When reading the Mavic Airs manual it said it would trigger a Failsafe RTH 'retracing its path', but that left a few questions open (at least with me).

Glad to say that there is a revised manual that was releases on the 5th of March, although the revision number hasn't changed, it now fully describes the Failsafe RTH's procedure.
Here's a screenshot:


Good to know that the retracing will be done for 60 seconds, and if connection is not reastablished within those 60 seconds, the craft will go straight to home.

One word of note, be mindfull for locations that could be viable for signal dropout, If youre flying under a tree or brigde and you lose signal, its original path retracing will be performed at the RTH altitude you set in the DJI Go app.

You've pointed out a couple of things that are good to know. 1) that there is a recent update to the manual and 2) I always had questioned how the Fail Safe RTH would work.  The original manual suggested that it would retrace it's entire previous path home, which seemed to me to very problematic.  Knowing it will fly directly home after 60 seconds (if signal is still lost) is a relief.  Thanks for the post

Thank you for the very valuable information!

Tomsbird Posted at 2018-3-11 08:59
You've pointed out a couple of things that are good to know. 1) that there is a recent update to the manual and 2) I always had questioned how the Fail Safe RTH would work.  The original manual suggested that it would retrace it's entire previous path home, which seemed to me to very problematic.  Knowing it will fly directly home after 60 seconds (if signal is still lost) is a relief.  Thanks for the post

You're welcome, I've had the exact same questionmarks like you did, so I thought I'd share when the new manual popped up.

Didn't know that the manual was updated.
Thank You

Thanks for showing that.
Had not read it so far.

Thanks for your attention. Please be careful to fly your drone and read the manual carefully.

This post needs to be read by every MA user.

I think someone should test this. There is absolutely no point in 'retracing the flight path' at a different altitude?? It may as well do a 'normal' RTH, go to its RTH height and come home?
If it were to try to come back the way it went in, ie height and direction, that could be handy I'spose??

Does the retrace its entire previous home path only apply to the Air or both Mavics? Is the Spark also in the conversation?

Simmo1 Posted at 2018-3-18 20:10
I think someone should test this. There is absolutely no point in 'retracing the flight path' at a different altitude?? It may as well do a 'normal' RTH, go to its RTH height and come home?
If it were to try to come back the way it went in, ie height and direction, that could be handy I'spose??

There was a topic I can't find it anymore. which confirmed the craft went to RTH height first before retracing its path. The manual also seems to confirm this procedure.

I agree that going to RTH height first (when flying at lower altitide) would not always be desired.

On the other hand, ascending to higher altitude could be the best way to move out of the interference and regain connection.   

davidmartingraf Posted at 2018-3-18 21:07
Does the retrace its entire previous home path only apply to the Air or both Mavics? Is the Spark also in the conversation?

At this point and time, just for the Mavic Air. It inherited the procedure from the Phantom.

Hey LosBol, Buddy I'm not disagreeing with you Sir, simply saying it needs testing!
If you retrace a path, at a different altitude, then that is a nightmare.
YES! RTH and go high above all crap you can hit and come straight home!
No wasting battery trying to follow a route, to find no connection, and go to RTH altitude...then come home....stupid in my book...

Simmo1 Posted at 2018-3-19 02:14
Hey LosBol, Buddy I'm not disagreeing with you Sir, simply saying it needs testing!
If you retrace a path, at a different altitude, then that is a nightmare.
YES! RTH and go high above all crap you can hit and come straight home!

I'm not arguing you Simmo1, you have a very good and valid point.

LoSBoL Posted at 2018-3-19 02:08
At this point and time, just for the Mavic Air. It inherited the procedure from the Phantom.

Oh that's not fair and why wouldn't such feature be easily available with Mavic Pro using Ocusync? I would venture to guess retracing your previous path is harder for WiFi, at the point of disconnect the drone needs to travel in a straight line pointing to RTH so that re-connection quickly is reestablished? Ocusync and Lightbridge can handle this feature not only because it's not WiFi, but because these drones have higher battery run times, and tracing your previous path takes the drone longer to RTH. The Mavic Air has 21 minutes of battery run time, compared to 27 minutes for the Phantom and Mavic Pro? As a result, I would be very weary of having this feature incorporated in my Mavic Air. The incorporation of this feature to the Mavic Pro seems like common sense for DJI, I wonder why they are seemingly neglecting this enhancement and other proven ones for the Mavic Pro?

I sense we are close to DJI releasing the Mavic Pro 2 very soon, which would make sense why they're holding back on introducing additional enhancements to the original Mavic Pro?

Yep, I have this feature on my Phantom 4 Pro - it’s called flight autonomy. The drone creates 3D images of the environment and records landmarks in its memory to fly towards when signal is lost. It does not immediately ascend in altitude whilst retracing it’s route - if the signal is not regained after a minute then it initiates failsafe RTH as normal and ascends at that point. The main purpose of flight autonomy is so you don’t lose the shoot you were doing due to signal loss and can regain position quicker knowing to change your flight route to prevent losing signal again. Note that low battery and smart RTH do not engage flight autonomy and will fly straight back at the preset RTH altitude (unless flying higher anyway when engaged).

davidmartingraf Posted at 2018-3-19 08:04
Oh that's not fair and why wouldn't such feature be easily available with Mavic Pro using Ocusync? I would venture to guess retracing your previous path is harder for WiFi, at the point of disconnect the drone needs to travel in a straight line pointing to RTH so that re-connection quickly is reestablished? Ocusync and Lightbridge can handle this feature not only because it's not WiFi, but because these drones have higher battery run times, and tracing your previous path takes the drone longer to RTH. The Mavic Air has 21 minutes of battery run time, compared to 27 minutes for the Phantom and Mavic Pro? As a result, I would be very weary of having this feature incorporated in my Mavic Air. The incorporation of this feature to the Mavic Pro seems like common sense for DJI, I wonder why they are seemingly neglecting this enhancement and other proven ones for the Mavic Pro?

I sense we are close to DJI releasing the Mavic Pro 2 very soon, which would make sense why they're holding back on introducing additional enhancements to the original Mavic Pro?

Don't shoot the messenger

But yeah, the Mavic Pro is antique   (just kidding folks)

A CW Posted at 2018-3-19 08:54
Yep, I have this feature on my Phantom 4 Pro - it’s called flight autonomy. The drone creates 3D images of the environment and records landmarks in its memory to fly towards when signal is lost. It does not immediately ascend in altitude whilst retracing it’s route - if the signal is not regained after a minute then it initiates failsafe RTH as normal and ascends at that point. The main purpose of flight autonomy is so you don’t lose the shoot you were doing due to signal loss and can regain position quicker knowing to change your flight route to prevent losing signal again. Note that low battery and smart RTH do not engage flight autonomy and will fly straight back at the preset RTH altitude (unless flying higher anyway when engaged).

Hmmm, so the Phantom doesn't raise to RTH altitude when the connection is lost.

Weird, It begs the question why DJI would have changed the procedure for the Air?

Are you sure it does?

A CW Posted at 2018-3-19 10:26
Are you sure it does?

Pretty sure, it was concluded in a 'flyaway' topic I can't find anymore, (to many topics of those...)

I’m guessing that would be from flight records - will be interesting to see them

A CW Posted at 2018-3-19 10:45
I’m guessing that would be from flight records - will be interesting to see them

Indeed, the wonderfull search option from this site isn't doing me any miracles yet ;)

LoSBoL Posted at 2018-3-19 09:32
Hmmm, so the Phantom doesn't raise to RTH altitude when the connection is lost.

Weird, It begs the question why DJI would have changed the procedure for the Air?

They didn’t, when air loses radio signal after 3 seconds it will retrace it’s route home at its present height if it resumes signal it will stop and hover and wait for 10 seconds the pilot can cancel RTH if he doesn’t within 10 seconds MavAir will proceed to RTH.

So it’s the very same as P4Pro. They both have same system that maps out out going flight and can fly same route home so no danger of obstacles. It’s another great redundancy that this tiny aircraft possesses.

hallmark007 Posted at 2018-3-19 11:05
They didn’t, when air loses radio signal after 3 seconds it will retrace it’s route home at its present height if it resumes signal it will stop and hover and wait for 10 seconds the pilot can cancel RTH if he doesn’t within 10 seconds MavAir will proceed to RTH.

So it’s the very same as P4Pro. They both have same system that maps out out going flight and can fly same route home so no danger of obstacles. It’s another great redundancy that this tiny aircraft possesses.

Good to know mate - it didn't make sense just shooting up to retrace the route.

hallmark007 Posted at 2018-3-19 11:05
They didn’t, when air loses radio signal after 3 seconds it will retrace it’s route home at its present height if it resumes signal it will stop and hover and wait for 10 seconds the pilot can cancel RTH if he doesn’t within 10 seconds MavAir will proceed to RTH.

So it’s the very same as P4Pro. They both have same system that maps out out going flight and can fly same route home so no danger of obstacles. It’s another great redundancy that this tiny aircraft possesses.

I'm pretty sure there was a topic which discussed this and there were aircraft flightrecordings showing this for the Mavic Air. The gain in altitude was even debated there if it was preferable or not.

A CW Posted at 2018-3-19 11:08
Good to know mate - it didn't make sense just shooting up to retrace the route.

In fairness I have never had to use it, but it’s nice to know if you fly around a building that it won’t try and climb above that building and then fly into another higher building.

I couldn't find that particulair topic, but this topic does answer the question

https://forum.dji.com/thread-136983-1-1.html

hallmark007 Posted at 2018-3-19 11:17
In fairness I have never had to use it, but it’s nice to know if you fly around a building that it won’t try and climb above that building and then fly into another higher building.

Nice to know it's there but agreed, always best to never have to use it in the first place.

LoSBoL Posted at 2018-3-19 11:20
I couldn't find that particulair topic, but this topic does answer the question

https://forum.dji.com/thread-136983-1-1.html

It’s an exceptionally safe option but will not preform same in low battery return home as when that happens it need to get home as fast as it can . The technology is amazing.

LoSBoL Posted at 2018-3-19 09:30
Don't shoot the messenger

But yeah, the Mavic Pro is atique   (just kidding folks)

No that's perfectly fair but things eventually change.

Yes, they do ;)

hallmark007 Posted at 2018-3-19 11:30
It’s an exceptionally safe option but will not preform same in low battery return home as when that happens it need to get home as fast as it can . The technology is amazing.

Maybe the Phantom also ascends to RTH height before retracing its path? The video in that topic shows the Mavic Air does, Now I'm wandering if the procedures are different?
You can however debate if ascending to RTH is the safest option.

As for a low battery return to home, I guess that that would probably overrule failsafe return to home.

LoSBoL Posted at 2018-3-19 12:01
Maybe the Phantom also ascends to RTH height before retracing its path? The video in that topic shows the Mavic Air does, Now I'm wandering if the procedures are different?
You can however debate if ascending to RTH is the safest option.

Phantom doesn’t ascend but the big difference with P4Pro is it has a much bigger battery, also the likelihood of not regaining radio control are very minute so the whole process for both craft is an exceptional redundancy first seen in P4Pro and inspire and I’m sure we will see this being the normal for new dji aircraft.

davidmartingraf Posted at 2018-3-19 08:04
Oh that's not fair and why wouldn't such feature be easily available with Mavic Pro using Ocusync? I would venture to guess retracing your previous path is harder for WiFi, at the point of disconnect the drone needs to travel in a straight line pointing to RTH so that re-connection quickly is reestablished? Ocusync and Lightbridge can handle this feature not only because it's not WiFi, but because these drones have higher battery run times, and tracing your previous path takes the drone longer to RTH. The Mavic Air has 21 minutes of battery run time, compared to 27 minutes for the Phantom and Mavic Pro? As a result, I would be very weary of having this feature incorporated in my Mavic Air. The incorporation of this feature to the Mavic Pro seems like common sense for DJI, I wonder why they are seemingly neglecting this enhancement and other proven ones for the Mavic Pro?

I sense we are close to DJI releasing the Mavic Pro 2 very soon, which would make sense why they're holding back on introducing additional enhancements to the original Mavic Pro?

It was first introduced to P4Pro and inspire both these aircraft were released in December 2016 three months after release of MP so I’m presuming you won’t see it in MP not now but will almost certainly be in MP2 when ever we see it, that’s just the way technology is, the difference in price of Mavic combo and MavAir combo is only €100 and IMO that is about right.

hallmark007 Posted at 2018-3-19 12:44
It was first introduced to P4Pro and inspire both these aircraft were released in December 2016 three months after release of MP so I’m presuming you won’t see it in MP not now but will almost certainly be in MP2 when ever we see it, that’s just the way technology is, the difference in price of Mavic combo and MavAir combo is only €100 and IMO that is about right.

I think I'd rather take Ocusync, Follow Me, and Cinema 4K 4096x2160p of the Mavic Pro than APAS, Rear OA, and RTH previous path of the Mavic Air.

I view the Mavic Air and Spark in the same class since both are WiFi, yet I'd rather have hand launch and landing of the Spark than hand take-off and landing of the Mavic Air.

To me, owning both the Mavic Pro and Spark you get the best of both worlds. The Mavic Air is a jack of all trades and master of none.

davidmartingraf Posted at 2018-3-19 14:17
I think I'd rather take Ocusync, Follow Me, and Cinema 4K 4096x2160p of the Mavic Pro than APAS, Rear OA, and RTH previous path of the Mavic Air.

I view the Mavic Air and Spark in the same class since both are WiFi, yet I'd rather have hand launch and landing of the Spark than hand take-off and landing of the Mavic Air.

Mavic Air is nothing like spark and I have both Spark is a great craft but totally different than MavAir, so to is Mavic Pro , follow me is littered with problems on Mavic Pro and needs serious updates before it works properly.
Mavic Pro is a great flying drone seriously lacks speed in RTH mode and many have lost it because of this problem, I believe it will be sorted in Mavic2  , these craft are evolving very fast its becoming hard to keep up with everything.

hallmark007 Posted at 2018-3-19 14:57
Mavic Air is nothing like spark and I have both Spark is a great craft but totally different than MavAir, so to is Mavic Pro , follow me is littered with problems on Mavic Pro and needs serious updates before it works properly.
Mavic Pro is a great flying drone seriously lacks speed in RTH mode and many have lost it because of this problem, I believe it will be sorted in Mavic2  , these craft are evolving very fast its becoming hard to keep up with everything.

I have flown with the Spark RTH full pitch forward that increases its speed from ~22 to ~30 miles per hour, although I haven't had the chance to fully test the full pitch forward in RTH with Mavic Pro. Are you saying the RTH speed on Mavic Pro cannot be adjusted upward in full pitch forward like on the Spark and Mavic Air? Thanks for your feedback!

davidmartingraf Posted at 2018-3-19 08:04
Oh that's not fair and why wouldn't such feature be easily available with Mavic Pro using Ocusync? I would venture to guess retracing your previous path is harder for WiFi, at the point of disconnect the drone needs to travel in a straight line pointing to RTH so that re-connection quickly is reestablished? Ocusync and Lightbridge can handle this feature not only because it's not WiFi, but because these drones have higher battery run times, and tracing your previous path takes the drone longer to RTH. The Mavic Air has 21 minutes of battery run time, compared to 27 minutes for the Phantom and Mavic Pro? As a result, I would be very weary of having this feature incorporated in my Mavic Air. The incorporation of this feature to the Mavic Pro seems like common sense for DJI, I wonder why they are seemingly neglecting this enhancement and other proven ones for the Mavic Pro?

I sense we are close to DJI releasing the Mavic Pro 2 very soon, which would make sense why they're holding back on introducing additional enhancements to the original Mavic Pro?

Reading the description, it seems that it may be using the bottoms sensors to trace the path more accurately. When i saw the other post about this, I assumed it did not, but now I think I was wrong. The Pro looks like it has bottom sensors that should be capable of this, but they are oriented different. Perhaps it's just going to take a bit more time to add this to the Pro due to the different sensor positioning. The Spark only has infrared sensors so I would never expect this to be supported on the Spark. The RTH does seem a bit counter productive to me too. This behavior should be a selectable option.

davidmartingraf Posted at 2018-3-19 14:17
I think I'd rather take Ocusync, Follow Me, and Cinema 4K 4096x2160p of the Mavic Pro than APAS, Rear OA, and RTH previous path of the Mavic Air.

I view the Mavic Air and Spark in the same class since both are WiFi, yet I'd rather have hand launch and landing of the Spark than hand take-off and landing of the Mavic Air.

Thank you for sharing your opinion on which craft you prefer... The Mavic Air folds, therefore it belongs in the Mavic class. Either way it doesn't matter which craft you or I prefer, or in which class one may think it belongs, there are a quite a few topics comparing the crafts, but I fail to see the relevance of posting such opinions in a topic about failsafe RTH procedures.

hallmark007 Posted at 2018-3-19 14:57
Mavic Air is nothing like spark and I have both Spark is a great craft but totally different than MavAir, so to is Mavic Pro , follow me is littered with problems on Mavic Pro and needs serious updates before it works properly.
Mavic Pro is a great flying drone seriously lacks speed in RTH mode and many have lost it because of this problem, I believe it will be sorted in Mavic2  , these craft are evolving very fast its becoming hard to keep up with everything.

As one of the first evolving tech I would like to see top sensors, Even though we are strongly advised not to fly beneath trees or underneath anything, I can't get my head around crafts activating fully automated procedures while not being able to assess if its safe to do so.