Start (RT-2PM)

ZAO Puskovie Uslugi * United Start Corporation

The Start program consists of two launch vehicles, the Start-1 and the Start. The Start-1 launch vehicle is a converted RT-2PM known as Topol. It is one of the smallest launch vehicles in the world, measuring 22,7 m in height and having a capacity of lifting 0,632 tons to a LEO altitude of 200 km. The Start-1 consists of four stages. The Start launch vehicle is similar to the Start-1 however it adds a fifth stage. Start is larger and has a higher payload capacity, but has not experienced a successful launch. Both spacecraft are unique in that they are the only launch vehicles in the world to use solid propellant for all stages.
Both launch vehicles are operated by ZAO Puskovie Uslugi in Russia and by the United Start Corporation in the United States.
The first Start-1 was successfully launched in 1993, delivering a non-commercial payload to orbit.  The only Start to attempt a launch was destroyed in 1995. The first commercial launch of the Start-1 occurred in 1997, raising its payload of an imaging spacecraft for the Earthwatch Company. As of last June ('99), four successful Start-1 flights have been recorded including its first flight without incident.

The "Start" family of space launch vehicles is derived from the RT-2PM "Topol" intercontinental ballistic missile. The "Start-1" variant, consisting of four solid-propellant stages (RT-2PM plus a new fourth stage) with a maximum diameter of 1.8 m and a height of 22.7 m, was launched from the Plesetsk Cosmodrome on 25 March 1993 with a 225 kg payload. Start-1 has a LEO payload capacity of up to 550 kg. The basic "Start-1" launch vehicle is based on the "Topol" ICBM designated RT-2PM. The second, larger member of this launch vehicle family is not called the "Start-2" as might be expected, but simply "Start."
The RT-2PM and the "Start" family of vehicles were designed by the Moscow Institute of Heat Technology (MIHT). It is the only organization in Russia with the capacity to design and build large solid-fueled motors for strategic missiles and space launch applications. (PO Yuzhmash in Ukraine also has solid-propellant casting facilities). A commercial branch of MIHT, the Scientific and Technical Center Complex or STC Complex (also transliterated NTTs Komplex) is currently responsible for the "Start" vehicles. Manufacturing of new RT-2PM missiles and refurbishing of missiles into "Start" launch vehicles is performed by the Votkinsky Zavod Association plant, located in the Udmurtia region west of the Ural mountains.
The "Start-1" consist of four solid-propellant stages, plus a small post boost propulsion system (PBPS) powered by a nitrogen gas generator for precision orbit injection. The first stage uses jet vanes in the motor exhaust plume to provide initial attitude control. An array of small rectangular grid panels, similar to air brakes found on fighter aircraft, are arranged around the base of the first stage. As dynamic pressure builds, individual panels are angled into the airstream to provide the primary steering forces. The second and third stages have fixed nozzles with gas-injection thrust-vector control. The injected gas deflects the exhaust in the same way that more conventional liquid-injection thrust-vector control systems work. The upper solid stage has a hydraulically gimbaled nozzle for pitch and yaw control, and a gas-generator roll control system. A final PBPS is used for velocity trim at orbit injection. It is powered by a nitrogen gas generator, which presumably feeds both the axial acceleration thrusters and the attitude control thrusters. The primary launch facility for "Start-1" and "Start" launches will be the new Svobodny Cosmodrome in the Russian Far East, near the Manchuria border of China.

Start-1 payload capability from Svobodny (tons):

The multipurpose transportable Start-1 Space Launch System is intended for injection of a small spacecraft into low earth orbits.
The Start-1 Space Launch System (SLS) includes Launch Vehicle (LV), equipment for transportation of LV and launch system elements, and also launch and processing equipment necessary for Launch Vehicle / Spacecraft integration, final preparation and launch.
The solid-propellant Start-1 LV was developed in the early 1990s under conversion of rocket technologies by a group of Russian enterprises leaded by Scientific and Technological Center "Complex-MIHT".
The Launch Vehicle and its systems, as well as ground launch equipment and processing equipment were developed using elements, components and technologies for missile systems with the RT-2PM ICBM, which ensure their high reliability.
Boost Stages Motor of each boost stage utilizes a composite solid propellant. Various composite materials are used in boost stage design.
All boost stages are equipped with gas-dynamic controls in pitch, yaw and roll. 1st boost stage is equipped with both gas vanes and air vanes.
Gas-reaction attitude control system (GRACS) is located at the aft section of the 4th Boost Stage. Working medium of this system is pressurized nitrogen.
The post-boost propulsion system (PBPS) is provided for a final flight phase to achieve required values of SC kinematic parameters at SC separation point. PBPS includes solid-propellant gas generator, ducts, and three pairs of push-operated nozzle assemblies which are installed that burnt products flow out in direction opposite to spacecraft location. These nozzle assemblies are placed outside propulsion module and are sheltered by local protection covers.
On the side surface of the instrumentation compartment body there are two panels of umbilical plugs (UP-1) that are used to communicate onboard equipment (GCS and LV measuring system) with electronic ground support equipment (EGSE).
In case that there are no high requirements to orbit altitude accuracy, the Start-1 LV without PBPS can be used to increase a spacecraft mass to be injected.
Adapter provides mechanical interface between LV and SC. The standard adapter has an aluminum alloy frame-type structure formed by two (front and rear) end rings jointed each other by system of rods. To seal the head module the bottom is installed on the rear ring.
On the front ring of the standard adapter the following devices are installed: three explosive locks for spacecraft attachment; four separation spring assemblies for spacecraft separation; two connectors; two sensors for spacecraft separation monitoring.
Launch procedures are initiated at the point (in time) when the "fire" command is generated to the launch equipment. At this point TLC with LV is in horizontal position on the launch stand or on mobile launcher.
Countdown cycle continues a few minutes. Then the TLC with LV is elevated in vertical position. After the TLC is in vertical position the LV mechanical links with TLC are detached and the solid-propellant hot gas generator is ignited to launch the LV from the launch stand or mobile launcher.
LV is ejected from TLC by pressure of SPHGG burnt gases. The UP-1, which communicates ground support equipment with onboard GCS equipment and LV measuring system, is detached via LV motion.
When LV leaves TLC the sabots and the seal sabot are dropped sequentially and then air vanes and stabilizers are opened.
Following the LV withdrawal from TLC at a safe distance the 1st stage motor is fired. Each boost stage operates about one minute until propellant burnout is complete.
Following the 1st stage motor burnout LV continues flight with inoperative motor at coast phase for 10-20 seconds. On finishing a prescribed coast phase the spent motor is separated and the 2nd stage motor is fired.
Interstage section connecting 1st stage motor with 2nd stage motor is released within 10-20 seconds after Stage 1/Stage 2 separation.
Stage 2/Stage 3 separation and 3rd stage motor firing are performed without coast immediately after the 2nd stage motor burnout.
To place spacecraft in orbit of prescribed altitude the LV flies with inoperative 4th stage motor after separation of the spent 3rd stage motor. At this second (main) coast phase, which extends for a few hundred seconds, the stabilization and programmed orientation of LV are performed by gas-reaction attitude control system (GRACS).
At the main coast phase, LV lateral maneuver is performed to separate fairing using mechanical assemblies and then LV attitude (its longitudinal axis) is returned to the trajectory plane.
When altitude close to a prescribed SC orbit altitude is achieved the guidance and control system generates command to 4th stage motor firing.
At the end of the 4th stage motor burning LV achieves an orbit close to prescribed one. Following the 4th stage motor burnout the post-boost stage is ignited with a small delay (up to 5 seconds).
The post-boost propulsion system operates until burnout is complete.
To the end of the 4th stage motor burning the LV motion program at post-boost stage operation is formed with allowance for real values of LV kinematic parameters in such a way that the LV kinematic parameters conform to prescribed SC orbit with a required accuracy when the post-boost stage burnout is complete.
At the end of PBPS thrust decay the GRACS is activated again to control LV attitude.
The LV is turned so that a required SC orientation to be provided at the separation point.
The GCS generates a spacecraft separation command within about 375 seconds after the 4th stage motor is burnt out. Under that command SC explosive fixing locks are opened and spacecraft is separated from LV using spring assemblies.
Following the spacecraft separation the LV is turned in the SC orbit plane through 90° relative to the SC velocity vector and then LV is rotated by the GRACS.