Wow, I can not believe some of the advice being giving here.

You do not need to stab him in the back. All that will do is get one of you fired and both of you on edge with each other.

Be an adult, sit him down, and talk to him about the problem. Have a rational conversation that goes both ways. Listen to his opinion also.

If that doesn't change anything then go to the aircraft owner and once again talk about the problem.

If neither of these fix the problem than perhaps it is time to re-evaluate your current job.