1. Soviet R-7 Semiorka (Little Seven)

2. All were incapable of reaching other continents or reaching orbit
Soviet R-7
Background
Early Soviet missile development programs included the first long-range surface-to-air missile, and the increased range and later submarine-launched R-11
The first nuclear warhead missile, the R-5 also evolved directly from the R-1 / V-2
All were incapable of reaching other continents or reaching orbit

3. The ICBM request was approved in 1952 by Stalin’s decree
Soviet R-7
Background
Korolev' knew what capabilities were needed for both an ICBM and reaching orbit and requested permission to build the first intercontinental ballistic missile (ICBM)
The ICBM request was approved in 1952 by Stalin’s decree
The new R-7 missile was a new-generation, heavy-lift booster that was the first large rocket not derived from Germany's V-2

4. R-7 Design

5. Soviet R-7
Following the government decree of February 13, 1953, the design bureaus under Korolev's OBK-1 began a preliminary design of the two-stage long-range missile
Early specifications for the R-7 launcher were for a nuclear warhead payload capacity carried over intercontinental distances
170 ton vehicle mass
3,000 kg payload
Range of 8,000 km

6. Four external booster segments comprised the first stage (Stage B)
Soviet R-7
Korolev’s initial design for the R-7 had two stages ignited at the same time
Four external booster segments comprised the first stage (Stage B)
Stage A was the second stage called the core stage
The booster and core design was based on several models of Helmut Grottrup, a German engineer brought to Russia with the V-2s

7. Soviet R-7
The R-7's engines also used a German design for the combustion chambers
R-7’s core and booster stages employed a four-engine cluster designed by Glushko
Originally the engines for core and booster were specified as a single engine rated at 65 ton thrust
Designated RD-105/106

8. Soviet R-7
Because of combustion instabilities in the large thruster design, Glushko configured four 25 ton thrusters in the RD-107/108 clusters
A single turbopump was designed to feed fuel and oxidizer to all four engines
Simplified the propellant feed, but the multiple chambers and a single pump shaft was a potential problem for reliable engine operation

9. Improved guidance during the thrust phase
Soviet R-7
Korolev also felt that the four-engine unit required steering thrusters to achieve the needed warhead impact accuracy
Improved guidance during the thrust phase
Improved impact accuracy by steering the missile after booster cutoff

10. Soviet R-7
RD-108
RD-108 core engine contained four 25 ton engines with four smaller vernier outboard engines for impact guidance

11. Soviet R-7
Photo of the assembly line for the R-7 at the Baikonor facility. The core module and RD-108 engine is on the right, a single booster with a RD-107 engine is on the left

12. Soviet R-7
RD-107/8
Four RD-107 booster units and a single RD-108 core engine are shown on a recent Soyuz booster, an almost identical design of Korolev’s R-7 ICBM

13. Four for the core RD-108 module
Soviet R-7
In the completed design, both the RD-107 and RD-108 had vernier guidance thrusters
Four for the core RD-108 module
Two for the RD-107 used on each of the four booster modules

14. The RD-107 and 108 engines had a two-phase startup and operation cycle
Soviet R-7
The RD-107 and 108 engines had a two-phase startup and operation cycle
Began with the main thruster starting with simple gravity feed for the fuel and oxidizer injection into the combustion chamber
As the propellant flow increased, the turbopump accelerated and forced hydrogen peroxide liquid into a gas generator for even greater pressure that drove the turbopump faster
After reaching operating speed, the engines sustained the normal thrust levels for liftoff and ascent

15. Soviet R-7
Supporting trusses on the launch pad held the rocket down until full take-off thrust was developed, about 10 seconds after ignition
During flight, a special system synchronized the fuel consumption of the four strap-on boosters to keep the rocket's weight in balance
Radio guidance sensors and control commands were used for testing and guidance of the missile during early flight

16. Soviet R-7
Glushko's quad cluster design provided 100 tons of thrust in addition to the guidance thrusters that were also fed by the same turbopump unit
Regenerative cooling of the exhaust nozzle was accomplished by circulating kerosene before its injection into the combustion chamber

17. Soviet R-7
Fuel and oxidizer for the R-7 was LOX and kerosene which had a 250 sec specific impulse
Glushko felt strongly that rocket fuels should be used that could be stored at ambient temperatures instead of at cryogenic temperatures
This disagreement persisted throughout Gluskko’s personal conflict with Korolev

18. Soviet R-7
The RD-107 weighed only 25 percent more than the V-2 engine but developed over three times as much thrust
The outer wall of the RD-107/8 engine was steel and the inner wall was a chromium bronze alloy 6 mm thick
5 mm deep channels were milled into the chamber to conduct a flow of kerosene for regenerative cooling

19. Soviet R-7
The 3.8 ton-thrust verniers were designed by Mikhail Malnikov which later evolved into small upper stage engines for their lunar and manned vehicles (Mitchell)
The four combustion chambers shared a 3,800 kW (5,000 HP) steam-powered turbopump
A common drive shaft turned pumps for kerosene, liquid oxygen, hydrogen peroxide (for steam generation), liquid nitrogen (for tank pressurization) and pumps for the vernier engines

20. Design (overall) S. Korolev OKB-1 Bureau
Soviet R-7 Specs
Design (overall) S. Korolev OKB-1 Bureau
Engine design V. Glushko OKB-456 Bureau
Control system N. Pilugin NI-885 Bureau
Vehicle length 28 m (without upper stage)
Weight 280 metric tons (wet) tons empty
Fuel Refined kerosene (T-1)
Oxidizer Liquid oxygen (LOX)
Stage 1 4 strap-on (external) boosters, each with a 4 engine cluster = RD steering engines
Stage 2 Core (center) module - 4 engine cluster = RD steering engines
Range 8,500-8,800 km
Stage 1 burn sec
Stage 2 burn sec

21. R-7 Testing and Qualification

22. Soviet R-7
The first launch of the R-7 was on May 15, 1957, two months after delivery to the pre-launch processing facilities in March 1957
The flight was successful until a strap-on booster separated at T+98 seconds, creating instability and producing a complete breakup
A second launch test was made on 11 June, 1957, with a failure due to a Stage A propellant pressurization problem

23. Soviet R-7
The third test launch was made on 12 July, 1957, but failed 33 seconds after liftoff due to a control circuit error
A fourth launch was made on 21 August, 1957 with Nakita Kruschev present
Although the launch was called a success, a complication with the warhead separation led to an impact with the vehicle
This first launch of the R-7 was immediately announced as a successful launch of the world's first ICBM

24. Soviet R-7
U.S. military planners and the Eisenhower administration realized they were far behind the Russians with their Atlas ICBM program
This was the birth of the “missile gap” that, while political and not supported by missile and warhead count, led to rapid weapons buildup on both sides

25. Soviet R-7
R-7 ICBM
A second verification test of the ICBM was made on 7 September, 1957 to qualify the R-7 for the Sputnik satellite launch
The qualification testing for the Soviet's ICBM role continued until acceptance and deployment in 1960
Even after the R-7 systems were refined for use as a reliable, accurate ICBM weapon, the missile was never deployed in significant numbers

26. R-7 telemetric warhead used for development and testing of the ICBM
Soviet R-7
R-7 telemetric warhead used for development and testing of the ICBM

27. Soviet thermonuclear warhead used on the R-7 ICBM
Soviet R-7
Soviet thermonuclear warhead used on the R-7 ICBM

28. Soviet R-7
ICBM (cont.)
Fueling was time consuming and a tanking would be useful for only 24 hours after which it would have to be drained, re-eximined, and if necessary refurbished, and then cycled which took another 36 hours
This tripled the number of R-7s that had to be online for nuclear weapons strategic deployment
In addition, the R-7 required above-ground launch facilities made it vulnerable to attack or even sabotage

29. Soviet R-7 ICBM
ICBM (cont.)
By August of 1961, there were only four R-7 ICBM's in operational service
This included two missiles in storage the two operational launch pads at Plesetsk
The R-7 was removed from service as an ICBM in 1967, but continued on in space launch applications and are still used today

30. R-7 Conversions

31. Soviet R-7
Korolev's R-7 has had unmatched success as a launcher, from the early ICBMs to today's Soyuz and Molinya boosters
Between 1957 and 2000, over 1,628 R-7s were launched with a success rate of 97.5% for production models
The R-7 was also adapted for use in the first Russian manned flights with a larger third stage added for boost into orbit

32. Soviet R-7
The Vostok booster configuration, also called the Vostok, had a payload capacity of 5 tons
An even larger third stage booster increased the payload to 6 tons to accommodate the Voshkod and later the Soyuz manned vehicles
As of 2010, every manned Russian or Soviet spaceflight has been launched by an R-7 derivative

33. Soviet R-7
Launch test of the Vostok capsule and Vostok launch vehicle, one of the many R-7 derivatives

34. Soviet R-7
A Soyuz launch vehicle and mated Soyuz capsule is shown being transported from the Baikonour plant to the launch pad

35. Soviet R-7

36. Soviet R-7
A Soyuz launch vehicle and mated Soyuz capsule is shown being transported from the Baikonour plant to the launch site stand

37. Soviet R-7
The original design of the R-7 core and four strap-on booster was adapted as a lunar and interplanetary launcher by adding a third and fourth stage
Later manned launchers also included a third stage to produce the Vostok launch vehicles that had a payload capacity of 5 metric tons

38. Soviet R-7
An even larger third stage was used for the Voskhod and Soyuz crew vehicles, with a payload over 6 tons
A fourth stage was used for the Molniya booster to place communications satellites into high-inclination, high-altitude, eccentric orbits

39. Called the R-7 and R-7A Semyorka
Soviet R-7
R-7 ICBM
Called the R-7 and R-7A Semyorka
Classified by Western intelligence as SS-6 Sapwood
Launch system variants
Sputnik, Polyot, Voskhod, Soyuz/Vostok, Vostok, Luna, Vostok-L · Vostok-K · Vostok-2, Vostok-2M, Molniya, Molniya-M, Soyuz, Soyuz-L, Soyuz-M, Soyuz-U, Soyuz-U2, Soyuz-FG, Soyuz-2

40. References and Resources
Mitchel, Don P., The R-7 Missile

41. The End