All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
You are allowed to work with an airline that serves alcohol as long as you do not assist and are not directly involved with such a service.
So, you have to be a good staff member who may contribute to the reformation in this firm.
We ask Allah to help you and grant you success.
For more benefit on the prohibition of alcohol in Islam, please refer to Fataawa 81900 and 81389.
Allah knows best.