Mavic Air never returned
- Thread starter TodayDee72
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No - I meant did you look at the image? The flight path is clearly heading for the trees.
Yes.. the Google earth picture is very accurate.. I looked in those trees quite a bit. If it’s in the trees, it might save it from the snow damage. No risk of it being moved, it’s rural and private land.
That's not consistent with the log, which shows that the flight started at 430 seconds. That almost certainly means that you didn't change the battery immediately before that flight.
These are your stick inputs for the last minute of the flight - you were clearly trying to fly the aircraft rather than let it return to home.
Apparently … I must practice more and absolutely pay better attention to the control. Today I used my iPad instead of the iPhone. I like the larger screen but I must have been fighting the drone more than I could see. I lost the camera view just over the reservoir.. the flight you see to the right.. I had no visual.
Yesterday I kept having the Gimble Motor Overload error but this morning I recalibrated and the error cleared
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Sounds like it might be.
If they are the only trees about, then -3' from take off point, -20' at the location, = it COULD be ~ 15' - 17' off the ground level there.
Not sure if that's the reason sar104 came to that conclusion, but possible.
Just thinking out loud in offering > don't look just on the ground.
That could be a good thing with the snow.
The tree foliage might keep some of the falls off the drone.
At least not allow total coverage as much as on the ground.
Good luck.
Edit - lol, just saw page 2 posts, again, good luck.
spetersen
Well-Known Member
I hope you find it, but its stories like these that makes flying VLOS seem like a good idea.
If you were flying VLOS this wouldn't have been an issue since you would have seen it land. Just saying.
Its a good lesson to learn actually. I have flown a flight out just to see just how far the drone would go... lost signal... auto landed. I thought I had enough battery to return, but that wasn't the case. I retrieved my drone since it was flat land in the desert with no trees or obstacles. That taught me to follow the rules a bit tighter. Now, VLOS as best I can with these old eyes and/or a spotter that has better eyes.
If you were flying VLOS this wouldn't have been an issue since you would have seen it land. Just saying.
Its a good lesson to learn actually. I have flown a flight out just to see just how far the drone would go... lost signal... auto landed. I thought I had enough battery to return, but that wasn't the case. I retrieved my drone since it was flat land in the desert with no trees or obstacles. That taught me to follow the rules a bit tighter. Now, VLOS as best I can with these old eyes and/or a spotter that has better eyes.
@TodayDee72, were you not monitoring the battery level during the flight, or was the battery level incorrectly showing higher levels?
One other thing you might want to consider is your altitude above sea level. At nearly 7,000 ft msl, your drone's propellers are not as efficient as they would be at sea level. But in the cold of winter this would not be very significant. During the summer or hotter months, density altitude will definitely have an effect on your drone's performance and battery flight time. The drone's electric motors do not suffer this decrease in efficiency, only their propellers and their "bite" into the thinner air, which translates into faster spinning motors and the subsequent increase in battery discharge rates. I used to live in Colorado Springs which is about 6,000 feet msl and on a few of those hot summer days, density altitude was over 10,000 feet, and for my real aircraft with a non-turbo internal combustion engine, I would ground my flight. So to use your location near Pleasant View, CO for yesterday's barometric pressure, you stated that it was around the time of some snowfall. Storms are almost always associated with a low pressure system and today (2/22/22) your barometric pressure is around 30.1 inHg and rising. So my guess would be that you were probably around 28 inHg or 29 inHg barometric pressure during your flight yesterday. Given your altitude above sea level and pressure, your density altitude could have been as much as 1,000 feet or more above where you were standing which would put your drone close to 8,000 feet density altitude. To use the Density Altitude Chart, find your current Altimeter Setting in the first column. This is your barometric pressure used for your take off position. Then go directly to the right and add or subtract the value in that column. For example, my elevation above sea level is 6,910 and the barometric pressure is 28.7 inHg. I must add 1,148 feet to to 6,910 feet to get my density altitude of 8,058 feet. Just something to think about.
The first step is to find pressure altitude. To do this you will have to calculate it manually since you most likely don't have an aircraft altimeter handy! You can use a weather app on your phone or computer before you leave your house to calculate it manually:
1. Subtract the current altimeter setting from the standard pressure of 29.92 inHg.
2. Multiply by 1,000.
3. If you have a negative number, subtract it from the field elevation. If a positive number, add it to the field elevation.
Then to calculate the Density Altitude
1. Find the outside air temperature on the bottom temperature scale.
2. Draw a line straight up until you reach the diagonal line that corresponds to the current pressure altitude.
3. From that spot on the line, draw a line directly left and read the density altitude off the vertical scale.
Definitions:
True altitude
The drone's actual height above sea level.
Pressure altitude
The height above a standard datum plane. In reality, it’s simply a theoretical value used to calculate performance. Obtain it through either reading the altitude when you set 29.92 in the altimeter or by calculating it manually.
Density altitude
Pressure altitude corrected for nonstandard temperature. This is the altitude the drone actually “feels.”
Absolute altitude
The drone's height above the ground. Also known as agl, or above ground level.
Indicated altitude
Simply the altitude read off the face of an altimeter of an aircraft. (consumer drones don't have altimeters)
APPLE IPHONE WEATHER APP (iOS 15.4):
The first step is to find pressure altitude. To do this you will have to calculate it manually since you most likely don't have an aircraft altimeter handy! You can use a weather app on your phone or computer before you leave your house to calculate it manually:
1. Subtract the current altimeter setting from the standard pressure of 29.92 inHg.
2. Multiply by 1,000.
3. If you have a negative number, subtract it from the field elevation. If a positive number, add it to the field elevation.
Then to calculate the Density Altitude
1. Find the outside air temperature on the bottom temperature scale.
2. Draw a line straight up until you reach the diagonal line that corresponds to the current pressure altitude.
3. From that spot on the line, draw a line directly left and read the density altitude off the vertical scale.
Definitions:
True altitude
The drone's actual height above sea level.
Pressure altitude
The height above a standard datum plane. In reality, it’s simply a theoretical value used to calculate performance. Obtain it through either reading the altitude when you set 29.92 in the altimeter or by calculating it manually.
Density altitude
Pressure altitude corrected for nonstandard temperature. This is the altitude the drone actually “feels.”
Absolute altitude
The drone's height above the ground. Also known as agl, or above ground level.
Indicated altitude
Simply the altitude read off the face of an altimeter of an aircraft. (consumer drones don't have altimeters)
APPLE IPHONE WEATHER APP (iOS 15.4):
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March411
Well-Known Member
360 Guy
Well-Known Member
Flyist
Member
Wind can blow the drone off its true GPS coordinates so the internal compass thinks it's somewhere else. That happened to me with the drone going into ATTI mode about 2000 feet out. Then it came out of ATTI but I still almost lost it as it kept thinking it was somewhere else. I finally landed it by me safely. When I looked at the flight data, the thing thought it had landed 3000 feet away from me. Since then if wind is blowing I keep it in VLOS and never far away.
That's rather confused.
Wind can blow the drone (if the wind is strong enough).
The compass only gives directional data, it don't know where the drone is at all.
It's hard to make sense of that.
The drone's GPS tells the drone where it actually is.
It's not going to keep thinking it was somewhere else or think it's 3000 ft away from you when it's not.
If you post your flight data, that will help find out what actually happened in your incident.
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That's all very interesting but not relevant to the OP's incident.
The Mavic Air is good for takeoff up to 16000 ft and the incident was entirely due to flying too long/too far with a battery that was already more than half used before this flight.
We were not able to find the drone. Searched easy 4 more hours in the area with multiple searchers. The wind was definitely a player, as was the storm, and my novice flying. I am very sure that something went wrong and it was a flyaway. Trees were searched in great detail. I will definitely be more careful with my Air2s than this drone. I don't think I will ever know what really happened. I did upload the fly records and the experienced pilot said that my battery though starting the flight with 44% was not it's first flight after charging. Though it was. Not sure if the charger didn't reflect right but there were several pieces to this puzzle I don't know if I will ever know. Maybe someday the drone will be found and I can watch the footage on the SD card as I was recording. It is not going to be found by another person because it is a very rural, isolated piece of property. If I ever do find it - I sure hope the recordings help tell a story. Thank you for that great info Strega315!!! That really helps understand, especially knowing I will be flying at 13,000 feet!
I'm sorry to disagree, and apologies if this sounds harsh, but nothing went wrong other than your flying and decision making. This event is fully explained by the log file, as has already been pointed out. This was not a flyaway - you flew it away.
The flight record starts at 430 seconds and 44% battery, which unambiguously means that you had flown, landed and then took off again with that same partially charged battery without even powering off the aircraft, let alone changing the battery. Note also that the battery temperature at takeoff was 44°C - further proof that this was not a fresh battery.
You then obviously didn't check the battery reading on screen, flew it directly downwind in a 20 mph wind which would have been a problem even with a fully charged battery, and then continued to ignore the battery level indications and other warnings. When it finally entered RTH, and later autoland, you flew it off course with various unnecessary stick inputs that prevented a controlled landing and clear location record.
