Russian Ministry of Defense has scheduled launch of their latest communication satellite, Garpun. It is planned to utilize Proton rocket from Baikonur Cosmodrome.

Garpun satellite which will be launched on 10th December 2015 is second from series of three satellites (first was launched on 2011) designated to replace old Potok/Geizer satellites. Potok/Geizer was providing communicational and data transfer from Yantar satellites. Last Potok satellite was launched in 2000 and stopped operating in 2009. Constellation of three Garpun satellites should successfully replace Potok/Geizer satellites and let reconnaissance satellites to reach North America and downlink data to Russian ground stations. To provide such possibility, all Garpun satellites should be placed exactly on same orbits like Potok/Geizer. It was possible only with utilizing same launch site, in this case Baikonur Cosmodrome in Kazakhstan.

Garpun is medium sized communication satellite designed by ISS Reshetnev. It is based probably on Ekpress platform, 1000 or 2000 version. Basing on this information it is possible to determine weight of Garpun on around 2400 kg. Satellite is powered by two deployable solar arrays. As communicational satellite it is probably utilizing C band (as Potok/Geizer series), Ku Band or S band transponders complied with dish antennas.

Garpun will be put into GTO orbit by Proton-M rocket with Briz-M upper stage. Proton was modified ICBM missile, designed as three stage liquid fueled (dinitrogen tetroxide and unsymmetrical dimethyl hydrazine) with optional upper stage. Weight of the rocket is 712800 kg with height at 58 m and diameter at 7.4 m. First stage is representing original concept: it is long for 21 m oxidizer tank rounded with six shorter fuel tanks (top of the every fuel tank is covered with conical fairing) and consisting one engine. Engines are able to twirl with 7 degree range for thrust control. Six RD-253-14D14 engines are able to provide 10532 kN of thrust with specific impulse lasting 285 seconds. Second stage (with height at 14 m) is equipped with three RD-0210 and one RD-0211 providing thrust at 2399 kN. Third stage is tall for 6.5 m and is equipped with one RD-0212 with thrust at 613.8 kN. Briz-M is powered by one S5.98M with thrust at 19.6 kN. In such configuration, Proton-M is able to lift up to 6700 kg of payload.