Proton-M - Proton-M Enhanced

On 7 July 2007, International Launch Services launched the first Proton-M Enhanced rocket, which carried the DirecTV-10 satellite into orbit. This was the 326th launch of a Proton, the 16th Proton-M/Briz-M launch, and the 41st Proton launch to be conducted by ILS. It features more efficient first stage engines, updated avionics, lighter fuel tanks and more powerful vernier engines on the Briz-M upper stage, and mass reduction throughout the rocket, including thinner fuel tank walls on the first stage, and use of composite materials on all other stages. The second launch of this variant occurred on 18 August 2008, and was used to place Inmarsat 4 F3 into orbit. The baseline Proton-M was retired in November 2007, in favour of the Enhanced variant.

Frank McKenna, CEO of ILS, has indicated that in 2010 the Phase III Proton design would become the standard ILS configuration, with the ability to lift 6.15 metric tons to GTO.

October 19, 2011 the Viasat-1 weighing 6.740 metric tons has been lifted into geostationary transfer orbit by the Proton-M/Briz-M Phase III.