What if you lose GPS flying and no line of sight to return home?

[BJR981S]

I see a lot of suggestions here most of them will not help very much.

It depends on what has been lost.

• The Entire GPS. Total Failure or wire fell out.
• Or just a loss of GPS lock due to atmospheric conditions.

The First is most likely going to be say goodbye to your drone.

The second is OK. The Magnetic compass does not need the sat lock to determine the correct heading. Just know what compass direction you are flying in and then if the worst happens yaw her around 180 Degrees. Also if you still have your camera. Fly as high as you can and find land if you are over the ocean.

I suspect it will still show you the heading to your home point anyway..

Cheers

 

[Bachi]

Hey all

Hypocritical question here..

If you are flying your mavic about 1 mile away and all of sudden you lose GPS mode and it switches to ATTI - how could you return the bird home?

Lots of times I'm flying out over ocean or inland so even a video signal on the phone may not be enough be able to clue together how to get the bird home...what would you do then? in ATTI mode only?

Thanks

I would try the "Home Lock" intelligent mode hoping that it follows compass directions and not GPS. Test it in a safe environment first...

 

[DJI27]

No - we talked about following scenario:
a) GPS lost, so aircraft is in ATTI mode
AND
b) C&C link lost

In that very moment (ATTI mode ) the FC has no clue where the aircraft is and where it should go to.
The only sensors the FC can rely on are the barometric sensor and its gyros (IMU).
These sensors are now used to keep the aircraft level and at altitude.

If the C&C link is active, the aircraft can still be controlled with the sticks, but the AC can/will drift with the wind.

Nice explanation .... for RTH to work... the bird FC needs to know end points (i.e. where it is and where it has to go)... loss of GPS means it doesn't know where it is (i.e. it loses an end point), so RTH can not help get the bird back home.
,
Assuming you still have C&C "AND" a video connection your only recourse is to figure out where the bird is by using land marks and then guide it back home manually by watching how landmarks change... exactly like a real pilot would have to do in the days before GPS

 

[Scottd9000]

I was flying over a large lake at sunrise and my iPad died due to cold. It was hovering way out and right in the sun. Basically had to just trial and error using sound to tell if it was getting closer. Coming from an original Phantom home lock was nice to have on the controller.

 

[Keule]

Basically had to just trial and error using sound to tell if it was getting closer.

Just look at the distance meter on your RC. Then:

a) Push elevator stick forward - is distance increasing or decreasing?
b) Yaw a little bit in one direction.
c) Look again on the RC's distance meter.
Is distance decreasing? If yes, keep current heading. If no, goto b)
Fine adjust if neccessary.

 

[Grizzo]

There is one other thing you can try which is better than doing nothing at all and letting it crash.
You can close or cover you antennas to weaken the RC signal and then fly in various directions until you get a stronger signal. Then keep flying in that direction and keep a look out for it returning in the last known direction. If you were flying low then it would be a good idea to go higher as well. More chance of spotting it.

 

[wytnyt]

Well if it's ok for the Chief - it's ok for me

Trump Administration Expands Drone Use to Beyond Visual Line of Sight

really?

 

[Skymax]

However, the compass should still work, right? So yaw the aircraft around until the arrow is pointing back at you, and then full-throttle forward until it comes back into view. Watch the video feed and avoid any obstacles.

Correck, Sport Mode is you're friend when you lose GPS, but remember the arrow wont point at you if you are one of those experts that says, "I never bother to calibrate the compass", and you are flying from a new site.

 

[kakao]

Correck, Sport Mode is you're friend when you lose GPS, but remember the arrow wont point at you if you are one of those experts that says, "I never bother to calibrate the compass", and you are flying from a new site.

Are you 100% sure about that?

/

 

[daisy-girl]

The aircraft will land at its current location.

Off topic: What is the procedure that you use for adding your signature to your posts (i.e., your equipment)?

 

[Qoncussion]

That confused me too, it's one of the intelligent flight modes, but if your phone disconnects and isn't working, will it still let you switch flight modes?

This may have already been answered, but I was flying in Active Track when Go4 crashed on my Android phone. So I flipped to sports mode... Nothing! Still in Active Track. I hit pause... Nothing. I had to get the app back up to stop the drone from following me everywhere I walked

 

[Regulator247]

Hey all

Hypocritical question here..

If you are flying your mavic about 1 mile away and all of sudden you lose GPS mode and it switches to ATTI - how could you return the bird home?

Lots of times I'm flying out over ocean or inland so even a video signal on the phone may not be enough be able to clue together how to get the bird home...what would you do then? in ATTI mode only?

Thanks

Why wouldn't you just flip to the map mode and follow the line back to the point of origin?

 

[MavicCF]

This may have already been answered, but I was flying in Active Track when Go4 crashed on my Android phone. So I flipped to sports mode... Nothing! Still in Active Track. I hit pause... Nothing. I had to get the app back up to stop the drone from following me everywhere I walked

Yeah, Robert clarified what he meant back in post #17. Thanks though!

 

[Keule]

Off topic: What is the procedure that you use for adding your signature to your posts (i.e., your equipment)?

In the forum, click on your username, click signature, proceed and edit your desired content.

 

[Mad Mavic]

Anyway, picking a good landmark and paying attention to your surroundings should get you back. I think that link talks mostly about commercial drones being able to fly BVLOS but still it would be cool...

Picking out a landmark is excellent advice MavicCF. As a general aviation pilot, we call that seat of the pants flying. Not sure why but it simply means the pilot is flying without instruments, therefore landmarks are indeed valuable aids to navigation. Not to turn this into a history lesson but barnstormers often only had a compass, no GPS, Transponders, Turn and bank indicators, airspeed indicators, or altimeters. Heck, they didn't even have control towers or controlled airspace. That must have been a blast. take off anywhere and land anywhere... ah what were we talking about LOL

 

[droneuser]

using the controller display and binoculars

 

[Dabrain]

Home lock is on the same screen as the intelligent flight modes, and you're correct, it won't work if you have no RC connection. It WILL still work, however if you just lose video, which is most often what happens first.

If you loose RC connection, RTH will initiate after 3 seconds

 

[jedburgh01]

Hey all

Hypocritical question here..

If you are flying your mavic about 1 mile away and all of sudden you lose GPS mode and it switches to ATTI - how could you return the bird home?

Lots of times I'm flying out over ocean or inland so even a video signal on the phone may not be enough be able to clue together how to get the bird home...what would you do then? in ATTI mode only?

Thanks

Look at the flight track on the map and use that to plot a course home

 

[DJI27]

If you loose RC connection, RTH will initiate after 3 seconds

Very true but for RTH to then work you best hope you still have a connection to GPS satellites.

Without GPS, RTH will not work...

 

[MiniPalourde]

However, the compass should still work, right? So yaw the aircraft around until the arrow is pointing back at you, and then full-throttle forward until it comes back into view. Watch the video feed and avoid any obstacles.

I don't think the map would work at all if GPS was lost. The aircraft wouldn't show where you are