The Complete Book of Spaceflight: From Apollo 1 to Zero Gravity

It was also built in sections so that it could be easily
shipped to and assembled at its launch site in Woomera,
Australia. Consisting in its first version of a single stage
10.2 m high, 1.8 m in diameter, and weighing 5.4 tons at
takeoff, Black Knight was propelled by an Armstrong-
Siddeley Gamma 201 engine equipped with four swiveling
nozzles that developed 75,000 newtons (N) of thrust
during a burn time of 140 to 145 seconds. Four fins, each
with a span of 1.8 m, provided aerodynamic stabilization,
and two were equipped with small pods containing
tracking equipment. On September 7, 1958, Black Arrow
01 took off from Woomera and reached what was then a
new record altitude of 564 km—an impressive achievement,
considering that the first Soviet and American
satellites, Sputnik 1 and Explorer 1, had already been
launched. Following the cancellation of Blue Streak in
1960, Black Knight’s future seemed in jeopardy. However,
the rocket had proved so successful and costeffective
that it found new life as part of the Gaslight
program, carried out in cooperation with the United
States and Australia. The main objective of this program
was to study the effects of high-speed reentry on dummy
nuclear warheads. It required the development of a twostage
version of Black Knight with the second stage, powered
by a so-called Cuckoo engine (a Skylark booster),
pointing downward. This new variant of Black Knight
stood 11.6 m high and weighed 6.35 tons. Six Gaslight
flights were carried out up to June 1961. In 1962, the tests
continued as part of the Dazzle program, in cooperation
with the United States, Canada, and Australia. In August
1962, a 95,000-N Gamma 301 engine replaced Gamma
201 on the first stage, and eight more flights were conducted
with this more powerful engine. The last of the 22
Black Knight flights took place in November 1965. See
Black Arrow.
black powder
The oldest of explosives, more commonly known today
as gunpowder, though it was first used by the Chinese in
firecrackers and to propel black-powder rockets (see Chinese
fire-rockets) long before guns were invented. Its
ingredients are saltpeter, or potassium nitrate (about
75%), charcoal (about 15%), and sulfur (about 10%).
Knowledge of the explosive spread from China and other
parts of the Far East to the Arab world and then to Western
Europe by the mid-thirteenth century. Its preparation
was described, for example, by Roger Bacon and Albertus
Magnus.
blackout
(1) A fade-out of radio communications due to environmental
factors such as ionospheric disturbances or a
Blue Streak 57
plasma sheath surrounding a reentry vehicle. (2) A condition
in which vision is temporarily obscured by blackness,
accompanied by a dullness of certain other senses,
brought on by decreased blood pressure in the head and
a consequent lack of oxygen. It may occur, for example,
as a result of being exposed to high g-forces in an airplane
or spacecraft (see anti-g suit).
Blagonravov, Anatoli Arkadyevich (1895–1975)
A Soviet academician who helped establish cooperation
in space between the United States and the Soviet
Union. As the Soviet representative to the United
Nations’ Committee on the Peaceful Uses of Outer Space
(COPUOS) in the early 1960s, Blagonravov was a senior
negotiator alongside NASA’s Hugh Dryden for cooperative
space projects at the height of the Cold War. During
World War II, he specialized in infantry and artillery
weapons, and later he worked on the development of
rockets.
bleed-cycle operation
A mode of operation in some liquid rocket engines in
which the turbopump is driven by hot gases bled from
the combustion chamber assembly during main-stage
operation.
blockhouse
A heavily reinforced building, designed to withstand
blast and heat, that contains the electronic controls and
equipment for preparing and launching a rocket.
blowdown
The draining of a rocket engine’s unused liquid propellants.
Blowdown may be done before or after firing the
engine.
blowoff
The separation of a portion of a rocket or spacecraft by
explosive force. The Solid Rocket Boosters of the Space
Shuttle, for example, are separated by blowoff.
Blue Scout Junior
A smaller Air Force version of the Scout launch vehicle
that was used for suborbital military tests.
Blue Streak
A British launch vehicle of the 1950s that started out as
an intercontinental ballistic missile (ICBM) and became
an ancestor of the Ariane. Blue Streak was designed to