I really need some advice. Can you help?

So I have a problem, I'm 15 and my little sister is 8. Whenever she ticks me off I usually hit her or yell at her, recently my dad got fed up and said the next time I hit her or made her scream he would beat me so much that social services would have to take me away. He was very serious about it and my mom even agreed with it. So today I hit her for a few reasons, she flipped and called my mom who in turn called my dad who is usually on the road but right now he is about 3 hours away. After that happened my little sister told me she started TRYING to make me mad so I hit her so I would have to leave the house cause of my dad. I told my mom and she yelled at my little sister and then said that she would try to talk my dad down to not kill me. I kinda need a backup plan just in case she can't. I am near the really deep country so I have an option to run away, and I know there is no way I can talk my dad out of beating me senseless. I am so-so in wilderness survival, but I really don't want to turn to that. I just want some advice on how to get out of it so that I can stay at home. (Oh and I don't hit my sister often, like once every 3 months) So I really don't know what to do and how to do so. Can you give me some ideas that I can work off of?