Its a great idea to be able to communicate so easily. Yes, you want the horizontal tail to be big enough to do its job, but not any bigger, since it would be extra drag and weight. Many newer gliders for radio control and hand launch are making smaller tails, but using a longer fuselage, so the tail effectiveness is still good, but with a very small tail. We hope you can come back and join us for another chat next week. Well, the fastest airplanes go about Mach 3, or 3 times the speed of sound.
Spacecraft go much faster.
Without air resistance, you can go really fast. I think the space shuttle in orbit goes about 20,000 miles per hour. But its really fast. But unfortunately, spacecraft speed is limited by how much fuel you can get up there, which takes bigger booster rockets. Maybe if we stored fuel in a tank up there with several trips, we could get enough fuel to go very fast, like half the speed of light or so - but even at that incredible speed, it would take a long time to reach the nearest star.