The Cotton-copter is a gadget that works like a helicopter. You won't go really high as soon as you use it because you could just camp in the sky, but it could go 2 blocks up per second. It will use 250 cotton per second, so if you have full cotton (5,000 cotton) you can use it for 20 seconds, which will get you up 40 blocks.
For the Devs: You can change anything that I said like height gain per second, design, or cotton used per second.