Make sure to take wind into consideration!

Bcornell11 · Mar 6, 2017

I was flying over the ocean the other day filming humpback whales and got carried away while filming. The RTH started while I was a little over a mile out South and East of take off. I turned off RTH after I soon realized the wind picked up and was not going to make it back (sport mode maxed at 15mph). This is when chaos and panic started as I was over the water and had to make a quick decision to head perpendicular to the coast not diagonal to home. Long story short the battery gave out 10ft from landing in the ocean and crashed into a tree. Made sure it was a secluded spot otherwise I would of bit the bullet.. There was enough battery to locate the drone on the screen thankfully and even more thankful the drone was fine just replaced a questionable prop. It will be the last time I'll wait for the RTH to initiate.

larkin · Mar 6, 2017

Good tip. This is another place I wish the Mav integrated calculation of a wind vector. The other place is to either always display the wind vector (averaged over some time window) or give wind speed when issuing wind warnings.

voongnz · Mar 6, 2017

Bcornell11 said:
I was flying over the ocean the other day filming humpback whales and got carried away while filming. The RTH started while I was a little over a mile out South and East of take off. I turned off RTH after I soon realized the wind picked up and was not going to make it back (sport mode maxed at 15mph). This is when chaos and panic started as I was over the water and had to make a quick decision to head perpendicular to the coast not diagonal to home. Long story short the battery gave out 10ft from landing in the ocean and crashed into a tree. Made sure it was a secluded spot otherwise I would of bit the bullet.. There was enough battery to locate the drone on the screen thankfully and even more thankful the drone was fine just replaced a questionable prop. It will be the last time I'll wait for the RTH to initiate.

Many drones have gone down in rth while flying into a headwind. This wont be the last. Glad you found a way to save it from a swin.

Strafe1 · Mar 6, 2017

Good lesson for everyone!

stratos · Mar 6, 2017

My advice is always check wind direction before takeoff.
I always try to fly if possible, against the wind and try to position myself on the return with the wind, so the wind pushes me back home.

It does take some practice but its definitely worth it having the reassurance that the wind will help you come back home.

Another advice is that always return before you actually hit the RTH distance. I prefer to land with 30% non spent battery, that biting my nails on my way back with only 20% battery

rydfree · Mar 6, 2017

Wind can be drastically different just a little high up also . I wish my friend had sent me a little longer clip of the Mavic than this but we were filming each other and while the wind was near zero mph at ground level it was bouncing the little Mavic around at 167' . You couldn't tell by looking at the video feed though as it was solid as a rock . I was getting high wind warning though . The begining of this video is the Mavics view of his Inspire 2 and the last few seconds shows the Mavic from his camera .

The higher you go the stronger winds you can incur .

TTFullTimer · May 18, 2017

You made the right decision to use the shortest path to dry. I always told people on my boat before we ventured offshore that if it was necessary the boat would be run to the closest dry spot available regardless of where we had entered the ocean. Run it up on shore and jump off. Fortunately you had that huge reserve of ten feet from shore. And the same as with boats water currents and wind are always variables. The Mavic was probably doing its near 40 mph through the air, but the air was moving off shore at some number near 25 mph.

Kingkong · May 18, 2017

Just a thought how do we take wind into consideration,

if we go out full sport mode speed knowing what the full sport mode speed is with no wind then

if the speed is higher then we must have a tail wind
If the speed is slower and we must have a head wind

therefore you will know that you have a tail or head wind and take it into consideration

I can.t recall what the max speed is in sport mode maybe 60kph?

TTFullTimer · May 18, 2017

Kingkong said:
Just a thought how do we take wind into consideration,

if we go out full sport mode speed knowing what the full sport mode speed is with no wind then

if the speed is higher then we must have a tail wind
If the speed is slower and we must have a head wind

therefore you will know that you have a tail or head wind and take it into consideration

I can.t recall what the max speed is in sport mode maybe 60kph?

Good idea to watch speed. Sport mode is about 60 kph or 40 mph. So you can just subtract that from the speed you see on the controller. Negative means headwind Positive means tailwind. When you are out as far as you want, you can estimate how long it will take to get back. If you went out against a head wind it will take less time to come back. If with a tail wind it will take longer to get back. I would write a formula for that but who would remember it when the Mavic is complaining about low battery. With my luck the wind would shift and I would be bucking a headwind both ways. I have set a limit of 500 meters or 1500 feet or so. That is about as far as I can see the Mavic in the sky and I can still hear it faintly. I have not yet flown in Sport mode. The dadgum thing already goes too fast in GPS mode. I have not run long enough yet to get a battery warning while at that distance. Where I have been flying if the Mavic went down it would be a long hike in bad territory to retrieve it if I even found it.

fokker · May 19, 2017

Quick trick I do is take note of speed when flying full throttle. Since I know my top speed when calm is 20 mph, if the speed is greater I know I'm flying with the wind and if less I'm flying into the wind.

For example if my speed is 25 flying out, it's usually 15 flying back in sustained winds. Not terribly scientific but it's a quick way for me to guestimate wind direction and speed for RTH especially if I know I'll be returning with a headwind.

Another thing to remember is wind speed is usually higher with altitude, so don't rely on auto RTH with a headwind. Fly back manually as low as you can go to get the fastest most efficient return speeds.