Audi is testing its next-generation flagship SUV – the Q7. Spy photographers captured images of a prototype undergoing handling tests near the Nurburgring, Germany.Spy images reveal beefier fenders and shorter overhangs. There appears to be major changes to the grille and rear. IMAGE GALLERY: 2014 Audi Q7 (Spy)The Q7 will ride on the Volkswagen Group’s third-generation SUV platform. The platform, derived from the MLB architecture will also be used in the Bentley SUV due in 2016.Engines include 3.0 - 4.0-litre TFSI units, 3.0 TDI and a plug-in hybrid model is also in the works.Much like the new Range Rover, the Q7 is expected to be a lot lighter when it arrives on the market, with the car set to lose about 400kg due to the automaker's use of aluminum, composite materials and smaller engines.While the VW Group is already familiar with such a process (as seen in the VW Touareg and Porsche Cayenne), its engineers now face more and more challenges, as the competition in the SUV segment is fiercer than ever.The new Audi Q7 will be launched in 2015.