Fog / Low level cloud making ATT/Height level error

[Rcc]

I was start flying from a hill at the coast, it was a bit foggy and it was 50M and suddenly 0.3M in red, when lost RC singal, RTH active, it couldn't land, it showing 0.3M height Slide to land, but aculty the spark on at least 50M from my head, I was wondering if I slide to land do you think the Spark would fall from the sky, then I realised may be the fog effect the height sensor, then keep move it forward the backward, still can't land, at the end I press X to cancel RTH, I land it with RC, when it lower then 30 M it was no fog. ... the ATT read normal again.

 

[Dronason]

After a RTH, it will not land on its own until battery is very low. It will hover at 0.3 m distance given normally by its vertical distance sensor, it will wait for user confirmation for landing. The vertical is an infra-red laser sensor, so fog, clouds, low light ... can definitively affect it.

 

[Clark W. Griswold]

I too, can attest to this. Lost little sparky over a lake yesterday after it got into some fog/mist....lost wifi signal, GPS signal lost, and RTH wouldn't work.
RIP Sparky, RIP :-(
.....lol

 

[Bubbles!!!]

I was flying in some fog on my trip across the country 2 weeks ago and had the same things happen, I was close so I didn't lose signal, but my height kept jumping between the actual one, and into the red numbers.

Guess we've found an environment that the spark can't fly in! Maybe if there's a fix a future update could help, doubtful though since it's affecting sensors instead of software...

 

[Kilrah]

Other DJI aircraft let you disable the affected sensors so no such issue. For some reason they decided the Spark needed to be "simple" and removed lots of useful but "potentially confusing" options.

 

[His415]

Interesting about the fog, the manual says don't fly it in the fog, but I always figured it was because of moisture getting sucked into the fans.

 

[Buddy411]

Very surprising the Spark is only relying using sonar to determine altitude and not a barometer. I know GPS isn't ideal for altitude, but having a third data input wouldn't hurt to help the Spark figure out how high it is.

 

[Pac]

Very surprising the Spark is only relying using sonar to determine altitude and not a barometer. I know GPS isn't ideal for altitude, but having a third data input wouldn't hurt to help the Spark figure out how high it is.

Does it have sonar? I thought its sensors are infrared and optical only. And really, no barometer?

 

[Kilrah]

Of course barometer is the main source of alt info like on every other DJI aircraft. The sonar / vision / IR is just an added source of data when close to the ground which is great for precision in good conditions, but can also be fooled in some cases and cause trouble.

 

[Pac]

I agree Kilrah that the spark has a barometer, that's why I questioned Buddy411. However, I dont know where the sonar is located and doubt there is one. The mavic has two ultrasonic sensors (and no IR).

 

[Kilrah]

Different aircraft have different sensors, the Spark has visual and IR, no sonar.
IR serves the same purpose as sonar on others though, just with shorter range.

 

[Dronason]

Different aircraft have different sensors, the Spark has visual and IR, no sonar.
IR serves the same purpose as sonar on others though, just with shorter range.

Absolutely correct. The main element for the altitude is a barometer in the Spark. The Spark uses its infrared vertical sensor to detect proximity to the ground. If it report wrongly (fog, low light, special surface) a short distance it could think it is landing or too close to the ground. The barometer is not always perfect and can have drift between take off and landing by a substantial amount. The vertical proximity sensor will help the Spark to stop at proximity of ground in a RTH and it is the pilot that finish it. The vertical proximity sensor is also not always working fine and you could have sudden drop in its reading. The Spark usually handle correctly, but it is always better to be able to detect any issue with vertical positioning and take control manually to avoid wrong forced landing.

 

[Pac]

Thanks all for confirming me that Spark indeed has a barometer and no sonar but IR.