Fantastic! The Javelin is a good flyer. I've built two of them. (The first one, I put a Jetex motor on. Worked fine until it went into a loop and tore the wings off!) My second one, 40 years later, flew beautifully with rubber power.
You have done the remarkable I made a couple of stick and tissue planes when I was little, I put a .049 Cox motor on a British Spitfire, and flew it free flight. It actually went a couple of miles then set down on the freeway. It had a brief carrier needless to say. But it was fun, and I still have the memory after 55+ years