Mapping 850 acre site

[Kristina Fowler]

I've been asked to map (ortho) an 850-acre site. It's the largest parcel I've ever done - by far. The longest dimensions are 7,800 ft (north/south) and 9,900 ft (east/west). I'm laying out the mission in front of me and estimate I can chop it up into reason sections, using multiple Drone Deploy missions (with overlap) with the longest distance from home at 2,000 ft. Altitude: 400 AGL.

My question: if I maintain line-of-site, should I expect connection issues with the drone 2,000 feet away? I would position my controller antenna directly perpendicular to the drone at all times.

Thanks in advance. Nervous...

 

[BigL]

What aircraft are you flying? I fly P3Ps all the time without connection issues at 2000 feet.

 

[BigAl07]

It totally depends on what UAS you're flying. A DJI Spark you'll have issues. Most likely anything from a P3Pro and up you should be good to go at 2000'.

 

[Kristina Fowler]

I'll by flying a P4P. Thanks...

 

[R.Perry]

I have flown my Inspire 2 well beyond 2000 feet with no issues, but it will be a dot in the sky. Never flown the Mavic that far out. What I have done on large sections is break them down to less than 200 acres and fly each section from two different home points. That seems to always keep it in sight.

 

[Rob Hodges]

You'll be fine for control and video, but not so good on keeping visual sight of it, if you take your eyes off of it for a second.
It's much easier to maintain sight than re-aquire it.
It also depends on the background and color.
I've lost my grey P4P pro at 300 feet with trees behind it, which is why I installed a brighter skin on it.

Breaking the property up is never a bad option.

 

[JimD]

2000 feet won’t be a problem if you make sure you’re standing out in the clear I don’t let trees get in the way.
How many batteries do you have? Because it’s tempting to let your battery go low when you’re near the end of a section but that’s a good way to lose it.

 

[LeeB]

You may want to consider a white strobe light on the bottom of your aircraft to improve VLOS.

 

[Ajkm]

The chances of maintaining VLOS at 2,000ft are very small.

 

[R.Perry]

The chances of maintaining VLOS at 2,000ft are very small.

That depends on a couple of factors, size of drone, and pilots vision.

 

[Pawel]

2000 feet won’t be a problem if you make sure you’re standing out in the clear I don’t let trees get in the way.
How many batteries do you have? Because it’s tempting to let your battery go low when you’re near the end of a section but that’s a good way to lose it.

Trees might pose a real problem here. It looks like there are a lot of dense forrests at your flight site. I am not sure you see P4P at all from 2000 ft. It is a small bird which will resemble a little dot at best from that distance. If you loose the sight it will be very difficult to get your eyes back on it. Controlling your bird, knowing where is front/back and right/left of it may be difficult.

 

[Ajkm]

That depends on a couple of factors, size of drone, and pilots vision.

It needs a large drone, perfect atmospheric and location conditions and lighting, and 20/20 vision. As I said, the chances are very small of maintaining VLOS, especially given the almost 100% tree background.

 

[Pawel]

It is going to be a lot of flying for you. I have made a little exercise and have looked up what you are up to using Pix4dcapture. Believe DD will yield similar results. 850 acres at: 400 ft and 80/75% overlap and fast speed means app. 130 min of flying only. Assuming P4P endurance of 15 min (am not sure though) it will eat 8 batteries at least. Since there are a lot of forest you may need to have high overlap otherwise stitching can be problematic.
All this will probably needs longer flight time and more batteries as for simplicity I assumed you are to fly a perfect square which you are apparently not going to do. And I have not calculated in any margin for anything going wrong.
In my opinion big sites are to be flown by fixed-wing or VTOLs

 

[JimD]

When you take into account flying back to change a battery and flying back out to where you left off 15 minutes is generous.
And if it’s windy maybe less.

 

[Pawel]

When you take into account flying back to change a battery and flying back out to where you left off 15 minutes is generous.
And if it’s windy maybe less.

All in all - it will take even longer and more batteries.
Does it remain practical then to use a copter for such big sites?

 

[JimD]

All in all - it will take even longer and more batteries.
Does it remain practical then to use a copter for such big sites?

Yes because they’re much more affordable. And have much better third-party support

 

[Pawel]

Yes because they’re much more affordable. And have much better third-party support

Yes they are.

 

[Kristina Fowler]

I’m considering a fixed wing aircraft and a couple of DSLRs. There are 80 foot pine trees all throughout that site. Maintaining an unobstructed line between controller and P4P is a big concern… even at 400 ft. At the end of the day, it’s more efficient and less time consuming with a fixed-wing Cessna and the images are more “brilliant“, in my humble opinion. It should also be noted that it comes in at about the same price.

 

[JimD]

I’m considering a fixed wing aircraft and a couple of DSLRs. There are 80 foot pine trees all throughout that site. Maintaining an unobstructed line between controller and P4P is a big concern… even at 400 ft. At the end of the day, it’s more efficient and less time consuming with a fixed-wing Cessna and the images are more “brilliant“, in my humble opinion. It should also be noted that it comes in at about the same price.

Interesting how do you ensure you’ll get the proper overlap for the customer? I’d be interested to know. Also make sure you have a GPS on your cameras that will tag each picture otherwise the stitcher won’t know what to do.

 

[Kristina Fowler]

The client is hellbent on a final nadir (ortho) image but has no practical reason for doing so. The client will eventually down-size it to 1920x1080. They have no use for survey-related functions that come with the ortho. All they really want is to capture the entire area in one image for an online brochure with no zoom capability. IMHO, I think a nice oblique image is a more flattering look and shooting from a slight angle (about 20 degrees from perpendicular works best. As good as P4P cameras are, DSLR's still have the upper hand in color range and overall "brilliance".

I simply have to talk them out of the ortho.