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10.3.6
Proton
The Proton launch system, built by the Khrunichev State Research and Production
Space Center, is the largest Russian launch vehicle in operational service. It has
10.3
Typical Launch Vehicles
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been used in more than 325 launches and the booster has a reliability record of
96%. Proton launches all Russian geostationary and interplanetary missions under
Khrunichev, establishing it as the principal workhorse of the Russian space pro-
gram. International Launch Services (ILS), based in the United States, markets
commercial missions on the Proton. ILS is a joint venture of Space Transport Inc.
and Khrunichev. The ILS joint venture has launched over 40 Proton missions since
1996.
All Proton missions launch from the Baikonur Cosmodrome, which the Russian
government leases from the Republic of Kazakhstan. The first test launch of the
original two-stage Proton took place in July 1965, when it was used to launch
the four Proton satellites for which the vehicle was named. Last flown in 1966,
the two-stage Proton was succeeded by the three-stage Proton K and the four-
stage Proton K/Block DM launch vehicles. The current version is the upgraded
Proton M with the Breeze M upper stage. An Enhanced Proton with the capability
to lift more than 6 metric tons was introduced in mid-2007.
The Proton first stage consists of a central assembly containing an adapter,
oxidizer tank, tail section, and six lateral assemblies. All the lateral assemblies are
similar in design. Each assembly includes a fore section, fuel tank, and tail section
where the rocket engine is fixed. The first stage is powered by six RD-275 single-
chamber cruise liquid propellant engines developed and manufactured by NPO
Energomash. The propulsion unit develops 9,600 kN thrust at liftoff. The second,
cylinder-shaped stage includes an adapter, propellant section, and tail section. The
thruster facility of the second stage includes four similar sustainer liquid propellant
engines: three RD-0210 engines and one RD-0211 engine—all built by KBKhA.
The nose bay hosts six solid-propellant retro motors.
The rocket’s third stage is a cylinder-shaped structure that includes an equip-
ment bay, a section of fuel and oxidizer tanks, a sustainer engine fixed on the fuel
tank, and an aft bay with a steering motor inside. The aft bay accommodates four
solid-propellant retro motors. The propulsion unit of the RD-0212 third stage
consists of an RD-0213 sustainer liquid propellant engine and a four-chamber
RD-0214 steering engine. In terms of design and operating principle, the sustainer
engine is similar to the RD-0211 engine of the second stage: in fact, the 0213
version is a modification of RD-0211. The space head (satellite, adapter, and
fairing) is attached to the nose section of the third stage booster by the lower ring
of the upper stage (structural interface). The flight of the first and second stages
is controlled by gimballing main engines, while the third stage is controlled by
gimballing four chambers of the steering thruster.
In an effort to enhance performance and reliability of missions to GTO, Khruni-
chev has developed, tested, and commissioned the Breeze M upper (fourth) stage.
The compact design of the upper stage includes a core section surrounded by a
toroidal auxiliary section of propellant tanks, which is jettisoned in flight following
depletion. The 14D30 liquid propellant sustainer engine is mounted in a recess
provided in the fuel tank of the core section. The engine can relight many times
during flight. Low thrust liquid propellant engines use the same propellant as
the main engine. These engines also control orientation and stabilization during
unpowered flight and serve to settle the propellant in tanks as required for restarting
the sustainer engine.
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Launch Vehicles and Services
Installed in the equipment bay on top of the core section, the inertial control
system is intended to control the Breeze M and its onboard systems during flight.
The Breeze M upper stage accommodates the power supply system and avionics
used for telemetry data transmission and trajectory measurements.
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