A blonde was taking helicopter lessons. The instructor said, "I'll radio you every 1000 feet to see how you're doing."At 1000 feet, the instructor radioed her and said she was doing great. At 2000 feet, he said she was still doing well.Right before she got to 3000 feet, the propeller stopped, and she twirled to the ground. The instructor ran to where she crash landed and pulled her out of the helicopter. "What went wrong?"The blonde said, "At 2500 feet, I started to get cold, so I turned the big fan off."