Fly away again..

[Photo]

Has anyone of you had a FLY AWAY under the following circumstances:
All calibrations done and OK. You took off with more than 15-16sats locked in angel mode with white flash in purple.
No high buildings, mountains, power lines, etc or GPS / Compass warnings during flight and you didn't fly more than approx 500meters away.
I have NOT.

 

[Dr Delta]

lol

 

[rdonson]

Has anyone of you had a FLY AWAY under the following circumstances:
All calibrations done and OK. You took off with more than 15-16sats locked in angel mode with white flash in purple.
No high buildings, mountains, power lines, etc or GPS / Compass warnings during flight and you didn't fly more than approx 500meters away.
I have NOT.

I think I HAVE. Look at the thread "After Thought...". There was one message about GPS lost as it flew away and I had no control with the sticks at that point. There were NO previous GPS warnings prior to that.

 

[Dougcjohn]

I think I HAVE. Look at the thread "After Thought...". There was one message about GPS lost as it flew away and I had no control with the sticks at that point. There were NO previous GPS warnings prior to that.

Ron, That's a major bummer!
Where you able to see where it went and retrieve? By the way, Did you get your previous tree landed bird returned or still missing? Was this the same area?

Question from my naiveness, does loosing GPS commonly associate to losing RF to the Bird? I would assume you should be able to still fly it ATTI mode.

Again, sorry about the fly away... hope you retreive

 

[rdonson]

Thanks, Doug. You can read the entire saga here: Another thought.......

Bottom line is that it seems only a broken propeller (so far). Based on the exceptional efforts of @Steve Carr in analyzing the data available we can only conclude the GPS module momentarily barfed or we had a solar flare at that moment.

I’ve lost faith in the GPS module and ordered another one. It should arrive today.

 

[Photo]

I think I HAVE. Look at the thread "After Thought...". There was one message about GPS lost as it flew away and I had no control with the sticks at that point. There were NO previous GPS warnings prior to that.

Ron, you Think you have..?. Was all "data" 100% ok as I mentioned in my thread? How can you then lose GPS connection if not a hardware problem? The H and ST16 have a clear sky and the sats are still there..

 

[rdonson]

Ron, you Think you have..?. Was all "data" 100% ok as I mentioned in my thread? How can you then lose GPS connection if not a hardware problem? The H and ST16 have a clear sky and the sats are still there..

As I referenced previously all data was NOT ok. There was a loss of GPS for a minute or two in the telemetry. Enough time for the H to find a pine tree and take up residence 50’ up. @Steve Carr spent a significant amount of his time analyzing and explaining to me what the data showed in the various files. I’m indebted to him for his kindness. We also had a solar event that afternoon that “could” have effected the GPS although I believe that to be unlikely

Bottom line, I lost faith in that GPS module. A new one was delivered today.

P.S. I used the word THINK in my initial response based on how I interpreted your post.

 

[Steve Carr]

Has anyone of you had a FLY AWAY under the following circumstances:
All calibrations done and OK. You took off with more than 15-16sats locked in angel mode with white flash in purple.
No high buildings, mountains, power lines, etc or GPS / Compass warnings during flight and you didn't fly more than approx 500meters away.
I have NOT.

I'll take a stab at this. My comments are speculation. I have no solid basis for my opinion on this matter other than observations and reviews of flight problems.

I believe the H GPS does not update well while in the air regarding satellite almanac data. I think it's important to allow extra time on the ground on the first flight of the day so the data is fully updated prior to liftoff. The satellite count on the display can be misleading. It is merely showing the number of sats that have been located, but it doesn't mean the almanac has finished updating. If you are concerned with this issue then just allow a bit of extra time.

Like many of us, I wish there was a way to quickly turn off GPS. That feature was added to the 520. However, I have yet to see any posts on the 520 which necessitated the use of that feature. Perhaps it's just because there are so many more H's in the air. So with the H your best chance at recovering control is to go max throttle and gain enough altitude so you can turn off the GPS.

 

[Photo]

I'll take a stab at this. My comments are speculation. I have no solid basis for my opinion on this matter other than observations and reviews of flight problems.

I believe the H GPS does not update well while in the air regarding satellite almanac data. I think it's important to allow extra time on the ground on the first flight of the day so the data is fully updated prior to liftoff. The satellite count on the display can be misleading. It is merely showing the number of sats that have been located, but it doesn't mean the almanac has finished updating. If you are concerned with this issue then just allow a bit of extra time.

Like many of us, I wish there was a way to quickly turn off GPS. That feature was added to the 520. However, I have yet to see any posts on the 520 which necessitated the use of that feature. Perhaps it's just because there are so many more H's in the air. So with the H your best chance at recovering control is to go max throttle and gain enough altitude so you can turn off the GPS.

Great answer Steve; I always allow the H idle 12,5 minutes when not in the air for 24hrs to allow almanack update. Many pilots say its not necessary but its a cheap investment to avoid fly aways due to GPS failure.

 

[Steve Carr]

Great answer Steve; I always allow the H idle 12,5 minutes when not in the air for 24hrs to allow almanack update. Many sats its not necessary but its a cheap investment to avoid fly aways due to GPS failure.

I don't think it's related to the number of sats so much as the quality of the signal and the state of the updating. The GPS seems to "freeze" for a few seconds during the updates in flight which confuses the FC. So allowing the updating to finish may avoid the freeze.

 

[Photo]

I don't think it's related to the number of sats so much as the quality of the signal and the state of the updating. The GPS seems to "freeze" for a few seconds during the updates in flight which confuses the FC. So allowing the updating to finish may avoid the freeze.

Agree!

 

[NorWiscPilot]

I don't think it's related to the number of sats so much as the quality of the signal and the state of the updating. The GPS seems to "freeze" for a few seconds during the updates in flight which confuses the FC. So allowing the updating to finish may avoid the freeze.

There is our firmware upgrade wish: an indicator telling the pilot “almanac update complete!”

 

[Photo]

There is our firmware upgrade wish: an indicator telling the pilot “almanac update complete!”

NorWisc, and until this firmware is released we can wait 12.5 minutes before take off, if not in the air for a while. For me that is 24hrs. Then you'll be 99,5% sure that the “almanac update is completed” For that purpose I use a separate battery.

 

[Time Flize]

Has anyone of you had a FLY AWAY under the following circumstances:
All calibrations done and OK. You took off with more than 15-16sats locked in angel mode with white flash in purple.
No high buildings, mountains, power lines, etc or GPS / Compass warnings during flight and you didn't fly more than approx 500meters away.
I have NOT.

I had one yesterday - I have no idea what so ever where the aircraft is!
Aircraft on 3rd battery - all good for 30 seconds then reported critical battery level and auto landed a few metres away. Power down didn't have any effect - and then it decided to take off and disappear over the trees some 1000m away ..... bummer.

I'll go out and try and locate it in the next few days ......

 

[Photo]

I had one yesterday - I have no idea what so ever where the aircraft is!
Aircraft on 3rd battery - all good for 30 seconds then reported critical battery level and auto landed a few metres away. Power down didn't have any effect - and then it decided to take off and disappear over the trees some 1000m away ..... bummer.

I'll go out and try and locate it in the next few days ......

Not good Time Flize. Q's: 1. How many sats did you see before take off? 2. How many minutes with ST16 and H switched on before take-off to secure “almanac update"?
How many days since last flight?

Best from Sweden

 

[Time Flize]

Not good Time Flize. Q's: 1. How many sats did you see before take off? 2. How many minutes with ST16 and H switched on before take-off to secure “almanac update"?
How many days since last flight?

Best from Sweden

Hi

I had 17 sats locked in.
This battery number 3 of 3 one after the other - no breaks other than to fit the next battery.
Prior to yesterday, the previous flight was about 2 weeks ago.

 

[Photo]

Hi again Time F. I know there are many discussions in this subject, but it's strongly recommended to stay idling / Power On, (no motors and motorleds on) on the ground for 12.5 minutes before take-off if you haven't been in the air for one week. You wrote two weeks since your last flight. When you say 17 sats, you DO NOT know they are locked. Only "found", this is a huge difference. 12.5 minutes, (right or wrong) is a very cheap insurance. More here: GPS Time to First Fix (TTFF) Defined

 

[Steve Carr]

I had one yesterday - I have no idea what so ever where the aircraft is!
Aircraft on 3rd battery - all good for 30 seconds then reported critical battery level and auto landed a few metres away. Power down didn't have any effect - and then it decided to take off and disappear over the trees some 1000m away ..... bummer.
I'll go out and try and locate it in the next few days ......

I'd like to see the telemetry from that last flight. It will also show you where to look for the H. If you need help with that please ask.

 

[rdonson]

Hi again Time F. I know there are many discussions in this subject, but it's strongly recommended to stay idling / Power On, (no motors and motorleds on) on the ground for 12.5 minutes before take-off if you haven't been in the air for one week. You wrote two weeks since your last flight. When you say 17 sats, you DO NOT know they are locked. Only "found", this is a huge difference. 12.5 minutes, (right or wrong) is a very cheap insurance. More here: GPS Time to First Fix (TTFF) Defined

I don't disagree but I'm curious where the one week limit on the almanac being able to retain the data comes from. My inquiring mind wants to know.

 

[Photo]

I don't disagree but I'm curious where the one week limit on the almanac being able to retain the data comes from. My inquiring mind wants to know.

Hi Rob, have read it... but can't remember where....I will search and let you know.