Lost P3a during litchi waypoint mission
- Thread starter gmtjr1115
- Start date
It will allow download of the Airdata csv, but not the original log - still shows insufficient permissions. You do need at least a gold Airdata account to allow that. Alternatively you could just post the csv log directly here.
Airdata UAV - Flight Data Analysis for Drones this is the profile link this is all I have until I can get my tablet onto my pc to extract the data off that. Hopefully there’s more there since there’s basically nothing in the airdata right now. Even if I don’t ever find it I would like to know what Happened. If it ever even initiated RTH, if it just landed after 10% on way back. Or if it just flew away... my phantom has always came back or atleast shown the location If it didn’t come back.
OK - well even without the mission profile, the mission was marginal based on your description and the wind conditions (19 mph W). The outbound leg (2.64 miles), at 25 mph, should have taken around 6 minutes. The return leg, with an airspeed of less than 30 mph (≤ 25° pitch) could have taken up to 20 minutes. That's a total of 26 minutes - more than the rated flying time at optimal speed, not maximum speed.
I don't think it had enough battery to complete the mission, and it likely auto landed well short of returning home.
I don't think it had enough battery to complete the mission, and it likely auto landed well short of returning home.
Based on this mission not able to be completed due to battery life and loss of signal and using litchi with smart return on. Would you start the search based on where it fell short starting from the turn around point of the mission or distance from home. I didn’t explain that right but maybe you understand lol
It really depends quite sensitively on data that we don't have - specifically battery drain rate and wind speed on the return leg. About the only suggestion I would have is to start looking east from the point at which it disconnected on the way out, since if it had returned much past that point you would have expected it to have reconnected.
Probably just repeating things but by my calculations the groundspeed of the AC would be:
25.3 MPH (zero wind) 2226.4 feet/minute
33.6 MPH ( max speed with tailwind)= 2956.8 feet/minute
6.6 MPH (ground speed with18.7 MPH headwind)= 580 feet/minute
Assuming 1/3 of the flight (9294') in each wind condition time it would take to fly in each condition is:
Zero wind= 4.17 minutes
Tailwind =3.14 minutes
Headwind=16.02 minutes
I cant tell the wind direction relative to your actual flight but hope this helps you.
I'm guessing you ran out of battery. I don't fly when the wind is 18MPH.
25.3 MPH (zero wind) 2226.4 feet/minute
33.6 MPH ( max speed with tailwind)= 2956.8 feet/minute
6.6 MPH (ground speed with18.7 MPH headwind)= 580 feet/minute
Assuming 1/3 of the flight (9294') in each wind condition time it would take to fly in each condition is:
Zero wind= 4.17 minutes
Tailwind =3.14 minutes
Headwind=16.02 minutes
I cant tell the wind direction relative to your actual flight but hope this helps you.
I'm guessing you ran out of battery. I don't fly when the wind is 18MPH.
Thank you for the calculations I have no luck finding my phantom so far I plan on upgrading to the phantom 4 so I can use my controller . I will be still searching for this one and still trying to get to a pc with my iPad, work has been very busy. Thank you all !
Tim Dawes what do you mean by assuming 1/3 of the fight in each wind condition ? I appreciate this I’m just trying to understand so I can put this to use in my search. How about this. Assuming the flight out is completely in the tailwind and the flight back is completely in headwind. How far back do you think it would make it until critical battery autoland ? And since there was a loss of signal for the entire return trip I’m assuming “smart RTH” was not activated ?
It was flying under Litchi, so no RTH due to disconnect. It could still abort the mission due under smart battery protocol, but it won't fully have taken the wind into account. I think the reference to 1/3 of the flight in each condition was because he didn't know the wind direction relative to the flight.
Sar104
28.8 minutes time to fly out with tail wind and back against headwind.
Time to fly 13,941' @ 33.6 MPH (with tail wind) is 4.8 minutes
Time to fly 13,941' @ 6.6 MPH (against head wind) is 24 minutes.
This does not include time flown before starting the Litchi mission.
28.8 minutes time to fly out with tail wind and back against headwind.
Time to fly 13,941' @ 33.6 MPH (with tail wind) is 4.8 minutes
Time to fly 13,941' @ 6.6 MPH (against head wind) is 24 minutes.
This does not include time flown before starting the Litchi mission.
Yup. Pretty sure this is a case of simply running out of battery.
Well this was a tough lesson to learn but I know once I order my phantom 4 to be way more careful planning missions. When I launched this flight I had a bad feeling It was too far and too windy but I had too much confidence in my P3a she’s flew some incredible flights but should of got way more hours out of her. Live and learn right. Also thank you for the calculations I will continue to search for her but defiantly trying to find a good buy for My next phantom .
Ya. Sorry about this but it's encouraging to know that Litchi didn't let you down. It's a great app that I love using but want to be able to trust. Good luck with your P4 which by the way shouldn't be as susceptible to developing cracks around the motor mounts (a real plus !).
In a way I feel as though litchi kind of let me down. I will not stop using it that’s for sure. I guess I only say litchi let me down is because I lost my bird. I know it was pilot error trying to fly back against a headwind. And it’s a fact that litchi’s estimated time of mission does not account for wind. But it is what it is. Now is the p4 pro or advanced worth the extra money over a p4 standard ???
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