Rokot – Space Launch Report

Rokot - Space Launch Report

Rokot/Breeze KM is a small expendable space launch vehicle marketed by Eurockot, which is a joint venture company founded by DaimlerChrysler Aerospace (Dasa) of Germany holding 51% and Khrunichev State Research and Production Space Center (Khrunichev) of Russia holding 49%.

The first Rokot/Breeze KM succeeded in its Commercial Demonstration Flight premier on May 16, 2000. The three stage, liquid propelled rocket lifted off from LC 133, a former Kosmos 3M pad, at the Plesetsk Northern Cosmodrome, Russia (40.5 E, 62.6 N) at 08:28 UTC. About one hour later, the rocket deployed two 660 kg mass simulators, named Simsat 1 and 2, into circular 540 km orbits inclined 86.4 degrees to the equator.


Rokot’s first two stages are based on the Krunichev SS-19 ICBM (UR-100NUTTKh), which has flown 144 test flights and scored 141 success. Its last failure occurred more than 15 years ago. SS-19 was housed and launched from a tube-type launch transport container that could be inserted into a silo. As a result, the Rokot/Breeze KM launcher is also launched from a transport container, in this case mounted to an above-ground launch pad. Before launch, the two-stage Rokot is erected within its container on the pad. A mobile service tower then moves into place to allow installation of the third stage and payload.

Both Rokot stages burn storable, hypergolic N204/UDMH. Both stages used common tank bulkheads, with the N2O4 oxidizer tank above the UDMH fuel tank. The 17.2 meter long first stage is powered by four Khimavtomatiki RD-0233 cardan-gimballed, turbopump-fed engines. Each produces 48,000 kgf sea level thrust for a total 191,837 kgf thrust at liftoff.

A single, fixed chamber, turbopump-fed Khimavtomatiki RD-0253 engine powers the 3.9 meter long second stage, providing 24,290 kgf thrust in vacuum. An RD-0236 vernier engine, consisting of a single turbopump feeding four gimbaled thrust chambers to provide a total of 1,608 kgf thrust, steers the stage.

Rokot - Space Launch Report

Staging is “hot”, with vernier ignition preceding actual stage separation. Staging is effected by the firing of separation motors mounted on the first stage.

Rokot is topped by a Breeze KM third stage, a payload adapter, and a payload fairing. Breeze KM hangs within an extended interstage section atop the second stage. Breeze KM is powered by a re-ignitable main engine that burns N2O4/UDMH to produce 2,000 kgf thrust in vacuum at a specific impulse of 325.5 seconds. The engine can burn for up to 1,000 seconds. The payload fairing is 2.6 meters in diameter and 3.6 meters long.

Rokot/Breeze KM is 29 meters long and, except for the fairing, 2.5 meters in diameter. The launch mass is about 107,000 kg, of which 1,900 kg can be placed in low earth orbit (LEO).

In operation, Rokot’s four first stage engines burn for about 120 seconds, pushing the vehicle to 3,138 m/sec at an altitude of 60 km. The second stage then burns for about 183 seconds to accelerate the vehicle to 5,660 m/sec at a height exceeding 250 km, still at suborbital velocity. The payload fairing jettisons during the second stage burn, about 186 seconds after liftoff.

Breeze KM performs the first of its three burns immediately after second stage burnout to a velocity of 7,700 m/sec, putting itself into a transfer orbit, 200 x 550 km x 86.4 deg being one example. The vehicle then coasts until it reaches apogee about an hour into the flight.

There, Breeze KM performs a second burn to circularize the orbit. After deploying its payload, Breeze KM performs a third, deorbit, burn to lower itself into a 180 x 550 km orbit from which it will more quickly reenter the earth’s atmosphere.

Krunichev launched an inital Rokot version, Rokot/Breeze K, on two successful suborbital missions in 1990 and 1991 and on one orbital mission in 1994. All flights were from an underground silo at Baikonur. The latter flight put an amateur radio satellite into a 1881 km x 2163 km x 64.8° orbit.

The company held a contract to launch several Iridium satellites, but Iridium’s bankruptcy stalled those plans.

Also read: PSLV – Space Launch Report

Vehicle Configurations

 LEO
Payload
(metric tons)
200 km x 63 deg
200 km
Sun Synchronous
Earth Orbit
(metric tons)
ConfigurationLIftoff
Height
(meters)
Liftoff
Mass
(metric tons)
Rokot/Briz KM1.95 t 1.3 t2 stage Rokot
+ Briz KM 3rd stage
29 m107 t

Vehicle Components

 Stage 1Stage 2Stage 3
Briz KM
Payload
Fairing
Diameter (m)2.5 m2.5 m2.5 m2.6 m
Length (m)17.2 m3.9 m1.3 m3.6 m
Empty Mass
(metric tons)
5.7 t1.485 t1.6 t 
Propellant Mass
(metric tons)
71.45 t10.71 t4.965 t 
Total Mass
(metric tons)
77.15 t12.195 t6.565 t~1 t
EngineRD-0233RD-0253
+RD-0236
S5.98 
Engine MfgrKhimavtomatikiKhimavtomatikiIsayev 
FuelUDMHUDMHUDMH 
OxidizerN2O4N2O4N2O4 
Thrust
(SL metric tons)
191.84 t
(total)
   
Thrust
(Vac metric tons)
 24.29 t
+ 1.61 t
2.0 t 
ISP (SL sec)285 s   
ISP (Vac sec)310 s322 s325.5 s 
Burn Time (sec)120 s183s1000 s 
No. Engines41 Main +
1 4-chamber
Vernier
11
TimeEventAltitudeVelocity
T+0 sLiftoff0 km0
T+120 sStage 1/2 Staging60 km3138 m/s
T+303 sStage 2/3 Staging250 km5660 m/s
T+ sEnd First Briz KM Burn250 km typ7700 m/s typ
T+ 60 minSecond Briz KM (Apogee) BurnApogee 
VariesThird Briz KM (Deorbit) Burn after Spacecraft SepVaries