Actually, Fireline will stretch, not like monofilament, but it will stretch a little...Spiderwire would be a better choice. It's a braided Spectra line that behaves like Kevlar (extremely high strength, zero stretch) with better flexibility. You can find up to 80lb test line at your local Walmart. It's a little more expensive and doesn't take CA (you'll have to tie and crimp it), but it's great stuff.

http://www.spiderwire.com/

However, I still wouldn't use it on a really large plane (say, larger than 1/4 scale)...I would use 120lb test coated steel leader line:

http://www.tackletogo.com/bersteellead.html