Flying under ground?

Chuck Young · Aug 20, 2015

So I have been asked to fly a vertical concrete tunnel to look for the source of a water leak. The tunnel is bout 30 feet in diameter and is about 270 feet down. I will take off from the bottom and fly up looking at the concrete walls on the way up for the origin of some water leaks. It is really dark so my P3P needs some additional lighting. I am pretty much an amateur at this so lots of suggestions are welcomed. I have not flown the P3 any mode but P so lots and lots of practice in A and F mode is necessary. I probably have a little over 50 flights on the P3 but also have a Hubsan I fly constantly so I sort of know what to expect. I will be doing lots of practice and will moving forward only when I feel comfortable with each step in what I foresee as a long process. Good news is I have all the time I need to get this done.

My first step would be taking baby steps out of P mode which leads me to my first brick wall. I can get it in A and F mode in the app but when I try to start the motors I get an error message about calibrating the compass. That is not going to happen considering I am almost 300 feet under ground, in a 30 foot shaft with huge metal objects everywhere around the aircraft.

So any suggestions?

robsquad · Aug 20, 2015

possibly the only use for prop guards i can think of

Chuck Young · Aug 20, 2015

robsquad said:
possibly the only use for prop guards i can think of

I live at 8000 feet right in the middle of the high country of the high country surrounded by 13 and 14,000 foot mountains and forests. Absolutely nothing is level and rocks are everywhere. I would own a prop company by now If I did not use prop guards. lol

thanks for the suggestion though, they will be on in the tunnel. Kind of wished I had a real bright light bulb and a second spherical camera for navigating.

C0ps · Aug 20, 2015

I wouldn't risk it unless the pay covers my drone. No way to drop a camera from the top?

Chuck Young · Aug 20, 2015

C0ps said:
I wouldn't risk it unless the pay covers my drone. No way to drop a camera from the top?

I will only do it if I am real comfortable with the whole (hole) process.

logbuilder · Aug 20, 2015

Trying to think out of the box...

For lights so the camera will work, how about a couple of AA Maglites taped to the landing gear facing frontwards.

I would wonder how you are going to tell anything about attitude and orientation. Hopefully you will be able to see your red and green lights for orientation. For attitude, how about a laser pointer taped to the landing gear pointing straight down. You could then look on the ground to see where it is. I realize that it might be dangerous if you looked directly at the laser but I'm pretty much assuming you will be using your camera rather than looking up. This idea is surely not the best but just a thought you might be able to expand upon.

Wibble · Aug 20, 2015

Forget lights on the drone I tried that didnt work too well. I would use a seriously powerful spotlight - something like a 150w KC Day lighter. should illuminate the whole shaft from the bottom up.

Chas · Aug 20, 2015

No fun! But why not just bring the drone up with a line? That would allow any lights needed and you can measure exact location!

Cica · Aug 20, 2015

Chas said:
No fun! But why not just bring the drone up with a line? That would allow any lights needed and you can measure exact location!

+1

Chuck Young · Aug 21, 2015

Chas said:
No fun! But why not just bring the drone up with a line? That would allow any lights needed and you can measure exact location!

I will entertain this idea. So it is 300 feet or so top to bottom. What rope/string do you use and how do you get it and your camera/P3 up/down the hole and point anything anywhere? Just not seeing it happen.

Cica · Aug 21, 2015

Use a piece of pvc pipe as a bar and lower the unit with 2 Mason lines. On top, have a second pvc pipe and small pulleys and small cleats to tie off the lines. The orientation of the top pipe will match the orientation of the bottom pipe.

Dtalbot34 · Aug 21, 2015

Stay on top of the drifting since you won't have GPS in a tunnel.

Sent from my iPhone using Tapatalk

iquadtography · Aug 21, 2015

Is it worth risking your pride and joy? $

damitjim01 · Aug 21, 2015

Chuck Young said:
What rope/string do you use

Fishing line should do just fine

Fourprops · Aug 26, 2015

Build an large X frame out of some pipe or sort. So it extends across and a little beyond the diameter of the pipe, In the center of the X mount a pulley. Secure the P3P under the X run the rope across the length of the X frame legs so it holds the phantom up with some help carry the the X frame and position it over the opening. Shine your lights down the sides of the pipe wall and slowly lower the P3P down may need a second line to keep it stable. When you find you leak or leaks mark the rope and paint a mark on the lip of the pipe. My 2cents.

acherman · Aug 26, 2015

1 - If I was nearby I would fully volunteer to rappel down there for you. I have been doing tower work for ~18 years, and one of my first big jobs was fixing Christmas lights on the side of a skyscraper downtown in a city. Scary going over the edge. haha That was the gateway drug to rock climbing and canyon rappelling.

2 - Buy a DJI Matrice 100. Don't they have obstacle avoidance? Should make it easier to stay away from walls.

3 - Sorry, none of these are real solutions for you. But, yah, might be best to use a rope and a spreader bar setup.