LOBBYING: Delta Air Lines joins renewable fuel scrum on Hill Amanda Peterka, E&E reporter Published: Wednesday, October 2, 2013 As jet fuel prices squeezed the aviation industry last year, Delta Air Lines Inc. flew into the refinery business. Please subscribe to Greenwire to read the full story. Username: Password: Forgot your access codes? Recover them. Not a subscriber? Sign up for a trial. Ready to subscribe? Click here.