Tesla had earlier teased this event, while keeping the content under wraps, with the letter D. Here we see the stage set for the event at the Hawthorne Airport in the Los Angeles area.
Tesla CEO Elon Musk takes the stage like a rock star looking down at his adoring fans.
The Model S 'D' chassis was raised up on a robot arm for the event.
The chassis showed how the D option for the Model S includes dual motors, one at the rear and one at the front.
Musk posted this slide, showing the dual motor arrangement. On-board software monitors the wheel slip and other parameters, telling the car how much power to apply at each axle. Musk said the car accelerates to 60 mph in 3.2 seconds.
A standing chassis on display shows the standard Model S motor at the rear wheels.
The front wheels get a smaller motor.
Test drives given at the event started with a fast launch of the car.
Musk also announced Autopilot capability in the Model S. All recent Model S cars have radar, camera, and ultrasonic sensors built in.
These sensors enable adaptive cruise control, automated parking, and lane keeping assist. The dashboard, shown on this slide, shows the driver where other cars are in proximity to the Model S.
Musk mentioned that the car's electric power steering creates the ability to self-steer.
Likewise, electro-mechanical brakes on the Model S allow for precise computer control.
And finally, the Autopilot software can control the drive motors better than it could an internal combustion engine.