DIVE BOMBED FROM 400ft - because of an add-on

[ac0j]

Not if it's digital...

 

[Lon Denard]

LOL, sometimes, I have an old alarm clock that blinks 12:00 all day long... Its digital!

Ugh you win!

 

[dirkclod]

OK guys lets get back to the topic .

 

[choo choo]

OP, Sounds like a mid flight prop failure with the spiraling down. Sensors would make it stop where it is.

I agree with @sar104 that @choochoo had a bad compass reading from the launch place.

I’ve had a look at the air data readings and everything was normal, no compass problems until it actually crashed, obviously then it showed as a compass error, due to the craft being upside down. The flight path shows it flying backwards and it actually changes direction slightly in time with every flash of the Cree strobe . The flight path isn’t smooth or linear, it has kinks in it, in time with each strobe flash. See pic

 

[John MacAulay]

I have those cree strobons and love them. I don't fly in the dark but use them around dusk sometimes.
Is this something I need to be concerned about? Flight log analysis would sure be good to clear up any confusion for those of us that have purchased these.

 

[choo choo]

Dropbox - Mavic pro - Simplify your life

Here’s a link to the air data if anyone can figure out where it went wrong, in the hope that myself and others can learn from my mistake. Best wishes. Brian

 

[dirkclod]

Thanks choo and sure someone can read them and this has seemed to got off track of the op. Now if @quantumvortex would post his between both of them we could see for if
those lights are going to be an issue.

 

[sar104]

I'm really not sure what to say about this short flight. The attitude and altitude data at the end are certainly very strange:



And then you look at the stick inputs:



The aircraft behaved exactly as instructed, ending with full right aileron, full backwards elevator, full left rudder and full down throttle (an in-flight CSC by the way - had that been enabled). This event had nothing at all to do with strobes - the pilot corkscrewed it into the ground, with impact at 53.1 seconds.

 

[quantumvortex]

Sorry guys,

I havent been able to upload, pics, etc yet, since at work we hardly have access to nothing but I did sync it up on my DJI account (Flight Record).

I could agree with the propeller points you guys made however when I look at the actual replay of the flight I can see it spins multiple times at different flown to locations before it finally "quasar'd" toward earth. So I would think a prop would come off ONCE and then it would not continue to fly and again act as though a prop came off etc.

But again I get the logs, because now that it has settled in I am somewhat pissed and heartbroken since I flew/fly EVERYDAY through 3 batteries at least, EVERYDAY...now its like I've lost a really great buddy or something. ...know what I mean?

 

[sar104]

Sorry guys,

I havent been able to upload, pics, etc yet, since at work we hardly have access to nothing but I did sync it up on my DJI account (Flight Record).

I could agree with the propeller points you guys made however when I look at the actual replay of the flight I can see it spins multiple times at different flown to locations before it finally "quasar'd" toward earth. So I would think a prop would come off ONCE and then it would not continue to fly and again act as though a prop came off etc.

But again I get the logs, because now that it has settled in I am somewhat pissed and heartbroken since I flew/fly EVERYDAY through 3 batteries at least, EVERYDAY...now its like I've lost a really great buddy or something. ...know what I mean?

It did not lose a prop.

 

[choo choo]

I'm really not sure what to say about this short flight. The attitude and altitude data at the end are certainly very strange:

View attachment 50515

And then you look at the stick inputs:

View attachment 50516

The aircraft behaved exactly as instructed, ending with full right aileron, full backwards elevator, full left rudder and full down throttle (an in-flight CSC by the way - had that been enabled). This event had nothing at all to do with strobes - the pilot corkscrewed it into the ground, with impact at 53.1 seconds.

I had absolutely no stick inputs at all, from hover and recording the home point, it just flew backwards in a sort of semi circle until the very last seconds when it was heading towards some houses and cars, so I initiated the CSC. It then came down and as it hit the post, it spun around. I’ve no argument with the fact that it corkscrewed into the ground when I initiated CSC. The issue is WHY did it shoot off backwards with no input from me. If we can find the reason, then we can help others avoid a similar situation.
I’m beginning to be more convinced that the strobes (or their positioning) has something to do with it, mainly due to the slight ‘dog legs’ in the flight, which are at very regular intervals, it may be coincidence but they are in time with the strobe flashes.

 

[ac0j]

I had absolutely no stick inputs at all, from hover and recording the home point, it just flew backwards in a sort of semi circle until the very last seconds when it was heading towards some houses and cars, so I initiated the CSC. It then came down and as it hit the post, it spun around. I’ve no argument with the fact that it corkscrewed into the ground when I initiated CSC. The issue is WHY did it shoot off backwards with no input from me. If we can find the reason, then we can help others avoid a similar situation.
I’m beginning to be more convinced that the strobes (or the positioning) has something to do with it, mainly due to the slight ‘dog legs’ in the flight, which are at very regular intervals, it may be coincidence but they are in time with the strobe flashes.

The log shows entire flight, it flew where the controls sent it. Maybe you wern't moving the sticks, but the RC was sending the commands. I have heard that smart watches or fitness trackers, or magnetic jewelry can effect controls......

 

[sar104]

I had absolutely no stick inputs at all, from hover and recording the home point, it just flew backwards in a sort of semi circle until the very last seconds when it was heading towards some houses and cars, so I initiated the CSC. It then came down and as it hit the post, it spun around. I’ve no argument with the fact that it corkscrewed into the ground when I initiated CSC. The issue is WHY did it shoot off backwards with no input from me. If we can find the reason, then we can help others avoid a similar situation.
I’m beginning to be more convinced that the strobes (or the positioning) has something to do with it, mainly due to the slight ‘dog legs’ in the flight, which are at very regular intervals, it may be coincidence but they are in time with the strobe flashes.

The aircraft behavior mirrored the recorded stick inputs. That's the only data I have to go on. If you want to blame the strobes then I can't help you any further, because, quite apart from there being no flight control mechanism to explain how that could happen, there is no evidence in the data to support such a hypothesis.

 

[abtocmeptb]

Did strobe lights survived?

On a serious note - it’s sucks

 

[sar104]

I had absolutely no stick inputs at all, from hover and recording the home point, it just flew backwards in a sort of semi circle until the very last seconds when it was heading towards some houses and cars, so I initiated the CSC. It then came down and as it hit the post, it spun around. I’ve no argument with the fact that it corkscrewed into the ground when I initiated CSC. The issue is WHY did it shoot off backwards with no input from me. If we can find the reason, then we can help others avoid a similar situation.
I’m beginning to be more convinced that the strobes (or their positioning) has something to do with it, mainly due to the slight ‘dog legs’ in the flight, which are at very regular intervals, it may be coincidence but they are in time with the strobe flashes.

Actually looking earlier in the flight, you did have an uncommanded yaw excursion of 63° CW starting at 44.3 seconds, with a little pitch and roll variation associated with it:



Is that what what caused you to take some rather drastic actions to counteract?

Can you pull the DAT file from the mobile device? That would need a closer look.

 

[choo choo]

Did strobe lights survived?

On a serious note - it’s sucks

Lol. They did survive.
Thanks to sar104 for all time and his help. I was as much at a loss as everyone to explain what happened.
Sooo after a lot of probing the airdata I managed to get a replay of the stick movements, and guess what..for 1.5 seconds I had the reverse stick fully back towards me, at full speed, that would explain why it flew backwards, seemingly out of my control, maybe my fleecy coat flapped and caught on the control, I don’t know, but there it is, my right stick fully back. Having seen it going apparently out of control, I initiated CSC command.
So there we have it, pilot error.
I have had a good few hours flying today with absolutely no issues, in fact I’ve flown her further than I’ve ever done and have complete confidence in her.

 

[Lapeer20m]

A fisherman buddy of mine used these glow in the dark lures. To make the. Glow ultra bright, he would use an old fashioned camera flash just before releasing the line.

I was wearing an analog/digital watch with glow in the dark hands. I thought it would be cool to put the strobe right up to my watch face and pull the trigger.

My watch never worked again. It was completely DOA.

I realize that type of strobe is different than the type used by the op, but the concept of strobes causing electronics to malfunction doesn’t seem too far fetched.

 

[choo choo]

Actually looking earlier in the flight, you did have an uncommanded yaw excursion of 63° CW starting at 44.3 seconds, with a little pitch and roll variation associated with it:

View attachment 50562

Is that what what caused you to take some rather drastic actions to counteract?

Can you pull the DAT file from the mobile device? That would need a closer look.

That about sums it up. It started to move by itself and I attempted to gain some control at 45.9 seconds, which is when my right stick was moved back for 1.4 seconds, either accidentally or intentionally I’m not certain.
I then initiated CSC when it didn’t appear to responding. It’s fairly late here in the UK (10.30pm) and I have to get up at 4am for work. I’ll have a look and see if I can download the data tomorrow. It’ll be intriguing to get to the bottom of this. Thank you for everything. Regards Brian

 

[choo choo]

Actually looking earlier in the flight, you did have an uncommanded yaw excursion of 63° CW starting at 44.3 seconds, with a little pitch and roll variation associated with it:

View attachment 50562

Is that what what caused you to take some rather drastic actions to counteract?

Can you pull the DAT file from the mobile device? That would need a closer look.

 

[choo choo]

Actually looking earlier in the flight, you did have an uncommanded yaw excursion of 63° CW starting at 44.3 seconds, with a little pitch and roll variation associated with it:

View attachment 50562

Is that what what caused you to take some rather drastic actions to counteract?

Can you pull the DAT file from the mobile device? That would need a closer look.

Airdata - A WeTransfer Board

Hope this helps.