight, and I don't really concern myself too much with gusts.  I'm more concerned with the steady prevailing wind.  OTOH, 36 mph. even in gusts, is a lot of wind.  

You might take a close look at windy.com before you decide to cancel.  There's a bit of a learning curve associated with the site but it will give you a lot of good info if you're willing to spend a few minutes.

Labroides might have some good advice.

Good luck.

I don't fly my P4P in any winds higher than 20 mph.

KennyB Posted at 12-19 12:41
Thanks for this post. I have a client that wants me to shoot tomorrow and UAV forecast (great tool) is showing wind gust in the neighborhood of 36mph. I told them that might be an issue. The site is surrounded by trees on one side that I thought might help but high and low lines on the other side (much more concerned about those).

P4P can handle that in sports mode as long as you stay on site and dont fly more than a few hundred meters, away and dont go too high, remember, the higher you go, the stronger the winds get, that 36mph is for 10m height, you can probably add 5-20% over sea or 10-40% over land for a height of 100m, thats for gusts, you can add up to 80% for sustained speeds.

EDIT:

I draw the line at 30mph max gusts at 10m (forecast winds), and i would only go out then if its for the wind turbines, nothing more. I am only a hobbyist so for work i suppose i would have a different view......

For a job I'd limit it to 15mph (measured at take-off position) it will prob be a lot high at height - You need to ensure you'd get back easily and safely from a down wind position if you exited GPS. If its windy when you take off - just flick to ATTI mode and see what you would need to deal with in an emergency / issue situation. It might make you change your mind.

I had two flight scheduled today...the first one I mentioned where it was windy but the Phantom handled well. I think it was because the site was surrounded by trees on two side to help cut the wind a bit. The second site is a much flatter spot and I could tell that the wind was way worst. I took off briefly and then immediately called the flight off...the Phantom was doing OK but I could tell it was struggling.

The second site I am sure had sustained winds of about 20mph at the surface with gust up into the 30 mph.

Better safe than sorry.

As a general rule, most airline aircraft have a demonstrated crosswind limit of 30-35 kts, and please note that crosswind component can be different from windspeed. Winds from 310 degrees at 40 knots on a runway 31 would be a 40 kt. headwind component and a 0 crosswind component. If the winds were from 350 degrees at 40 kts and still using runway 31, you'd still have some headwind component, but it'd be less than 40 kts, and you'd have more crosswind component than before.

gameraqua Posted at 12-20 12:15
As a general rule, most airline aircraft have a demonstrated crosswind limit of 30-35 kts, and please note that crosswind component can be different from windspeed. Winds from 310 degrees at 40 knots on a runway 31 would be a 40 kt. headwind component and a 0 crosswind component. If the winds were from 350 degrees at 40 kts and still using runway 31, you'd still have some headwind component, but it'd be less than 40 kts, and you'd have more crosswind component than before.

Say what???  

I take my P4P out in some pretty insane winds. There was one time in the Polish mountains where I took my drone up in at the start of a storm front - the wind was absolutely blowing a gale and even in sports mode the drone was flying away and couldn't fight against the wind. I had to put it into atti mode, drop altitude and try and find wind sheltered regions to get it back but I thought it lost it a few times. There was another time where this happened in south Australia but luckily it was over land and I managed to somehow get the drone back after it was drifting away when flying into the wind. I'd estimate the wind speeds to be 60-70km/h both times. I'm more careful now since I'd prefer not to have to spend $2k on a replacement

Cradoka Posted at 12-19 14:23
...and yet your status, equipment level and flight distance indicates you have considerably more than 1 hour in the air...
Probably a story there  somewhere hehe!

Well.. My reply was from January 2018. Now almost a year later it correct that I’m a bit more experienced

It should be 10 m/s but I flown in 40 km/h wind without a problem. The thing is that, speed of the aircraft is relative to wind speed.

gameraqua Posted at 12-20 12:15
As a general rule, most airline aircraft have a demonstrated crosswind limit of 30-35 kts, and please note that crosswind component can be different from windspeed. Winds from 310 degrees at 40 knots on a runway 31 would be a 40 kt. headwind component and a 0 crosswind component. If the winds were from 350 degrees at 40 kts and still using runway 31, you'd still have some headwind component, but it'd be less than 40 kts, and you'd have more crosswind component than before.

Okay - reading this post again ten days later - I've now learned how runways are numbered.  Never knew that.  THANKS

Mark The Droner Posted at 12-30 13:22
Okay - reading this post again ten days later - I've now learned how runways are numbered.  Never knew that.  THANKS

Runway numbering is elementary. It is the magnetic heading!