Phantom throttled down without reason? FLYAWAY?

[lightingbryan]

Randomly yesterday I was flying. I had marked the home location and had decent GPS 7-11. I was flying in a valley in the mountains. Suddenly without notice the Phantom 2 (running 3.02 started to decend. I quickly throttled up (as I was only 20 feet up). The heli partly landed on a rock with one skid. It was a slow decent. After touching the rock I gained control of roll and maneuvered away from the boulder and it landed on the flat ground. Batt at 32% I switched the battery and moved on.

I can only figure the GPS went out and it some how went into land mode as GPS home land was unavailable.
What I should have done was switch to ATTI but it was quick and it was my first real issue/emergency.

Any thoughts on why this happened and anything to check to make sure this doesn't happen again?

 

[sar104]

Randomly yesterday I was flying. I had marked the home location and had decent GPS 7-11. I was flying in a valley in the mountains. Suddenly without notice the Phantom 2 (running 3.02 started to decend. I quickly throttled up (as I was only 20 feet up). The heli partly landed on a rock with one skid. It was a slow decent. After touching the rock I gained control of roll and maneuvered away from the boulder and it landed on the flat ground. Batt at 32% I switched the battery and moved on.

I can only figure the GPS went out and it some how went into land mode as GPS home land was unavailable.
What I should have done was switch to ATTI but it was quick and it was my first real issue/emergency.

Any thoughts on why this happened and anything to check to make sure this doesn't happen again?

What was the Phantom doing when that happened? For example, hover, level flight at constant speed, accelerating, decelerating, changing direction, climbing, descending etc.?

 

[lightingbryan]

Randomly yesterday I was flying. I had marked the home location and had decent GPS 7-11. I was flying in a valley in the mountains. Suddenly without notice the Phantom 2 (running 3.02 started to decend. I quickly throttled up (as I was only 20 feet up). The heli partly landed on a rock with one skid. It was a slow decent. After touching the rock I gained control of roll and maneuvered away from the boulder and it landed on the flat ground. Batt at 32% I switched the battery and moved on.

I can only figure the GPS went out and it some how went into land mode as GPS home land was unavailable.
What I should have done was switch to ATTI but it was quick and it was my first real issue/emergency.

Any thoughts on why this happened and anything to check to make sure this doesn't happen again?

What was the Phantom doing when that happened? For example, hover, level flight at constant speed, accelerating, decelerating, changing direction, climbing, descending etc.?

Hovering mostly. I wasn't moving much when it happened.

 

[lightingbryan]

PS, when I throttled up it didn't do anything.

 

[KG4MXV]

In the assistant software I would check to see what you have the battery limits set for.

 

[sar104]

In the assistant software I would check to see what you have the battery limits set for.

That would do it, but if the battery was at 32% then it was too early - it won't auto-descend until critical level, which I think cannot be set higher than 20%.

 

[lightingbryan]

In the assistant software I would check to see what you have the battery limits set for.

15/30

 

[Ozzyguy]

Perhaps check what your failsafe default is. It sounds like it might be set to landing instead of go home and land. Also in a valley you may have lost all gps signal. In this case the Phantom will land where it is if you lost radio control. This sounds like a likely scenario to me considering your location.

 

[lightingbryan]

Perhaps check what your failsafe default is. It sounds like it might be set to landing instead of go home and land. Also in a valley you may have lost all gps signal. In this case the Phantom will land where it is if you lost radio control. This sounds like a likely scenario to me considering your location.

I was standing 20 feet away. It's set to go home - land.

 

[OI Photography]

Any chance you accidentally bumped it to manual mode? That can cause a sudden unexpected drop in altitude like that which feels like a loss of throttle.

 

[lightingbryan]

Any chance you accidentally bumped it to manual mode? That can cause a sudden unexpected drop in altitude like that which feels like a loss of throttle.

I don't have manual set as a preset. My x1 is set to GPS|ATTI|Go Home

 

[Ozzyguy]

You can lose control signal at any range. Many valleys have mountains at the top of them with powerful transmitters on top. Regardless of if your Phantom is set to go home and land it will land where it is if it can no longer determine where home is.Just curious why you asked for suggestions if your not willing to entertain any of the possibilities throw up.

 

[lightingbryan]

You can lose control signal at any range. Many valleys have mountains at the top of them with powerful transmitters on top. Regardless of if your Phantom is set to go home and land it will land where it is if it can no longer determine where home is.Just curious why you asked for suggestions if your not willing to entertain any of the possibilities throw up.

The suggestions are GREAT! Is there anything wrong with clarifying the situation? Suggesting that I switched it into manual is a great suggestion, but it doesn't solve the issue if the controller can't be put in manual because its not programmed that way. Sorry if the short answers seem negative but I didn't feel like I needed to respond with more of an explanation for a simple suggestion.

So if my controller lost signal 20 feet from the Phantom how do I diagnose that and keep it happening in the future. PS there is no antennas in the area. There is not even power. We were 10 miles from the nearest anything, and no one on multiple cell phone companies had signal. Great suggestion though.

 

[Ozzyguy]

Hmmm its a tricky one thats for sure. All i can suggest is avoid that location and see if i happens under any other conditions. not Ideal I know!

 

[lightingbryan]

Hmmm its a tricky one thats for sure. All i can suggest is avoid that location and see if i happens under any other conditions. not Ideal I know!

That's actually really good advice! If it happens again especially with my batt 2. I will start to get a little worried! It was terrifying for sure! It's just perplexing me since I have studied all the reasons as to why it would trigger land now. I wondered if it was triggered home but it thought it was landing home but was actually 50 off.