@BudWalker ..Hmmm....Something else happened just before the Nav Health Drop....Why would the motors stop reporting for so long??? There is more data missing as well, but that was the most obvious.
A Lucky Day!
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No. Could it be the wrong dat file? Because the date of dat file and flight log is not the same.
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Interesting! The date of the following .dat files is the same as the date of the flight log. One of these files may be the dat file we are looking for.
19-10-04-05-06-48_FLY532.DAT
drive.google.com
19-10-04-04-47-15_FLY531.DAT
drive.google.com
@OOO ....Just so he knows @BudWalker FLY352 is the correct .dat. The GPS dropout shows there as well. Immediately followed by the hdop going to max. This lasted almost prcisely one second before the GPS recovered.
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It seems that something is wrong with GPS unit. May I ask what hdop stands for? One more question, do you see any user/piloting error in this flight. Thank you for all your efforts to clarify the situation.
So, this was all caused by a problem with the GPS unit. More specifically, the hDOP went to the max value which caused the FC to reduce navHealth to 1 then 0.
Also, numSats went to 0 after hDOP maxed out. It's not clear to me if the numSats actually went to 0. It's possible that the GPS unit or the FC could have set the numSats to 0.
The following is from the eventLog stream suggests the GPS unit encountered a HW problem
520.756 : 28543 [L-GPS]<GPS ERROR>m8_check_hash_failed[1] gps [0][0]||
:
520.880 : 28550 [L-FDI]NS(0) GPS(0): fault on , abrupt
:
521.080 : 28560 [L-FDI]NS(0) GPS(0): fault off, abrupt
@OOO this is clearly a HW issue and not a pilot error. As for your question regarding hDOP @Fly Dawg knows more about this than I do.
Also, numSats went to 0 after hDOP maxed out. It's not clear to me if the numSats actually went to 0. It's possible that the GPS unit or the FC could have set the numSats to 0.
The following is from the eventLog stream suggests the GPS unit encountered a HW problem
520.756 : 28543 [L-GPS]<GPS ERROR>m8_check_hash_failed[1] gps [0][0]||
:
520.880 : 28550 [L-FDI]NS(0) GPS(0): fault on , abrupt
:
521.080 : 28560 [L-FDI]NS(0) GPS(0): fault off, abrupt
@OOO this is clearly a HW issue and not a pilot error. As for your question regarding hDOP @Fly Dawg knows more about this than I do.
Nope. I just look at the signal status. I have no idea what it means. ( You showed me that a while back
I thought you might....) But agreed it does appear to be a hardware issue. I saw no pilot issues..I thought you were the GPS expert..... Anyway hDOP is horizontal Dilution of Precision. It's derived from the geometric position of the satellites. The more spread the better the accuracy.Nope. I just look at the signal status. I have no idea what it means. ( You showed me that a while back
Dilution of precision (navigation) - Wikipedia
Well, that explains it a little better but I do have one question. Why does the .txt log indicate the incorrect .dat in CSVview? I have not seen that before. That threw me off a bit. ?
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@Fly Dawg and @BudWalker:
I'll take the drone to a local repair service as soon as possible and share the results with you here. Again many thanks!
I'll take the drone to a local repair service as soon as possible and share the results with you here. Again many thanks!
RodPad
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Well I'm sure glad I kept prodding you on retrieving and sharing your data. 
I learned a lot from this thread and the others, not sure if know any more, but there is a GPS hardware problem on the P4s. I can't tell from the picts what is the defect. So I don't know if others that want to look inside there P4s are going to know what to look for?
For sure they don't have to look inside if they use the flight log viewer. I'm guessing that .5 seconds of zero satellites wasn't long enough to prompt a warning message.
Rod
I learned a lot from this thread and the others, not sure if know any more, but there is a GPS hardware problem on the P4s. I can't tell from the picts what is the defect. So I don't know if others that want to look inside there P4s are going to know what to look for?
For sure they don't have to look inside if they use the flight log viewer. I'm guessing that .5 seconds of zero satellites wasn't long enough to prompt a warning message.
Rod
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Well I'm sure glad I kept prodding you on retrieving and sharing your data.
I learned a lot from this thread and the others, not sure if know any more, but there is a GPS hardware problem on the P4s. I can't tell from the picts what is the defect. So I don't know if others that want to look inside there P4s are going to know what to look for?
For sure they don't have to look inside if they use the flight log viewer. I'm guessing that .5 seconds of zero satellites wasn't long enough to prompt a warning message.
Rod
After this event, I had a few more flights. On most of these flights, I encountered the same problem at unexpected times. I knew there was a problem but I didn't care much about it. If I hadn't brought this up, maybe the drone would have crashed after a while. I really want to thank you all.
For me, take-home messages from this event; 1) if your drone exhibits unusual behavior at unexpected times, be sure take it seriously, 2) you don't have to know everything, as long as you know who to consult
RodPad
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RodPad
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Which videos did you look at? Mine? Most of the footage from my last video were captured after this event and with the same drone. I was really lucky. I’ve already ordered a new GPS unit.
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