What is the ruling on working as a pilot if there is alcohol on board that is given to whoever requests it?

If working on managing the airplane does not involve assisting sinners in their disobedience or condoning it, then there is no harm in it. The general principle is permissibility. The presence of alcoholic beverages inside the airplane does not render this permissible profession unlawful. However, one must denounce the wrongdoer who consumes alcohol in a manner appropriate to one's ability to effect change, as the Prophet (peace be upon him) said: "Whoever among you sees an evil, let him change it with his hand; if he cannot, then with his tongue; if he cannot, then with his heart—and that is the weakest of faith." Preventing the practice of a permissible job that does not aid in sin, merely because some people commit sins within it, constitutes a restriction and hardship that Islamic law does not approve.