crunch can generate all possible combinations of your 8 character password. If you were to try to save crunch's output to a file the file size will be: 1750GB.
(x^y) * (y+1) = size in bytes
x is the length of the string 8
y is the length of the character set 26
(8^26) * (8+1) = 1750GB
You probably want to pipe crunch's output to aircrack like the following untested command:
/pentest/passwords/crunch/crunch 8 8 -f /pentest/passwords/crunch/charset.lst ualpha -u | aircrack-ng -e test -w - /pentest/wireless/aircrack-ng/test/wpa.cap