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Principal
characteristics of rocket R-7 |
Maximum firing range, km
(not considering the Earth rotation)
Launch mass, t
Warhead mass, t
Mass of filled in propellants (LOX, kerosene,
hydrogen peroxide, gas, etc.), t
Velocity at the moment of PU burn, m/s:
PU ground thrust (of stages 1 and 2), tf
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8000
280
5.3 - 5.5
253
2170
6385
403.4
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The Government Decree of February 13, 1953 obliged to work
out a preliminary design of a two-stage ballistic rocket
170 t in mass with a separable warhead 3000 kg in mass capable
to be launched to a range of 8000 km. In October 1953, the
design assignment was changed: a fire charge mass was increased
to 3000 kg (a total mass of the rocket warhead - to 5500
kg) with a flight range remained unchanged, i. e. the design
had to be modified radically.
In January 1954 the Board of Chief Designers among which
were S. P. Korolev, V. P. Barmin, V. P. Glushko, B. M. Konoplev,
V. I. Kuznetsov, N. A. Pilyugin took place with the participation
of M. I. Borisenko, K. D. Bushuev, S. S. Kryukov, and V.
P. Mishin to discuss further work on the rocket with regard
to increased mass of its warhead. The board made a resolution
to use a standardized engine of a comparatively small size
for all stages, to limit overall dimensions of the stages
to allow their railway transportation. Because of the operation
environment, stationary ground equipment had to be designed
to employ a unique method for the rocket suspension on application
specific deflectable trusses that allowed to keep the rocket
unloaded during stoppage and to reduce its mass.
To achieve the specified firing accuracy, scattering of
engine thrust aftereffect impulse should stay within a strictly
fixed range, however, in the preliminary design phase OKB-456
(V. P. Glushko) did not manage to solve this problem. At
that time it was decided to use steering verniers in the
capacity of control members to generate finite thrust after
the main engine has been shut down and a required aftereffect
impulse. In so far as V. P Glushko refused to develop vernier
thrusters, S. P. Korolev charged M. V. Melnikov to do this
work. The vernier thrusters containing gimbals combined
with fuel delivery lines were sized to a 2.5 tf thrust.
Each strap-on booster contained two and a core stage contained
four vernier thrusters.
In designing the vernier thruster many problems have been
solved and new structures developed. These structures found
application and further evolution.
In February 1954 the rocket development milestones were
agreed to and on May 20, 1954 a Decree enacted development
of two-stage ballistic rocket R-7. In the order of Minister
of Defense it was particularly underlined that the development
of rocket R-7 was a matter of national importance and all
work had to be accomplished within the specified time limits.
The R-7 design was radically distinguished from all previous
rockets by its configuration and structural arrangement,
overall dimensions and mass, propulsion capacity, a number
and purpose of systems, etc. It consisted of four strap-on
boosters attached to a core stage. By their interior arrangement,
both the strap-on boosters and the core stage were similar
to a single-stage rocket design with a front location of
an oxidizer tank. Fuel tanks of all stages also served as
structural elements. Engines of all five stages were ignited
from ground. Each stage accommodated a standardized four-chamber
liquid-propellant engine sized to a 80-90 tf thrust. A control
system incorporated a stabilization automatics ensuring
normal and lateral stabilization, an apparent velocity control
system, and a range and direction radio control system.
On the core stage a fuel tankage simultaneous depletion
system was provided because a lack of this system caused
a large range loss.
In conclusions on the R-7 design it was noted that in the
engineering design phase it will be required to carry out
serious experimental work on the rocket warhead, study and
test engine control systems, verify combustion chambers
with high power characteristics, verify control system hardware,
vernier thrusters, and separation systems.
The R-7 rocket preliminary design was reviewed by a Commission
of Experts headed by Academician M. V. Keldysh. The commission
included prominent scientists and the Customer representatives.
The commission recognized that the submitted preliminary
design could serve as a basis for further work. On November
20, 1954 the preliminary design of rocket R-7 was approved
by the Board of Ministers of the USSR.
Work on rocket R-7, up to its full completion, was split
into three phases:
- Phase 1: the design completion relying on critical
comments of the Commission of Experts, manufacturing of
two lots of rockets for bench tests and one lot of rockets
for flight tests;
- Phase 2: testing of a series of rockets under a complete
program, modifications to the rockets relying on the testing
results;
- Phase 3: manufacturing of a series of rockets with
updated characteristics for flight tests.
In Phase 1, a good deal of difficulties were posed for
testing a vernier thruster.
A theoretical drawing of rocket R-7 was approved by S. P.
Korolev on March 11, 1955 and on July 25, 1956 the updated
preliminary design documentation was signed. Development
of design documentation on rocket R-7 started as early as
in 1953.
In 1956 two sets of stage A (a core stage) and two sets
of stage B (one of the strap-on boosters) have been manufactured
for bench tests and three mockups - for ground tests. In
parallel, the first flight prototype has been made late
in 1956 and delivered to the launch site.
In the second half of 1956, it was decided to involve the
Kuibyshev plant "Progress" in the rocket R-7 mass production.
At the plant the first rockets were assembled of parts and
units made at Plant 88. Further, the third branch office
of OKB-1 headed by the deputy Chief Designer D. I. Kozlov
was set up at the "Progress" plant. To this branch office
reformed in 1974 into an independent organization - the
Central Specialized Design Office - technical documentation
on rocket R-7 and its modifications was passed on by our
enterprise to start mass production at the "Progress" plant.
The rocket design novelty, new approaches to a launch pad
structure required a large amount of experimental development
of certain systems and the rocket as a whole. For this purpose
an integrated test program has been worked out and implemented.
- Tests of rocket-7 radio control system on a basis of
rocket R-5R. From May 31 to June 15, 1956 three successful
launches of Rocket R-5R have been implemented.
- Flight tests of the R-7 control systems: the core stage
fuel tankage simultaneous depletion system, the apparent
velocity control system, the normal and lateral stabilization
system, the telemetry system. In a period from February
16 to August 18, 1956, ten launches of rocket M5RD have
been carried out.
- Tests of shockless ejection of the rocket out of the
launch pad at the Leningrad Metallic Plant. The tests
were run on the R-7 mockup яN that allowed to fill the
tanks with distilled water containing anticorrosive agent.
- Firing tests of the rocket stages and the integrated
rocket in a period from July 1956 to March 1957 on 2 NII-88
testing facility.
- Tests of the launch pad service tower and verification
of its mating with aft compartments of the rocket stages.
The work was carried out at 2 NII-88.
- Tests of the rocket strap-on boosters separation system
on a dedicated setup at 2 NII-88.
- Verification of the rocket pre-launch processing technology
and interaction between the launch site services.
In March 1957 the first rocket R-7 № M1-5 has been delivered
to the pre-launch processing facilities for flight tests.
Rocket R-7
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Launch of rocket R-7
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On April 10, 1957 the first meeting of the State Commission
chaired by V. M. Ryabkov (a Chairman of the Military-Production
Complex) took place to decide on flight tests. S. P. Korolev
(a technical manager). Results of the R-7 experimental development
and processing for flight tests were reported by S. P. Korolev.
On May 5, 1957 rocket R-7 № M1-5 has been delivered to the
launch site.
The first launch has been carried out on May 15, 1957, at
19:01 Moscow time. Visually, the flight seemed to run normally,
but then, changes in the engine exhaust gas flame of the
aft compartment became apparent. Processed telemetry showed
that strap-on booster D fell off at the 98-th second and
the rocket lost stability. The accident cause turned to
be leakage of its fuel line. This launch have permitted
to obtain test data on the lift-off and stage 1 flight dynamics.
The second launch planned for June 11, 1957 failed despite
of three trials: in the first two trials, because of freezing
of the main oxygen valve disc in strap-on booster B, the
launch sequence was reset; the third trial failed because
of the propulsion emergency shutdown in the preliminary
thrust stage mode caused by an error made when installing
a nitrogen purging valve of the core stage oxygen line.
The rocket was dismounted from the launch pad and returned
to the processing facility.
The third launch took place on July 12, 1957. At 33s the
rocket lost stability. The accident resulted from a closure
on the shell of the integrating device control signal circuits
via a roll channel.
The forth launch of rocket R-7 carried out on August 21,
1957 was successful and the rocket reached its destination
point for the first time. The main drawback of this launch
was a destruction of the warhead in atmosphere in the trajectory
descent leg. On August 27, 1957, the TASS report was published
on the intercontinental ballistic rocket tests.
The next launch of rocket R-7 carried out on September 7,
1957 mainly verified the previous launch results.
Positive results of rocket R-7 flight in the ascent phase
of trajectory justified its use for launching the first
two artificial Earth's satellites (of the Pя type). Rockets
№ 1Pя and №2Pя were used in the capacity of launchers modified
with the consideration of flight test results and specified
tasks.
Relying on results of six launches of rocket R-7, its warhead
was replaced with a new one, the separation system was modified,
and slot antennas of the telemetry system were used.
A launch of rocket R-4 was successful for the first time
on March 29, 1958 (the warhead reached the target without
destruction). Flight tests of the second cycle have been
completed with launches of rockets R-7 on May 24 and July
10, 1958.
The third cycle of flight tests have been carried out from
December 24, 1958 to November 27, 1959. 16 rockets have
been launched of which 8 were made at the Progress mass
production plant. On rockets of the third version the inter-tank
instrumentation compartment was removed from the core stage
(instruments were accommodated in a single section of the
core stage nose), vernier thrusters of higher capacity and
improved power supply system were introduced among other
modifications.
In parallel with the flight tests, space launch vehicles
based on rockets R-7 of the third version were being launched
(September 1958 - November 1959). Seven automatic space
stations have been launched.
On January 20, 1960 intercontinental ballistic rocket R-7
entered service.
From December 24, 1959 flight tests of rocket R-7A without
a radio control system and with a newly designed warhead
were commenced. Rocket R-7, with a launch mass of 276 t
and a warhead mass of 3 t, was capable to fly to a range
of 12 000 km. During flight tests eight rockets have been
tested of which seven rockets implemented their task.
Rocket R-7A entered service and replaced rocket R-7.
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