Drone Down!

You know that moment when you realize you have F%$#@d up badly?  Yeah…it’s like that.drownedphantom

Anyone following this blog will be aware that I received an awesome quadcopter for my 50th birthday.

I’ve had great fun with this little baby ever since it arrived.  In addition to flying and taking video I found myself enjoying modifying it almost as much as flying it.  In three months I added a camera gimbal (these are magic), remote-controlled tilt control for the camera, and upgraded the main camera twice.

Harrison Mountain Lake Dam

Looking for interesting things to photograph from the air I remembered an interesting looking dam out in Ringwood that I thought was perfect.  It has a nice car park next to the water, a tall flag pole complete with the stars and stripes and, of course, the dam and water.

My first visit was a bust due to high winds so I decided to come back another day.  Saturday’s forecast was rain and snow, but the morning turned out bright and sunny.

Since everyone was still asleep I had no chance of recruiting a spotter, but I decided to go for it anyway armed with three fully charged batteries.

I got one flight in and took some nice shots, but I wasn’t happy.  I wanted a better shot flying around the flagpole, and I wanted a high downward looking view directly over the dam.  I put a second battery and managed two very nice circles around the flagpole, which can be tricky.

Feeling cocky then I flew over to the center of the dam (about 100 yards away) and sent it straight up about 200′ to get my shot.  I decided that a circular panoramic video of the area would be good, and that’s where things started to go horribly wrong.

I looked down at the remote as I started a slow rotation so that I could tell when I was fully around.  Unfortunately I had been lazy in my setup of the First Person View (FPV) camera and it was pointing slightly upwards – all I could see was sky.  Since I had already started rotating I now had no idea which direction the quad was facing.

I knew the battery would be getting low and decided to check the battery status LEDs on the copter.  I looked up and…WHERE’S MY QUAD!?

I knew it was there.  I could hear it.  But I had totally lost sight of it.

Normally when things start going wrong the best thing to do is climb and get above things that can hurt you, so I automatically did that.  Unfortunately that just made matters worse.  Now I was looking for a little dot in a very bright sky.

A little panic started to set in and I decided to use a feature called Home Lock.  Home lock should allow the quad to come back to me regardless of the direction it is facing.  I set the mode, pulled back  on the stick and waited…and waited…and waited.  I couldn’t see it and the sound seemed to be getting further away instead of closer.

The upwards looking FPV was useless.  Nothing but sky to orientate myself with.  In desperation I switched on the “failsafe” return to home feature.

This should have caused the quad to fly home and automatically landing where it started from.  It didn’t.

I could still hear it but I was really starting to panic now because I knew the battery must be seriously depleted.

I waited for it to come, desperately scanning the sky.  I could still hear it and see the image on the FPV and then…a sickening silence and a few seconds later the FPV screen said “Connection Lost”.  

What happened?

I’ve had time to reflect on this.  Too much time in fact because I have actually woken up dreaming about this on several occasions.  So, with 20-20 hindsight, here are the things I did wrong.

  1. When I added the GoPro to the gimbal I knew it’s wifi range was short, so I stuck the original FC40 camera on the battery door.  The door is angled slightly upwards and I should have taken the time to adjust things so that the camera always pointed slightly downwards.  Had it been looking down I could have orientated myself better and probably flown the quad home manually when the fancy Home Lock and RTH features failed.
  2. I should have allowed for the fact that dams contain large amounts of rebar.  I believe this may have confused the compass and interfered with the ability to use Home Lock / RTH.  I could have flown it home manually (see above) but autonomous flying should not have been relied upon.
  3. I should have taken a spotter – preferably someone with younger eyes than me.  OK, that’s tough because if I waited for that I’d almost never fly.  But it might have saved the day.
  4. When things went wrong I should not have increased altitude.  While this has saved me other times, in this scenario it just made matters worse.  Instead I should have dropped down as it would have brought landmarks into view of the FPV camera and I could have orientated myself and flown home manually.
  5. I should not have been so lazy / cocky and walked to where I was flying instead of just standing 100 yards away in the car park.  It would have given me a better chance of keeping it in sight.
  6. It was a very bright morning and the ability to see what little information their was on the tablet I was using for FPV was limited.  A cheap cowl would have made a huge difference.

An expensive lesson learned.

Where do we go from here?

As I mentioned at the start I found that I enjoyed working on it almost as much as flying it.  I had already been talking about building one and my daughter was really into building it with me.  The loss of my FC40 has accelerated that project and I am now in the process of putting one of these together:

DIY-Quadcopter

F450 Quadcopter

The parts for this are winging their way to my home from various locations around the world right now.

I had also been helping a friend who has a dead Phantom 1 that he doesn’t have the time to fix.  When he heard about my loss he contacted me and said “If you can get it working, it’s yours”.  Wow!  That really made my day.  No idea if it will ever really come back to life, but I’m betting there’s a good chance.

So, learn from my mistakes.  Don’t be cocky.  Take time to set things up properly.  And bring a spotter when you can.  It could be the difference between a healthy drone and a drowned drone.

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5 Comments

Filed under Building Multirotors, Drones

5 responses to “Drone Down!

  1. Your sad story reminds me why I prefer software. The learning experience and conclusions are similar but errors are easier to fix. It is often cheaper in the long run to write a program, get it working, then throw it away and write a fresh version with what you have learned. You’ve reached that stage in hardware!

    • Very true. It would be awesome to be able to take a backup of the quad before flying and if things go awry just restore and carry on.

      You know the saying. “A ship in a harbor is safe, but that’s not what ships are built for.”

  2. rainabba

    I feel your pain. I have an F550 with the Zenmuse HD3D gimbal and GoPro Hero3+ Black (quite an investment in other words). I’ve had to fully rebuild it twice and the 2nd time I was sure that I was going to hurt someone or get sued because I was flying in my neighborhood, tried to use RTH and didn’t know how to take back manual control at the time which was a problem when my compass/gps receiver got loose, causing the thing to zoom around above my neighborhood at easily 30+MPH. Luckily, it hit a tree and was destroyed rather than someones house, car or person (busy street nearby). I’m now VERY thorough in my pre-flight checks, ensuring I get a good GPS lock and thinking 3 times about where I fly and the potential risks.

    It’s not a cheap hobby in the best of cases 🙂

    • “It’s not a cheap hobby in the best of cases” – Very true.

      I spent a good amount of my flying time trying out different things like Home Lock, RTH etc.
      One day I was experimenting with ATTI mode in my back yard flying it in tight circles. I was used to GPS mode where, when you stop controlling it the quad would stop and wait.
      I let go of the controls and, to my horror, the thing shot off directly towards my neighbors car at high speed! Fortunately it arrested by a well placed evergreen 🙂

  3. Pingback: Building an F450 quadcopter – Day 1 – A lot to learn | Houldsworth's Random Ramblings

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