Estimating height if trees, utility line. Buildings. Hills and other natural features both nearby and distant.

[Newguy126]

As an ex fighter pilot who flew low level missions, one thing I learned was if you look straight ahead, camera pitch zero, and fly forward, if you see more and more things appearing beyond the obstacle, then you will clear it. You don't need to know it's altitude. Just set camera a degree or two down and watch the display. Go up if you see less of the terrain beyond the obstacle.

 

[Order66]

This is among the most basic flight safety tasks.

Just clear the horizon.

Go up until you think you're above any obstacles around you. Do a 360. If anything is visible above the horizon line, go higher and repeat. Once nothing is above the horizon line, go a bit further as a buffer, and proceed with mission.

 

[Earthman]

Theodolite is a good IOS app for measuring objects on an iPhone, I believe there are droid versions of it too, try searching for theodolite pro.

I also use the Theodolite app on my iPhone to measure 1) the vertical angle between where I’m standing and the top of visible obstacles, and 2) the horizontal distance to the obstacle use the map feature of the app. I plug those two numbers into the attached small spreadsheet I keep on my iPhone to estimate the height and elevation of the obstacle.


Useing the UAV is a good way of estimating the minimum save altitude too. remember that a line between the UAV’s camera and the horizon is a level line, so any obstacle below the horizon is below the UAV while any object above the horizon is above the UAV.

 

[In The Zone]

To be safe just set it for 300 feet and forget it.

UNLESS—you’re flying somewhere with crap above the drone. Then set it to hover in place.

That's probably not a good idea especially if your near airports like I am I want my drone to fly as low as possible if I have to use RTH my highest tree is 86 feet so my RTH is set at 124 feet.

 

[Kaydet]

Can't view the attachments you've included in this post. When I click on each one it takes me back to this screen and post.

When setting return to home setting the proper altitude is necessary so my Mavic Mini doesn't fly into objects in its flight path while coming home so I'd like to know is there an android phone app that can be used to estimate the height of both close by and distant obects such as trees, buildings, ultility lines, etc. which people like me who aren't good at estimating height can use?

I fly with 3 batteries. If I’m in a new location my first flight is to ascertain the height of the tallest obstacle and confirm the camera set up / filter , etc

Up and down in 3 minutes and only uses a few percent on one battery. Then as others have said I add some safety margin, 20 or 30 feet.

 

[DanMan32]

That's probably not a good idea especially if your near airports like I am I want my drone to fly as low as possible if I have to use RTH my highest tree is 86 feet so my RTH is set at 124 feet.

It can also be an issue on windy days

 

[DanMan32]

Using the horizon as a reference works at any gimbal angle but assumes the terrain is relatively flat. If distant objects that you are using as a horizon reference are at significantly higher altitudes, this won't work.

However if you have the gimbal at 0 degrees (level to horizontal) then you can use the center of the screen as your means of measuring obstacle altitude.