I expect this thread to be calm and balanced....
There are two types that will reply to this thread:
1. The ones who think that horseless carriages are just a fad
2. The know-it-all tech nerd that expects it to happen tomorrow.
Lockheed, Boeing, DARPA, and Dassault are actively working on single pilot systems for large and high performance aircraft. Many solutions are designed to bolt onto existing airframes.
Timeframe?
Very difficult to say. Assume 10 years for now.
Some say passenger will refuse to fly on single pilot airplanes.
Yet people willing fly on Spirit to save $5.
Then there's the philosophy:
Single pilot airplane: Is it an unmanned airplane with an biological backup? Or is it an 1 crew airplane with an intelligent autopilot?
Unmanned? probably for cargo.
The navy has drones that respond to hand signals, that may be a step on ground handling.
Datalink communications available to the airlines is also a step to partial or full automation.
The progress of AI is pretty impressive and moving at leaps and bounds.
I'm curious what Amazon and Fedex have in mind. If anyone has a plan, they do.