What's your minimum # of satellites before taking off?

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Attempted to fly somewhere new today. My satellite # was lower than usual for me and for the first time got the " Ready to Go(vision only)" up top. Satellite # was at about 6. Usually I'm at about 12- 15.

My question is does everyone have a minimum number of satellite that they prefer to see before take off? The "Ready to Go(vision only)" had me super hesitant in taking off.

Thanks!
 
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I never take off with less than seven satellites.
 
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My question is does everyone have a minimum number of satellite that they prefer to see before take off?
There is no simple, single number that ensures that you have GPS, but the minimum is 6.
But as well as a minimum number, you also have to have a suitable spread of satellites.
If the sats are bunched or in a line, you cannot get a good location fix.
The flight controller will assess the satellites visible and determine when it is satisfied that you are getting good location data
That's when you get green.


Attempted to fly somewhere new today. My satellite # was lower than usual for me and for the first time got the " Ready to Go(vision only)" up top. Satellite # was at about 6. Usually I'm at about 12- 15.
The "Ready to Go (vision only)" had me super hesitant in taking off.
If the banner said Ready to Go (Vision Only), you did not have GPS at all.
Launching with brown, you only had the downward sensors to hold position and did not have any homepoint recorded.
If you continued to climb beyond the range of the sensors (10 metres) without getting green, the drone would be in atti mode and drift with the wind.

If you want a home point and GPS position holding, wait for green before launching.
If you are out in the open and the GPS receiver has a clear view of most of the sky, you should always have more sats than you need.
 
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My comfort level used to be 7 to 9 satellites with my old P2V+. But these days with my P4P usually locking onto around 14 satellites, my comfort level is now in the greater than 10 range.
 
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There is no simple, single number that ensures that you have GPS, but the minimum is 6.
But as well as a minimum number, you also have to have a suitable spread of satellites.
If the sats are bunched or in a line, you cannot get a good location fix.
The flight controller will assess the satellites visible and determine when it is satisfied that you are getting good location data
That's when you get green.



If the banner said Ready to Go (Vision Only), you did not have GPS at all.
Launching with brown, you only had the downward sensors to hold position and did not have any homepoint recorded.
If you continued to climb beyond the range of the sensors (10 metres) without getting green, the drone would be in atti mode and drift with the wind.

If you want a home point and GPS position holding, wait for green before launching.
If you are out in the open and the GPS receiver has a clear view of most of the sky, you should always have more sats than you need.
Awesome. Ok got it . Thanks for that explanation!
 
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Attempted to fly somewhere new today. My satellite # was lower than usual for me and for the first time got the " Ready to Go(vision only)" up top. Satellite # was at about 6. Usually I'm at about 12- 15.

My question is does everyone have a minimum number of satellite that they prefer to see before take off? The "Ready to Go(vision only)" had me super hesitant in taking off.

Thanks!
Four satellites is all that is "required" for a GPS position. We don't launch unless we have good geometry on at least twelve satellites. We are generally locked on to 16+ on a normal day under ideal conditions. I am a commercial operator with a mid-grade UAS (+$20,000.00). For recreational flights on a standard low price UAS I would recommend no less than 10 satellites.
 
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I usually fly with 11 sats or more but don't need any if you fly VLOS (but who does vlos anyway) !! 🤣
 
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Usually at least 11 but several times I started with 9 and get more satellites after gain some altitude. Usually it quickly comes to 14 or 16.
But I always wait to hear that the HP has been located. Having no HP is pretty risky situation.
 
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Depends on situation. For example,, I was doing a job between two building that limited satellite acquisition. Part of the job, I shot in vision mode. It was not until I got around 5 stories high that I acquired satellites and got the green status.
 
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Four satellites is all that is "required" for a GPS position.
Four satellites is all that's required to provide a 3D GPS fix (if the geometry is good) but DJI enforce a 6 minimum to provide an additional safety margin.
For recreational flights on a standard low price UAS I would recommend no less than 10 satellites.
If you are flying in the open, you'll always have many more sats than needed.
There's really no need for a self imposed minimum as long as the app gives you green and your drone is out in the open.
 
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I wait for HP, then launch, go up 20 feet and wait for a few seconds and see the sats climb. Been doing this since the P2 days (they were sometimes wobbly with GPS) and not had a problem yet.
A
 
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Attempted to fly somewhere new today. My satellite # was lower than usual for me and for the first time got the " Ready to Go(vision only)" up top. Satellite # was at about 6. Usually I'm at about 12- 15.

My question is does everyone have a minimum number of satellite that they prefer to see before take off? The "Ready to Go(vision only)" had me super hesitant in taking off.

Thanks!
I'm from Trinidad in the caribbean and I sometimes go in the forrest with my spark so satellite lock is limited. If I don't see 10-12 I'm not flying. Better safe than sorry...just got a p4pro and won't use less than 14 Sats to fly
 
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The situation in the forest is specific as you'll get enough number of satellites when you get over trees tops.
If no wind you can easily start with ATTI mode and when you high enough switch to P mode and wait till HP is located.
 
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The situation in the forest is specific as you'll get enough number of satellites when you get over trees tops.
If no wind you can easily start with ATTI mode and when you high enough switch to P mode and wait till HP is located.
Not the places I go....not much clearing to get above and there's usually heavy winds
 
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My question is does everyone have a minimum number of satellite that they prefer to see before take off? The "Ready to Go(vision only)" had me super hesitant in taking off.
I prefer to wait until I have the H mark correctly placed on the screen. Sometimes when the H appears it is way out of the correct home position and that is a security risk.
Esa
 
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Depends. If I'm in a hurry, zero. I'll get to where I need to be in ATTI mode. The drone actually acquires satellites faster in the air (with no obstructions) anyway. She usually has 9 or more satellites by the time I reach my first waypoint.

D
 
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ianzone

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My patience has got better with age so I wait now for it to do its thing,30 sec tops and go to go..6 at the least
 

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