This is indeed the first water engine in TPT. It burns the hydrogen and oxygen derived from distlilled water with a small amount of gas to produce thrust. I used a TESC sparkplug because there is no other  metal that can recieve a spark from a wall and still burn gas. It's also old-school, no electronics. :)

Note: This wouldn't work in real life. According to the currently accepted laws of physics, there is no way to extract chemical energy from water alone. Most proposed water fuelled cars rely on some form of electrolysis to separate water into hydrogen and oxygen and then recombine them to release energy; however, because the energy required to separate the elements will always be at least as great as the energy released, this cannot be used to produce net energy. Yet again, this law is broken when steam turbines are brought in perspective. 

@R3APER (View Post)

 Luckilly for us in powder toy, no complex mathematical equations are needed to make such devices. You just need creativity and common sense.