If you've changed the name of people, places and the airline, I fail to see the problem. I have come across this because I have worked in a previous life with a lot of famous musicians and want to write a tell-all - not necessarily to make them look bad, but for people to see the whole artist, not just a shallow public persona. Anyway the trouble with defending yourself against claims of libel is that you have to prove your case, and in fact I have not kept the incredibly abusive 2am texts etc, and apparently my word is not enough.
There's another aspect which is "restraint of trade" - if you make someone look bad, even if it's true and demonstrably so, you can still be prosecuted (in the UK at least - and presumably you want to be able to sell your book in the second-biggest English speaking market) if your truth-telling adversely affects the person (or possibly company too)'s ability to make a living.
I would check with a lawyer - cos it's also possible that your tale doesn't fall foul of any of this, and not only can you publish, but you can name the airline and co-workers. I think it would be a shame if you don't, btw, cos otherwise it's a novel but constrained by the banality of real events. If it's set at "Columbia Airlines", "Trans Global Airlines" or "Astral Horizon Airlines", you may as well throw in a few crashes and a trans-gender Head Of Flight Ops.
fly Saha Air 707s daily from Tehran's downtown Mehrabad to Mashhad, Kish Island and Ahwaz