Last weekend I was finally able to get my rov in a test tub and start to test its various performance properties. I really learned a lot, definitely a blast to get it in the water and see it bobbing and spraying around.
I'm really impressed with the power and speed. I'm using a joystick with proportional power control and I can't imagine trying to control it without having that fine control.
Two major things occurred that I found interesting and will be mentally and physically prepared for in the field, brownouts and propeller detachment.
With brownouts I've experienced two different styles, one where the rov recovers and powers back up automatically, and one where the rov stays in the off state until I physically detach power from the batteries. The brownouts only occurred under heavy load and I wasn't sure how fresh the batteries were.
As for the propeller detachment that comes as a surprise. What happened is that the propeller literally unscrewed itself off the shaft when I applied hard reverse thrust at full power. This didn't happen right away, but after a while of me being aggressive with the driving. I think this just highlights how much thrust is being generated, it's waaayyyyy more than I was expecting :)
I'm not quite sure the best way to put the propeller back on once it get's ripped out. For now I've coated the shaft with silicone and slide the prop back one (still a firm fit), then some more silicone between exposed shaft and hub.