Anything can be a remote controlled airplane, and ‘copters – quad or not – simply beat the air into submission. Remote controlled cars are easy, and RC tanks can even shoot their guns. One type of vehicle has eluded remote control hobbyists to a large extent; building a remote control submarine is hard. Not only do you have buoyancy to worry about, but you also need a way to keep the dry parts dry, all while operating in an environment where radio doesn’t really work well.
[Ivan] has already built RC planes, but wanted to tackle a new challenge. He built an RC submarine, and he did it using the simplest household materials.