I have fown in about 15 F and my plane was fine, but I froze my fingers off! It was like trying to play the piano when your hads are frozen, it doesn't work too well. So to solve the problem I made myself a Tx Glove like is mentioned above. It keeps my hads plenty warm allong with the TX and batteries. It also doesn't restrict your fingers like regular goves do. I made mine out of 12oz cotton duck shell, fleese, and synthetic stuffing, it works great! The only problem is that the window sometimes fogs up, but that doesn't matter too much. Here is a pic. It's not pretty, but it works great