On its debut flight in Switzerland in June 2014, the plane reached a
maximum altitude of 5,500 feet (1,680 m) and flew
at an average
ground speed of 35 mph (55.6 km / h).
Combined with the Off - Road Engineering package, all GLCs with Air Body Control also get Downhill
Speed Regulation (DSR), adjustable ride height and a significant
ground clearance boost to 227 mm (in
maximum Rocking Assist mode), 50 mm higher from the standard 181 mm, as well as five additional driving modes activated by a dedicated button, placed
at the top of the center arm - rest: Slippery, Trailer, Off - road, Incline and Rocking Assist.