Mercedes-Benz's redesigned S-Class - that debuts this autumn in Europe and reaches the US early in 2006 - is 1.7 inches longer, almost an inch wider, and more than three inches longer in the wheelbase than its predecessor.

The flagship S600 has a V12 engine with more than 500 hp while the 382 hp S500 has the first of a new-generation V8 engine family featuring increased displacement, four-valve-per-cylinder technology, variable valve timing and a lightweight crank assembly. Both horsepower and torque are up considerably, yet with lower exhaust emissions and noise.

The new S-Class comes with the world's first seven-speed automatic. A small lever on the right side of the steering column  controls the transmission in a similar manner to that in the BMW 7-series - lift the stalk up for reverse, push down for drive, and push a button on the end for park.

Once underway, shift buttons on the back of the steering wheel provide touch shift manual shifting. An electronic parking brake is engaged at the push of a button on the dash, and is released automatically when the driver shifts into gear and touches the accelerator.

Just before a possible impact, the front seat belts are automatically tightened, the sunroof closes, and the passenger seats can move to positions that provide better protection -- three measures that have been part of the S-Class pre-safe system since its debut in 2002. On the new S-Class, side windows also close to provide better support for the window curtain air bags, and special seat cushions can inflate to provide greater lateral support for occupants and help the side air bags provide even better collision protection.

The well-known Distronic cruise control feature that maintains a pre-set following distance behind the vehicle ahead is replaced by an optional Distronic Plus system. Integrated with pre-safe, the radar-based system operates at nearly all speeds up to 125 mph and can be especially helpful in stop-and-go traffic. Distronic Plus works with a new brake assist plus system to monitor traffic conditions, and if a collision is anticipated, ideal brake pressure is applied, even if the driver applies the brake pedal too lightly. In extensive tests using 300 drivers, the new system - another claimed Mercedes-Benz safety first - reduced rear collisions in heavy city traffic by 75%.

Distronic Plus also incorporates 24 GHz radar-based park assist. This new option utilizes six radar sensors mounted behind the front and rear bumpers - eliminating the need for the visible portholes of the previous ultrasonic- based system. The result is clean, integrated, and invisible with greater range and sensitivity.

Another innovative technology making its debut on the new S-class is infra-red night vision, a new option that can extend the driver's visibility to nearly 500 feet.  An industry first, and in contrast to passive systems offered by other auto companies, this active system bathes the road ahead with infra-red light from two projectors mounted in the headlight assemblies.

An infra-red camera mounted in the windshield receives the reflected images and displays them in the high-resolution display in the instrument cluster. The result is akin to a highly detailed black & white video image.

The centrepiece of the dash is an eight-inch high-resolution display for an intuitive new Comand system, now positioned at the same height as the primary instruments and operated by a controller (similar to BMW's I-Drive wheel) located on the lower centre console. Instead of requiring occupants to use the system exclusively, many vehicle controls are accessible by conventional hard keys, the multifunction steering wheel, and optional voice control as well as via the Comand system.

Newly developed front seats are electrically adjustable 16 ways and offer several optional choices of ventilation and ergonomic adjustability. The available Drive Dynamic seats feature 11 individual pneumatic chambers to help the driver find a perfect seating position, and 14 more chambers provide four levels of pulsating massage to relieve fatigue and help keep drivers alert.