P4v2 - Sudden and Permanent Disconnect & Vanish

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As an aside - last night I installed Google Earth on my PC, then uploaded the .kmz from my flight record into it.

I highly recommend this, especially if you have a particular flight you liked or want to study again.

Wish I’d known about it long ago. It’s pretty wicked!
 
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Just got back from my 10th time out. Some of the area searched today was for the second or 3rd time. I really appreciate the interest and advice from this forum, so I do wish I had better news.
Alas, I just do not.
Is it possible that someone found it in their back yard and it is being kept nice and comfy in a house somewhere?
 

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The data shows that your max. speed was nearly 40 mph.
The max speed for this flight was 29.3 mph

Is that possible?
In P-GPS mode with obstacle avoidance disabled, the drone can fly at 36 mph.
With a strong tailwind, it can go a little faster, getting close to 40 mph.
But in atti mode with a tailwind, it can fly a lot faster.
i-9TZdcsf-M.jpg
 
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The max speed for this flight was 29.3 mph


In P-GPS mode with obstacle avoidance disabled, the drone can fly at 36 mph.
With a strong tailwind, it can go a little faster, getting close to 40 mph.
But in atti mode with a tailwind, it can fly a lot faster.
i-9TZdcsf-M.jpg
68.7 mph! Woah.
But...

I'm afraid I've got you beat.
 

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Meta4

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I'm afraid I've got you beat.
The problem with that calculation is the assumption that the falling Phantom accelerates at 32 ft/sec²
Analysis of flight data from several Phantoms that fell without losing power has shown that they quickly reach a terminal velocity of 35-40 mph due to air resistance which you haven't allowed for.
The terminal velocity varies as the drone tumbles and air resistance changes with the varying cross sectional area it's acting on.
 
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Hi @Tap2FlyCommode ,

I took a look on the CSV files.

The CSV of the last flight (when you lost the bird):
1st thing I've noticed is that you've started to push the Throttle (see rc_throttle column) after just 0.7 seconds following motors start !!
At 9.0 seconds you were up at 153 ft having just 5 (five) satellites !!
The bird acquired its GSP position just at 11.9 seconds, but at that time you were already up in the sky at 223 ft !!
At 16.3 seconds when the system confirmed Home Point Recorded you were up at 325 ft !!
Don't take me wrong, but this shows a bit nervous behaviour to the bird, and an impacient way to fly. Following the motors start, normally you should wait at ground to see the Home Point Recorded and lift up just if you have at least 12 satellites.

The column "isVideo" flag: did you had 3 unsuccessfull attempts to start video recording at 01:55.8 - 01:57.8 (2 seconds), at 03:44.4 - 03:45.8 (1.4 seconds), at 05:10.2 - 05:12.8 (2.6 seconds), and succeded at 06:00.4 - 06:26.2 (~26 seconds, that being last available data), or something went wrong inside the bird ?

The CSV from the 2nd last flight (the successfull one):
There is a strange matter, the column "gpslevel" is steady zero no matter if the bird has seen or not 1-18 satellites. Normally this level should raise to say at least 3-4 for 12 sats and further higher to 5 for more sats.

I'm wishing you to find the bird, so to have the opportunity to analize the DAT file, that will tell us what happened after you've lost the aircraft downlink. Since the last known isVideo flag was on 1, I guess it means finding the bird will let you see too the video that was recorded beyond you've lost contact.
 
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Hi @Tap2FlyCommode ,

I took a look on the CSV files.

The CSV of the last flight (when you lost the bird):
1st thing I've noticed is that you've started to push the Throttle (see rc_throttle column) after just 0.7 seconds following motors start !!
At 9.0 seconds you were up at 153 ft having just 5 (five) satellites !!
The bird acquired its GSP position just at 11.9 seconds, but at that time you were already up in the sky at 223 ft !!
At 16.3 seconds when the system confirmed Home Point Recorded you were up at 325 ft !!
Don't take me wrong, but this shows a bit nervous behaviour to the bird, and an impacient way to fly. Following the motors start, normally you should wait at ground to see the Home Point Recorded and lift up just if you have at least 12 satellites.

The column "isVideo" flag: did you had 3 unsuccessfull attempts to start video recording at 01:55.8 - 01:57.8 (2 seconds), at 03:44.4 - 03:45.8 (1.4 seconds), at 05:10.2 - 05:12.8 (2.6 seconds), and succeded at 06:00.4 - 06:26.2 (~26 seconds, that being last available data), or something went wrong inside the bird ?

The CSV from the 2nd last flight (the successfull one):
There is a strange matter, the column "gpslevel" is steady zero no matter if the bird has seen or not 1-18 satellites. Normally this level should raise to say at least 3-4 for 12 sats and further higher to 5 for more sats.

I'm wishing you to find the bird, so to have the opportunity to analize the DAT file, that will tell us what happened after you've lost the aircraft downlink. Since the last known isVideo flag was on 1, I guess it means finding the bird will let you see too the video that was recorded beyond you've lost contact.
I would not argue with your assessment at all. I've been flying a while, so I do do things fast. (yep, I said ?). I got no thrill out of taking unnecessary risks with it, or flying fast. I do like to get good footage, at opportune times, so... yes, I got to the location ASAP.

Perhaps I did cause it to turn into a Phantom missile.

Looks like I will never know, but I think there is validity to what you're saying. I will take my time linking in the future. When or if I get another.
 
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Is it possible that someone found it in their back yard and it is being kept nice and comfy in a house somewhere?
Absolutely...I had a few mishaps. all with great endings. found drone under the hands of cooperating folks willing to return the bird no damages.
 

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1st thing I've noticed is that you've started to push the Throttle (see rc_throttle column) after just 0.7 seconds following motors start !!
At 9.0 seconds you were up at 153 ft having just 5 (five) satellites !!
The bird acquired its GSP position just at 11.9 seconds, but at that time you were already up in the sky at 223 ft !!
At 16.3 seconds when the system confirmed Home Point Recorded you were up at 325 ft !!
It's always good to wait for the home point to be recorded, but in this incident, the OP launched and only applied throttle and rudder before the home point was recorded 16.3 seconds later.
This could not possibly have contributed to the incident.
As he had only climbed vertically from launch, the recorded home point would have been quite close to the launch point.
 
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It's always good to wait for the home point to be recorded, but in this incident, the OP launched and only applied throttle and rudder before the home point was recorded 16.3 seconds later.
This could not possibly have contributed to the incident.
As he had only climbed vertically from launch, the recorded home point would have been quite close to the launch point.
"The home point has been updated please check it on the map."
 
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