Splashdown of Anafi in Water. Beware.

PeterL · Feb 12, 2020

I'm wondering if anyone else has lost their Anafi drone in the water and, if they know why. I recently lost mine under mysterious circumstances. I was flying at a local marina and came down slowly while moving forward slowly for some video at deck height of the docked boats. The drone got too low for comfort (I estimate 8 ft) and so I released both joysticks. However, the drone did not stop and hover, as it usually does, it kept on the previous trajectory (forward and down) and splashed into the water (they sink!).
The Anafi user's guide v2.6.2 mentions water in 2 places. On p24 where it warns "do not fly over water" without any specifics and on p48 in the section on panorama shots where it says "do not take a panorama less than 30 ft (10m) above water".
I called Parrot to ask if I could buy just a replacement drone to pair with my controller. The answer was no. But when I told them my story they allowed me to file a warranty claim. 1 month later, after several exchanges of paperwork and the return of my Skycontroller 3, they sent me a whole new kit. Very nice of them, but I still want to know what happened so I can avoid it in the future. After all, 71% of earth's surface is water!
I have a hypothesis and wonder if there are any engineers out there who might shed some light on the situation. I read that the Anafi uses dual-band Wifi at 2.4 and 5.8GHz. I also know that water absorbs 2.4GHz like crazy. The frequency of your home microwave is 2.45GHz. I imagine that when the Anafi is flying low over the ground, the transmitted WiFI from the controller reflects off the ground to hit the Anafi's antennas which are embedded in the 4 arms. Perhaps when the Anafi is low over water there isn't enough reflection of WiFi off the water to maintain the control link and the Anafi continues on it's previous trajectory during this "blackout". Perhaps a way to test my hypothesis is to turn off the controller (fold it closed) while flying low over the ground and see if I can repeat what happened (less the splashdown). I'd appreciate hearing from those who also lost an Anafi in the water. Or from Parrot themselves! I asked customer support TWICE if they could describe the failure mode. But received no response.

ROBANAFI · Feb 13, 2020

Was the water really still since you were flying over a Marina? I'd hazard a guess and say your vertical camera couldn't see the water wasn't a solid object. I've flown low across a lake but the water was rippling so it kept its altitude

PeterL · Feb 13, 2020

Yes, water was smooth, but the vertical camera prevents descent when you reach about 2'. I was at 8' when I released the joy sticks and the drone continued down. That's the mysterious part. Beautiful footage of the lake. How high were you and how far away was the drone? You have proved that you can fly low over water!

Joe_Scot · Feb 13, 2020

Although the manual does say not to fly over water, I have risked it a couple of times (and been lucky!!)

The opening sequence of my film in this post:

Autumn in Scotland

I've been working on a little project the past couple of months - helped by some amazing Autumn weather here, especially at weekends. Have finally edited it and published on YouTube... Autumn in Scotland

parrotpilots.com

... was at an altitude of 3m over still water - I flew for 200m and then increased altitude.

My other example was actually slightly lower - logs show 2.5m altitude (takeoff was right next to the water's edge) - again very still water.

Sorry it doesn't explain what happened to yours, but it does maybe point to a malfunction. Great that Parrot replaced yours OK!

pmh1nic · Feb 14, 2020

I've flown high and low over water...

Beach

without any issues but it wasn't really calm water.

mbetts · Dec 23, 2020

PeterL said:
I'm wondering if anyone else has lost their Anafi drone in the water and, if they know why. I recently lost mine under mysterious circumstances. I was flying at a local marina and came down slowly while moving forward slowly for some video at deck height of the docked boats. The drone got too low for comfort (I estimate 8 ft) and so I released both joysticks. However, the drone did not stop and hover, as it usually does, it kept on the previous trajectory (forward and down) and splashed into the water (they sink!).
The Anafi user's guide v2.6.2 mentions water in 2 places. On p24 where it warns "do not fly over water" without any specifics and on p48 in the section on panorama shots where it says "do not take a panorama less than 30 ft (10m) above water".
I called Parrot to ask if I could buy just a replacement drone to pair with my controller. The answer was no. But when I told them my story they allowed me to file a warranty claim. 1 month later, after several exchanges of paperwork and the return of my Skycontroller 3, they sent me a whole new kit. Very nice of them, but I still want to know what happened so I can avoid it in the future. After all, 71% of earth's surface is water!
I have a hypothesis and wonder if there are any engineers out there who might shed some light on the situation. I read that the Anafi uses dual-band Wifi at 2.4 and 5.8GHz. I also know that water absorbs 2.4GHz like crazy. The frequency of your home microwave is 2.45GHz. I imagine that when the Anafi is flying low over the ground, the transmitted WiFI from the controller reflects off the ground to hit the Anafi's antennas which are embedded in the 4 arms. Perhaps when the Anafi is low over water there isn't enough reflection of WiFi off the water to maintain the control link and the Anafi continues on it's previous trajectory during this "blackout". Perhaps a way to test my hypothesis is to turn off the controller (fold it closed) while flying low over the ground and see if I can repeat what happened (less the splashdown). I'd appreciate hearing from those who also lost an Anafi in the water. Or from Parrot themselves! I asked customer support TWICE if they could describe the failure mode. But received no response.

Peter,
Appreciate you sharing your experience, as an Anafi pilot myself in Florida, I routinely fly over water, though its a much higher heights than what you were flying over. I wonder if at higher altitudes, the 2.4ghx signal being transmitted is able to bounce off the water, as it sees it as a more stable surface, vs the eight or so feet in which you were flying? a recent Anafi owner and you tuber "TDR Drones", recently experienced the same issues, and lost his Anafi in the river for which he was flying. He attributed it to magnetic interference in the area in which he was flying, as he received warning messages on his screen to that effect. So, it seems the jury is still out as to whether its safe to fly over water, and if so, what is a safe height??

Gipsz Jakab · Dec 23, 2020

mbetts said:
Peter,
Appreciate you sharing your experience, as an Anafi pilot myself in Florida, I routinely fly over water, though its a much higher heights than what you were flying over. I wonder if at higher altitudes, the 2.4ghx signal being transmitted is able to bounce off the water, as it sees it as a more stable surface, vs the eight or so feet in which you were flying? a recent Anafi owner and you tuber "TDR Drones", recently experienced the same issues, and lost his Anafi in the river for which he was flying. He attributed it to magnetic interference in the area in which he was flying, as he received warning messages on his screen to that effect. So, it seems the jury is still out as to whether its safe to fly over water, and if so, what is a safe height??

If you think about this video, it has nothing to do with flying over water. It was the result of a battery handling error and an uninterrupted automatic landing. This would have happened over land as well (the drone would only have been found)