Disability Travel - airfare for disabled vet

My husband is a 70% disabled vet, but not a retired 100% disabled vet. Which airlines offer discounts on airfares or are there free fares out there?

http://www.ehow.com/how_2096170_get-veteran-travel-discounts.html

http://answers.yahoo.com/question/index?qid=20081230102111AA8Jyzg

http://www.city-data.com/forum/retirement/1552453-disabled-navy-veteran-would-my-uncle.html