Since a pilot is mainly only needed for take off and landing 99.9% of the time, I'd bet not much longer. Getting from an to the ground are the hard parts. Even then, during optimal conditions, you probably don't even need the pilot, so it's likely you'll get pilots monitoring multiple aircraft from take off to landing and only interceding when an emergency arises. In time it'd probably become something they can do from their own homes. Then after they've collected enough data and trained the AI with it, they'll be able to do away with the human pilot altogether.

Any task humans do that don't rely on smell or taste you can train an AI to do. The problem is no longer if you can make a machine smart enough to do it, the problem now is do they have enough data to train it. By making pilots remote they'll be able to gather that data easily. Once we develop sensors that can perfectly mimic taste and smell, humans will only be needed for manual labor.