Earlier in our trip at Mount Augustus (Burringurrah as it is known by the Wadjari) I clipped an overhanging tree branch resulting in the drone falling into Goolinee waterhole or "Cattle Pool" as the pastoralists refer to it. Robyn swam in and retrieved the craft which had been fully immersed in water for over 5 min. :(
The offending tree pictured below
I dried it out for a week and amazingly most of the central flight control electronics and navigation sensors appeared to be working fine. However on firing up ony three out of four motors came up to spin speed. I figured it was the motors so ordered 4 new ones on eBay to be delivered to Broome post office. Thankfully I had put a gas powered soldering iron in our tool box so was able to replace the motors.
Unfortunately on power up the same 3 motors failed to spin. I figured the next suspect was the ESC (electronic speed control) boards which drive each motor. I swapped the boards between the one motor which worked and one that didn't and sure enough the problem migrated so I ordered 4 new esc boards and had them sent to Derby post office.
After installing 4 new boards I am happy to report the Quadcopter is back in the air and recording footage once again. It has taken me a bit to get my confidence back and the first time I flew over a water filled gorge I was terrified it would fail and plunge into the water again.
I have uploaded some new pics to the flickr group taken since the crash.