My P3P crashed, DJI not cooperating

[Noodle]

Had the phantom calculated the proper altitude it would have never hit that rock.

I said it earlier and my prediction is right about DJI not altering their offer of 20% off. Even if your drone didn't hit that rock, it would still head back to its original home point, which is in the middle of the river, and guess what? You may not even have a drone to be recovered and and no data log to be analysed now. So in the end, your drone is still doomed. May be you should thank the error in the barometer and your drone hit the rock, at least you have the drone in shallow water which you can recover, rather than at the bottom of the river.

 

[Reed L]

Did u miss the entire part of this thread where it's abundantly clear that the Phantom calculated the wrong altitude? The reported altitude at the time of impact was off by over 40 feet. This was certainly a contributing factor in the crash. As I've said before, I did make mistakes, however there is also an element of equipment failure in this crash. Had the phantom calculated the proper altitude it would have never hit that rock.

DJI is refusing to acknowledge any issue with the barometer sensors. Others on the forum have conducted independent testing and have confirmed incorrect altitude measurements after a few minutes of flight.

Nope, I didn't miss it at all, I simply didn't ignore the obvious, you caused the crash. I'm not trying to be harsh, just stating the basic fact. If you would have cancelled RTH or set the RTH point to return to the controller in the first place, it would have never taken off and moved away from you when the low battery warning kicked in the RTH. You let the battery get to low and... had the RTH point set not to where you were... You simply made a bunch of mistakes. To me it looks like DJI has gone above and beyond and given you a discount out of kindness, not because you deserved anything at all from them. Accept the fact,.. you caused the crash yourself. Sorry for your loss - but don't try to pass the buck.

 

[Zuzua]

Sorry buddy but after reading your thread I would have to agree with Reed and others.This entire situation was caused by pilot inexperience, incorrect settings, tunnel vision when rth kicked in, etc etc. Remember that even in full size air crafts things do go wrong and it is the operators duty to be able to correct those situations.
I'm sure you have learnt many valuable points and experience from this that is going to make a better uav pilot. Sorry for the monetary loss!!

 

[MikeyOnline]

I can see both sides. It's not disputed that there was an altitude error but I can see DJI arguing that a number of pilot errors up to the point that RTH engaged was what put you in that position to begin with. So I wouldn't expect 100% coverage. Then it's just down to arguing should it be 20%, 30%, "at cost", etc. I've posted a number of suggestions in this thread where I think DJI can improve upon their RTH logic but that aside, I hate to say it, but while I think you were justified in arguing for better than 20%, at this point if it were me, I'd just eat this one and chalk it up to a learning experience. Flying these things can be expensive unfortunately, and I learn more (mostly about what I shoudln't do) each day. Good luck with whatever you decide.

Mike

 

[Chris_P]

I can see both sides. It's not disputed that there was an altitude error but I can see DJI arguing that a number of pilot errors up to the point that RTH engaged was what put you in that position to begin with. So I wouldn't expect 100% coverage. Then it's just down to arguing should it be 20%, 30%, "at cost", etc. I've posted a number of suggestions in this thread where I think DJI can improve upon their RTH logic but that aside, I hate to say it, but while I think you were justified in arguing for better than 20%, at this point if it were me, I'd just eat this one and chalk it up to a learning experience. Flying these things can be expensive unfortunately, and I learn more (mostly about what I shoudln't do) each day. Good luck with whatever you decide.

Mike

Thanks Mike. Your assessments have always been very fair and impartial and I appreciate your input. I wasn't expecting a full warranty replacement as I also made mistakes. What I find most annoying is DJI's position that the altitude numbers in their flight logs are 100% accurate despite overwhelming evidence to the contrary.

They need to accept that there are some issues here that need to be addressed; the faulty altitude readings and the operator's ability to cancel the ascent on RTH while allowing the aircraft to fly home at a potentially dangerous altitude are the notable issues here. I have been criticized for applying negative throttle after the RTH engaged thus cancelling the altitude rise to my preset level. This all occurred while I was attempting to land the Phantom, the altitude rise was inadvertently cancelled due to my throttle inputs for landing.

I also found their customer service to be dreadful. Probably the worst company I've ever dealt with. They may manufacture great technology but they fail miserably in the customer service and support departments.

 

[impilot51]

They need to accept that there are some issues here that need to be addressed.

I believe that they are accepting some responsibility. 20% of it to be precise. Based on the number of errors that you made and the fact that the whole thing could have been easily avoided had a more experienced pilot been at the controls, I think they are being quite fair. Frankly, I'm surprised they offered you any discount. Face it. You were a new pilot in a complicated situation that did not understand RTH. Things went south, you crashed. Own it.


Sent from my iPad using PhantomPilots mobile app

 

[mikesmiley]

THIS! THIS RIGHT HERE!

Nineteen pages, and this one post makes it all worthwhile. Why? Because it's the truth, and it works.

Before reading this one post and trying it, I had variations of well over ten feet between taking off and landing.

Thank you, GadgetGuy.

Bladestrike, a respected DJI employee who used to help out and post here, has previously stated that accurate barometer readings, which are always relative to your launch point, require a 3 minute warmup period on the ground, to properly calibrate the barometer. He recommended using a spare battery just for that purpose, and then replacing that battery with a fully charged one just before takeoff. The barometer calibration, the IMU warmup, and the satellite lock will survive the reboot during the battery swapout, enabling flying almost immediately. As soon as the Home Point is recorded, you can take off, with a properly calibrated barometer. If you don't allow sufficient time for the barometer to calibrate before takeoff, the readings won't be accurate.

 

[MikeyOnline]

THIS! THIS RIGHT HERE!

Nineteen pages, and this one post makes it all worthwhile. Why? Because it's the truth, and it works.

Before reading this one post and trying it, I had variations of well over ten feet between taking off and landing.

Thank you, GadgetGuy.

This whole thing is one big gray area for me. This entire thread brings up more questions than answers for me.

(1) Where in the manual does it state that you need to bring a spare battery to warm up the barometer for 3 minutes to obtain a reasonably accurate altitude, ignoring all "ready to fly" messages and ignoring that the takeooff point reads (correctly) 0 ft altitude?
(2) I've tried it, warmed mine up for 3 minutes, and still ended up with a 15-20 foot discrepancy in altitude between takeoff and landing on even a short 6 minute flight.
(3) Where in the manual does it warn you that if you happen to be desending at the time RTH is called for, that between altitude errors and RTH height cancellation, you could RTH at as low as 5 meters altitude?

My only epiphany from this thread is that (1) pilots have to be aware of a lot more than is listed in the manual and (2) DJI should really improve some of their logic, specifically to ignore any stick input within say 10 seconds of initiation of RTH and (2) not trying to fly to the home point if the AC is descending and the controller is currently within say 50m of the current AC location and the home point is significantly further than the controller location. Simply put, pilot errors were significant in this crash but I still believe that DJI should be doing whatever it can to reduce the probability of a crash due to silly logic like canceling RTH altitude when the AC is already descending at the point of RTH initiation and choosing to RTH to a point that is miles beyond the current controller location.

I did read that moving the sticks after the AC had reached 20m could result in the RTH height being cancelled. But I never knew that between inaccurate altitude readings and being in a descent at the time RTH was initiated could result in the AC flying into a tree, rock, whatever at under 5m was a possibility... unless maybe you take a spare battery and warm up the barometer/altimeter 3 minutes past when the app reads "good for takeoff". Try finding that one in the manual! For me... all good. I know now. For the OP, he's out $500. So the only thing that bothers me, is that I (and I bet a few others) get to learn these facts at the Chris' expense.

Mike

 

[GadgetGuy]

Here are some other things that contributed to the crash:

• You did not disable Smart RTH prior to takeoff
• You did not cancel RTH when you were prompted to do so
  
• You moved the throttle stick while your Phantom was trying to ascend to your set RTH altitude
• After your Phantom started returning home, you gave it full throttle down (instead of up) and descended toward the rocks

I'll add one more, which hasn't been properly addresssed. The pilot "thought" he was resetting his Home Point to the Tx location several times during the flight, and yet the Home Point steadfastly remained at the default of his original takeoff location. The pilot ALSO ignored the app warnings that the Home Point was unable to be reset EACH TIME he attempted to reset it. This begs the question of whether the pilot ever had the ability to even change the Home Point to the transmitter location. That ability requires several preconditions. There is no GPS in the P3 remote. To use GPS for resetting the Home Point to the transmitter location, the tablet itself must supply the GPS to the transmitter, to relay the change of the Home Point to the aircraft. The only tablets that have built-in GPS are cellular iPads, cell phones, and some Android tablets. A WiFi only iPad can also be paired with an external Bluetooth GPS device, such as a Bad Elf or similar device to supply GPS without an internal GPS antenna. What method was the OP attempting to use which failed 100% of the time? My guess is a tablet without any GPS at all, which would be yet another pilot error. Otherwise, why did his attempted resets of the Home Point to the transmitter location fail 100% of the time?

 

[Meta4]

The only tablets that have built-in GPS are cellular iPads, cell phones, and some Android tablets.

Update ... most Android tablets have GPS built in

What method was the OP attempting to use which failed 100% of the time? My guess is a tablet without any GPS at all, which would be yet another pilot error. Otherwise, why did his attempted resets of the Home Point to the transmitter location fail 100% of the time?

If you don't have GPS on the tablet or the tablet GPS has no signal and you try to reset home to the current location, you get an error message like this.

You can also confirm that home has been changed by referring to the distance data at the bottom of the screen.

 

[Chris_P]

I was using an iPad Air2 LTE with full GPS and Internet access. When I replay the flight on the iPad DJIGO app, I can see my location updated at certain intervals. Yet another mystery why the home point didn't update during the flight.

I am a relatively new operator but I did my due diligence in educating myself before flying this aircraft. I read numerous posts on this forum about RTH disasters and I took action to avoid that. I set my go home attitude to 30M to avoid the very thing that ended up happening. I also read about updating my RTH location if I stray from the takeoff location and I knew I needed a GPS enabled device to do that so I went out and got the proper device.

Yes, mistakes were made but not all of them due to lack of knowledge. There was some dumb luck blended in as well.

 

[GadgetGuy]

I was using an iPad Air2 LTE with full GPS and Internet access. When I replay the flight on the iPad DJIGO app, I can see my location updated at certain intervals. Yet another mystery why the home point didn't update during the flight.

I am a relatively new operator but I did my due diligence in educating myself before flying this aircraft. I read numerous posts on this forum about RTH disasters and I took action to avoid that. I set my go home attitude to 30M to avoid the very thing that ended up happening. I also read about updating my RTH location if I stray from the takeoff location and I knew I needed a GPS enabled device to do that so I went out and got the proper device.

Yes, mistakes were made but not all of them due to lack of knowledge. There was some dumb luck blended in as well.

My apologies. I stand corrected about my assumption regarding your tablet. I'll go back to my original suggestion for you. Turn OFF Smart Return Home. Had it been OFF, instead of ON, none of this would have happened, and you would have simply completed your responsible hand catch.

 

[Chris_P]

Agreed. That was for sure my biggest mistake. Lesson learned.....

 

[mikesmiley]

This whole thing is one big gray area for me. This entire thread brings up more questions than answers for me.

(1) Where in the manual does it state that you need to bring a spare battery to warm up the barometer for 3 minutes to obtain a reasonably accurate altitude, ignoring all "ready to fly" messages and ignoring that the takeooff point reads (correctly) 0 ft altitude?
(2) I've tried it, warmed mine up for 3 minutes, and still ended up with a 15-20 foot discrepancy in altitude between takeoff and landing on even a short 6 minute flight.
(3) Where in the manual does it warn you that if you happen to be desending at the time RTH is called for, that between altitude errors and RTH height cancellation, you could RTH at as low as 5 meters altitude?

My only epiphany from this thread is that (1) pilots have to be aware of a lot more than is listed in the manual and (2) DJI should really improve some of their logic, specifically to ignore any stick input within say 10 seconds of initiation of RTH and (2) not trying to fly to the home point if the AC is descending and the controller is currently within say 50m of the current AC location and the home point is significantly further than the controller location. Simply put, pilot errors were significant in this crash but I still believe that DJI should be doing whatever it can to reduce the probability of a crash due to silly logic like canceling RTH altitude when the AC is already descending at the point of RTH initiation and choosing to RTH to a point that is miles beyond the current controller location.

I did read that moving the sticks after the AC had reached 20m could result in the RTH height being cancelled. But I never knew that between inaccurate altitude readings and being in a descent at the time RTH was initiated could result in the AC flying into a tree, rock, whatever at under 5m was a possibility... unless maybe you take a spare battery and warm up the barometer/altimeter 3 minutes past when the app reads "good for takeoff". Try finding that one in the manual! For me... all good. I know now. For the OP, he's out $500. So the only thing that bothers me, is that I (and I bet a few others) get to learn these facts at the Chris' expense.

Mike

I don't have an answer to all of that. All I can say is that after reading this and trying it, I can fly a 27,000' mission, and upon landing where I took off from, my displayed altitude is within 2.5' of actual.

 

[henick]

Well on a boat RTH would be set to hover if the bird belonged to me. Don't care what anybody else does.

 

[CCDD]

After all of this Chris, I'd like to know if you're going to stick with DJI and buy another with your 20% off coupon?

 

[Noodle]

After all of this Chris, I'd like to know if you're going to stick with DJI and buy another with your 20% off coupon?

Or plan B

 

[Avocet]

Or plan B

Well now ... 2 driver's side tires with punctures? In my neck of the woods that's easily another $400 ... strangely, I expected to cringe when I saw this (but didn't???) ... I thought he was far too controlled wielding that hammer. Perhaps he dumped his AC into a lake or something and had his fun making this video! Might explain why the RC was not a player in the vid.

Is this an anger management solution or issue?

Yowza

 

[Chris_P]

After all of this Chris, I'd like to know if you're going to stick with DJI and buy another with your 20% off coupon?

To be honest, I haven't decided yet. It's not about the money at this point. Their lousy offer is worthless to me because I can easily get a new P3P on sale with the remote and charger for not a whole lot more. My current Phantom still works fine, I can replace the camera for around $350 and I'm back in business. I've had her out a few times in controlled environments and everything seems fine.

Trust me, I've been researching the competition and DJI still has the most features for the price point. They obviously know that, hence they feel they can treat their customers like crap. It's not even the 20% that bothers me, it's the the lack of communication. I would have expected someone to speak to me and explain their findings, explain how they arrived at 20% and at least pretend to give a **** about keeping me as a DJI customer. I've heard nothing !

 

[CCDD]

You're right Chris, although there is competition out there, I've yet to find anything available that delivers the "whole" package like a Phantom. Others are closing in yet not quite there just yet.