M2P vs MP1 Disconnect/RTH

[charliesRig]

Diffrents :
as I was flying my M2P
I had a very rare “Loss of Signal”RTH
At first watching Mavic
hover then start to fly away stop and revers then headed
To home port
This took about 3 minutes


I recall someone calling out this exact maneuver in a post here

MP1 when
“Loss of signal “RTH
would stop hover for around 30 sec to 1 minutes and move on to Home port

Why bring this up
Myself being a new M2P pilot.

I have been reading lately a lot of
Disconnect/Loss of signal M2P
Post
And what I have learned is....
When you get loss of signal(M2P)
Don’t stress out before you react
( Give it a long moment)
Your new Mavic is a smart bird
And what you are watching when it looks like it’s flying away
Is your M2P retracing it steps looking to reconnect if it does not
It will RTH

Again in one word the Mavic2 Pro
.........Amazing.!

......(and yes I’m still on fire).....cR

... and would like to add Never fly with less then 20%
....and alway inspect your battery is
properly seated in your Mavic

 

[old man mavic]

apparently it retraces the last 60 seconds of it flight to try and regain connection, then if that fails, it will come back home, because of this it is important to make sure your RTH height is high enough to clear any obstacles that it could encounter

 

[Thomas B]

Also, be aware that the battery power life decreases will begin to occur faster and accelerate the decline as the battery charge gets below 30%. Be sure you have time to get home and don’t end up fighting a forced landing in a place you don’t want it to land.

 

[gnirtS]

The manual states quite clearly what the LOS RTH behaviour is. Im kind of concerned a new owner hasnt read it.

 

[old man mavic]

The manual states quite clearly what the LOS RTH behaviour is. Im kind of concerned a new owner hasnt read it.

Charles is a long time flier i think he was just trying to point out that there is a difference in the way the original mavic and the mavic 2 reacts when a RTH happens

 

[gnirtS]

"and what i learned" doesnt make it sound that way...

 

[Paul2660]

Glad to see it worked as it should. Tech of the M2 Pro for that matter all DJI drones still amazes me.

Paul C

 

[charliesRig]

"and what i learned" doesnt make it sound that way...

In my defense :
I’m old
......and forgotten more then I learned.!
I have read the manual’s.
but you can’t really appreciate something until you actually experience it in real life
It said it on “paper” does not mean you take it as end all to be all .!

just want to Share my experience make a post
For us new M2P pilot’s
After reading 2 or 3 post about Disconnecting M2P

“Don’t panic if you Loss connection and the bird looks like it’s flying away”

(For me it was a “Ah-ha moment)

After flying/crashing the Mavic Pro for 2.5 yrs The M2P is a worthy up grade
To my unstable (software glitchy) MP1
IMO

(And yes I’m still on fire)
..... cR

 

[Thomas B]

In my defense :
I’m old
......and forgotten more then I learned.!
I have read the manual’s.
but you can’t really appreciate something until you actually experience it in real life
It said it on “paper” does not mean you take it as end all to be all .!

just want to Share my experience make a post
For us new M2P pilot’s
After reading 2 or 3 post about Disconnecting M2P

“Don’t panic if you Loss connection and the bird looks like it’s flying away”

(For me it was a “Ah-ha moment)

After flying/crashing the Mavic Pro for 2.5 yrs The M2P is a worthy up grade
To my unstable (software glitchy) MP1
IMO

(And yes I’m still on fire)
..... cR

Agree! I can read about it... but until I do it or see it occur with my drone it just doesn’t give me that serendipity.

 

[offtheback]

Glad to see it worked as it should. Tech of the M2 Pro for that matter all DJI drones still amazes me.

Paul C

I agree that that the tech is amazing.When a stranger asks about the drone+I talk about precision RTH,obstacle avoidance etc I am almost as amazed as they are.

 

[GadgetGuy]

Also, be aware that the battery power life decreases will begin to occur faster and accelerate the decline as the battery charge gets below 30%. Be sure you have time to get home and don’t end up fighting a forced landing in a place you don’t want it to land.

While you are correct about the nonlinear decline of the battery charge, it does not take place until you reach 0%, instead of 30%. From 100% to 0%, based upon my experience with over 200 flights on the M2, the battery decline is linear until you reach 0%, not 30%. If you have anything to support the 30% figure, I would love to see it! Also, once you reach 0%, you can still fight the Autoland until one of the cells drops below 3.0V, which still gives you another 2 additional minutes of flight. So, if you are still over water trying to make it to dry land, fear not, there is still plenty of gas left in the tank, if you know how to use it, to recover your aircraft. It may destroy the future usability of the battery going below 0%, but it can save your aircraft! Once the lowest cell on the battery drops below 3.0V, you can no longer fight the descent, and it will start descending, but it will still fly forward, so make sure you have plenty of altitude to counter the descent while you continue forward flight to reach dry land!

 

[Thomas B]

While you are correct about the nonlinear decline of the battery charge, it does not take place until you reach 0%, instead of 30%. From 100% to 0%, based upon my experience with over 200 flights on the M2, the battery decline is linear until you reach 0%, not 30%. If you have anything to support the 30% figure, I would love to see it! Also, once you reach 0%, you can still fight the Autoland until one of the cells drops below 3.0V, which still gives you another 2 additional minutes of flight. So, if you are still over water trying to make it to dry land, fear not, there is still plenty of gas left in the tank, if you know how to use it, to recover your aircraft. It may destroy the future usability of the battery going below 0%, but it can save your aircraft! Once the lowest cell on the battery drops below 3.0V, you can no longer fight the descent, and it will start descending, but it will still fly forward, so make sure you have plenty of altitude to counter the descent while you continue forward flight to reach dry land!

Based on experience with over 200 M2P flights myself, and noticed primarily when hovering for hyperlapse, I do see the accelerated decline in battery time. So it appears experience may vary.

Can’t comment on time figures as I honestly have never landed with < 4% battery.

I think both of our points boil down to not routinely flying until battery life is very low.

 

[old man mavic]

why would you push the the batteries limits routinely, just because they can in perfect conditions keep the Mav airborn for some 30 mins we all know that in real world flying those times are not realistic i have mine set at first low warning at 40% and then critical at 25% i have 5 batteries and usually get around an 18-20 minute flight time per battery at 40% with over 250 flights they are still perfectly ok i keep an eye on them when not in use and only recharge them when i know i am going flying within 24 hours

 

[gnirtS]

The mavics do use more power hovering than moving. M1 was the same. The DJI endurance figures are quoted at a moving speed not a hover.
But yes, a 15 minute hyperlapse whilst flying v hovering is quite a noticeable difference in battery even if the movement is very slow.

 

[GadgetGuy]

Based on experience with over 200 M2P flights myself, and noticed primarily when hovering for hyperlapse, I do see the accelerated decline in battery time. So it appears experience may vary.

Can’t comment on time figures as I honestly have never landed with < 4% battery.

I think both of our points boil down to not routinely flying until battery life is very low.

Indeed! Different flying styles. My flights are all at 30mph, rather than in a hover (which is less efficient), and I can accurately predict the remaining flight time based upon percentage remaining, which is why, when it suddenly became very nonlinear below 0% that I miscalculated, and assumed I had enough battery to make it back, instead of trying to ditch land it safely and retrieving it.

Actually, my point is that there is plenty of battery left on the M2, even after 10%, and DJI's Autoland is very conservative. Based upon previous algorithms, where 0% meant 3.0V per cell on the P3P, at today's 0% on the M2, the battery voltage is still 3.5V per cell under full load while flying, which is nowhere near damaging to the battery. It declines rapidly after that, so don't do it, but landing under 10% is not a problem, but if truth be told, I would always prefer to land with at least 4%, too!

 

[GadgetGuy]

why would you push the the batteries limits routinely, just because they can in perfect conditions keep the Mav airborn for some 30 mins we all know that in real world flying those times are not realistic i have mine set at first low warning at 40% and then critical at 25% i have 5 batteries and usually get around an 18-20 minute flight time per battery at 40% with over 250 flights they are still perfectly ok i keep an eye on them when not in use and only recharge them when i know i am going flying within 24 hours

Nobody is getting 30 minute flight times even to 0% in real life conditions. I get 23-25 minutes, handcatching between 5-9% remaining battery on average.

Below is how DJI calculated their M2 flying times.
Overall flight time at 15mph, and no wind, even by DJI's calculations to 15% remaining is only 25 minutes. I fly in 10mph wind at 30mph and get 23 minutes to 5% remaining.

 

[DanMan32]

Zero is 3.5v? No wonder I feel like i have less time below 30% than I did on my P3.

 

[GadgetGuy]

Zero is 3.5v? No wonder I feel like i have less time below 30% than I did on my P3.

Indeed! Here is a recent GO 4 screenshot of 5% remaining battery, still showing 3.66V on the lowest cell. 0% is actually closer to 3.55V per cell than 3.50V. You still have full aircraft control (although forward speed is slowed to roughly 22mph), and can even continue to ascend until the lowest cell reaches 3.0V, which is at a full 2 minutes of flight time after reaching 0% remaining battery! Even then, it does not crash, or shut off. It only starts an uncancellable descent, while still giving stick control in every other direction. Since the uncancellable descent can be set in flight parameters to as low as 2.5V, if you have enough altitude when the descent becomes uncancellable, you can probably fly another 15 to 30 seconds after reaching 3.0V to make it back over water!

 

[HawkEye76]

I had a battery that gave up at 15% when one cell collapsed. Looking back at the logs on airdata I could se that there was indeed warning signs in the cell deviation. However I do not check every log in detail. Only warning in the app was 3 sec before it shut of. I was at 0.4m altitude on my way to land on grass so no real crash. For this reason I like to play safe and land between 20 and 30%.

 

[GadgetGuy]

I had a battery that gave up at 15% when one cell collapsed. Looking back at the logs on airdata I could se that there was indeed warning signs in the cell deviation. However I do not check every log in detail. Only warning in the app was 3 sec before it shut of. I was at 0.4m altitude on my way to land on grass so no real crash. For this reason I like to play safe and land between 20 and 30%.

I doubt the 15% caused the cell collapse. Cell collapse can potentially happen at any time, which is why displaying the lowest cell voltage next to the battery percentage is highly recommended in GO 4, like above. I had a P3P battery shutoff when the app reported 87% remaining within 15 seconds of takeoff. It dropped from 200 feet straight down, 10 feet away from me, as I had ascended straight up. Dodged a bullet!