RTH - Tips for new Pilots.

[Kevjones777]

Hi pilots. I cannot emphasise how important it is to understand how the RTH feature works and why it is so important to actually set it. I have heard all the "Top Guns" say they never use it and it is a gimmic feature. Well unfortunately it is not as it is embedded in the software and cant be turned off.

The Home point setting has two options which is important to know if you trigger a return to home on a low battery for example.
1. Return to the exact spot the aircraft took off from - this is very very accurate and the aircraft will literally land within inches of where it took off from. and Return to the controller - This is more complex and the issues with this will be discussed below.

If you set your return to home point where the aircraft is taking off from, namely, it's GPS position on the ground, this setting MUST be done each and every time prior to take off, dont assume that the aircraft has set this. It cannot set this location without strong GPS signals. It will TELL you that RTH has been set where the aircraft is standing and request that you check in on your map.. I cant look inside the code to see if the previous location has been erased or not when you power the aircraft on again following a previous flight. I strongly recommend that you ensure that this is set before you take off. Why ?

1. Due to the nature of RTH being integrated in the operation of the aircraft should you experience any technical difficulties with other aspects of the aircraft with a correctly set RTH you have a very good chance of recovering your aircraft. For example you are out of visual range and the camera stops working or the connection is lost.Or the battery develops a malfunction. At least the aircraft knows where it must return to.

Home Point setting to controller. In order for the aircraft to know where the controller is, it needs to have updated positional information being fed to it. This implies that this position is being transmitted to the aircraft. What you need to be careful of here is say you have this setting set and you drive off or walk off following the aircraft and for some reason you lose connectivity you are not going to be sure exactly what the last updated position of the controller was. I am sure you can deduce the results if for instance you were on a boat and assume the controller setting has been updated.

The home point settings work in conjunction with the RC signal lost and battery low warning however a malfunction of one of those readings can trigger this code as well. I would only use the hover function if I can see the aircraft at all times such as indoors.

Within each one of these settings there are various parameters that you need to set. For instance the RTH altitude. Make sure you choose an altitude that is higher than the tallest obstacle around you. When RTH is initiated. The default is battery at 30%. Initially I would leave this as it gives you enough time to exit RTH should you wish.

Once RTH is initiated you have the option of cancelling it. I strongly advise that you only do this once the aircraft is "under control" namely, you can see it, you have connectivity, the video feed is working.

Hopefully the new pilots will get something from this post. Safe flying.

 

[Lake_Flyer]

I have heard all the "Top Guns" say they never use it and it is a gimmic feature

That the 'top guns' don't use it is only because they never wait for it to kick in, as should every pilot, including, especially, newbies. RTH is a failsafe, not a flight mode one should use every time.
indeed, part of the checklist is always to check and set the RTH settings, just in case you do lose control (which you don't because you're well prepared and have mitigated the risks).

I never use it. Only occasionally testing that it actually works like I expect it to work.

 

[Kevjones777]

That the 'top guns' don't use it is only because they never wait for it to kick in, as should every pilot, including, especially, newbies. RTH is a failsafe, not a flight mode one should use every time.
indeed, part of the checklist is always to check and set the RTH settings, just in case you do lose control (which you don't because you're well prepared and have mitigated the risks).

I never use it. Only occasionally testing that it actually works like I expect it to work.

Yip I agree with your statement. The problem only arises when you need it and it's not set properly. I must admit the first time flying the MA was a bit daunting and I dont even recall watching the tablet. Had my eyes on the Aircraft the entire time. There is one hell of a lot of information to process when you starting out, on the screen. Even under perfect conditions there are all sorts of messages popping up to distract the new pilot. The post was not for us "Top Guns" ha ha ha.

 

[msinger]

Just to clarify a bit...

You have three options when the battery low message and conditions initiates a RTH

When the aircraft determines it only has enough battery to make it back to the home point, it'll display a message in DJI GO alerting the pilot that RTH will be auto initiated if not cancelled within 10 seconds. That feature is what DJI commonly calls "Smart Return-to-Home".

Return to the exact spot the aircraft took off from - this is very very accurate and the aircraft will literally land within inches of where it took off from

Each time the aircraft is started, it will always default to return to the last marked home point. After the aircraft starts up and first establishes a good GPS connection, it'll auto mark the home point. That's the location the aircraft will return to if the pilot does not manually reset the home point after it's initially marked.

Return to the controller - This is more complex and the issues with this will be discussed below

There is no option to return to the remote controller. If flying with a mobile device that contains a GPS receiver, the pilot can manually reset the home point to the mobile device's current location. After moving away from that new location, the pilot will need to manually reset the home point again (if desired).

The last option you can set is for the aircraft to hover where it stops

This is only an option for controlling what the aircraft does after the remote controller disconnects from the aircraft. By default, that setting is set to "Return-to-Home". It can be configured in the following section of DJI GO:

 

[Lake_Flyer]

Yip I agree with your statement. The problem only arises when you need it and it's not set properly. I must admit the first time flying the MA was a bit daunting and I dont even recall watching the tablet. Had my eyes on the Aircraft the entire time. There is one **** of a lot of information to process when you starting out, on the screen. Even under perfect conditions there are all sorts of messages popping up to distract the new pilot. The post was not for us "Top Guns" ha ha ha.

Totally agree Kev, in 'the old days' of fixed wing and heli flying, I didn't even have any telemetry. Only a timer (my watch). My first drones drones only had a tiny warning light, no FPV no RTH.
The amount of information on the screen, and the controller screen (MP), is way too much for most newbies to be able to keep their bird in sight. Glancing at the screen, trying to find a setting or reacting to a warning, you lose that little drone easily against the grey sky or a dark backdrop.

 

[Kevjones777]

Thanks for the clarification. You are correct in that the RTH - safe has two options, 1 being back to where it was set, and 2 back to the controller. Having just tried to set the home point to the controller I did notice how long it takes to establish that the GPS is strong enough to actually set it.

The point I am trying to make for "new" pilots is to get used to setting the RTH function and actually seeing that it was set.... it is because people assume that things are set that they crash. I know the aircraft sets the home point automatically if RTH was set up to bring the aircraft back to take off position. I am advising that you actually go and check it as part of your pre flight.

There is no hard and fast rule as to what pre flights you should do but just go and read how many pilots have taken off without a fixed GPS or tried setting home points at 50m altitude or pressed RTH by mistake. Waiting for the Home point set message is a good thing, but you dont have to do it. Thanks for the clarity much appreciated.

 

[msinger]

or tried setting home points at 50m altitude

What's wrong with that one?

 

[Kevjones777]

What's wrong with that one?

I meant setting it at 5o meters in the air up off the ground then pressing set. ha ha ha ha

 

[Kevjones777]

Just to clarify a bit...


When the aircraft determines it only has enough battery to make it back to the home point, it'll display a message in DJI GO alerting the pilot that RTH will be auto initiated if not cancelled within 10 seconds. That feature is what DJI commonly calls "Smart Return-to-Home".


Each time the aircraft is started, it will always default to return to the last marked home point. After the aircraft starts up and first establishes a good GPS connection, it'll auto mark the home point. That's the location the aircraft will return to if the pilot does not manually reset the home point after it's initially marked.


There is no option to return to the remote controller. If flying with a mobile device that contains a GPS receiver, the pilot can manually reset the home point to the mobile device's current location. After moving away from that new location, the pilot will need to manually reset the home point again (if desired).


This is only an option for controlling what the aircraft does after the remote controller disconnects from the aircraft. By default, that setting is set to "Return-to-Home". It can be configured in the following section of DJI GO:

View attachment 34779

@msinger I have updated it with your clarifications --- thanks.

 

[nikkolaa]

Last time I lower the first battery warning (set at 30%) DURING flight, when it popped in, in order to avoid having the alarm ringing constantly..

Bad idea, I almost ended up losing it with no battery, no smart RTH activated without any visual line of it (dark background at the time as o was flying below the starting point, on a cliff)..

It went fine cuz I've got the video feed, allowing to get back to the cliff, then lifting up to get it back on VLOS and quick landing..

I think I will keep flying with noisy alarm in case of, just not to think "hey, let's make a shot like this on my way back" when already in degraded mode..

 

[nikkolaa]

Ended up almost losing it, it's a big world sorry for "top guns"..

I could have found it easily afterwards, I guess, with last gps position if ended up landing by itself when battery running critically low

It's just something I haven't done (yet)

 

[Simmo]

. Waiting for the Home point set message is a good thing, but you dont have to do it. .

In my limited experience, this has accounted for many crashes.

 

[joot]

Good info...

 

[msinger]

I meant setting it at 5o meters in the air up off the ground then pressing set. ha ha ha ha

That would be an okay thing to do since marking the home point only updates the location (latitude & longitude) of the home point.

 

[Travisimo]

Thanks for posting tips regarding Return to Home. I agree that while it shouldn't be relied upon on as a regular part of flight, it certainly is an important safety feature. And you are right that it's essential to make sure your settings are correct and that the home point has been set properly. Here are a few additional comments regarding RTH:

• RTH can be initiated by the pilot by either touching the RTH icon in the app OR by pressing (and holding) the RTH button located on the remote. It's easy to forget their is a RTH button, and even easier to forget you need to hold it down and wait for the beeping instead of just quickly pressing it. Still, the button can be invaluable in certain situations (if you app or phone crashes, for example).
  
  
• The RTH altitude is in meters only, so for those of us who use imperial units, you need to make the calculation when setting the desired height. You can quickly estimate in the field by thinking of 3 feet to every meter (even though it's 3.28 ft/m), but the important thing (as mentioned) is setting the RTH altitude higher than the highest possible obstacle on the way home.
  
  
• The RTH altitude can result in a CRASH if you are flying UNDER obstacles, however. If RTH kicks in while you are flying under an obstacle (bridge, trees, etc), it will ascend to the RTH altitude, which could (and often does) result in a crash. If you know you are going to be flying under obstacles AND within line of sight, then setting the Failsafe RTH to Hover is a very important setting. However, that won't prevent the aircraft from returning to home at low-battery warning (though you should be able to quickly cancel it within the app OR by pressing the RTH button on the remote) if you know there are obstacles above you. BOTTOM LINE is that you always need to be aware of your surrounding and obstacles, and be VERY cautious flying under things.
  
  
• Waiting for the home point to be set properly means also waiting for the GPS to be Strong. Sometimes my Air will quickly connect to 13+ satellites and be good to go, while in other locations it may take longer. Until it has a strong GPS lock, you run the risk of flying away without a properly set home point OR losing control of your aircraft. And with the recent fly-aways that have been posted, it's absolutely essential to make sure the heading of your aircraft matches what the app shows in the map (the arrow should be facing the same way as your physical aircraft... if it doesn't, then you could have a compass problem, which could be catastrophic).