Your needle has to face away from the hook, so the hook can pick up the thread from the back of the needle.
Wait.... Are you talking about the needle with the slit on the side, so you just slide the thread along the side and it goes in? It's called a "Handicap" or "Quick Threading" needle. I've never seen one for a longarm, and just checked my sources, and couldn't find one. Longarms may move too fast for that type of needle.