@alex: i've heard someone say that you need to have both in for the badge. might not be true, but i heard someone say it, and i cant test it either way.
i stopped controling it on day 5 after an hour, and it been going a good few minutes still, staying about same altitude...
i just going to switch windows and i'll post another comment with the results :P
http://FantasticContraption.com/?designId=5658582
look at this one, i mean, holy crap! i had no idea something this "simple" would work. notice how flexible the structure is :P