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

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The Soviet counterpart to the Saturn V, intended as
the launch vehicle for the Soviet Union’s attempt
at a manned landing on the Moon (see Russian
manned lunar programs). The N-1 would have been
the world’s most powerful booster, but it was beset by
technical problems and never made a successful
flight. Work on it began in 1962 under the direction
of Sergei Korolev.
On November 25, 1967, a mockup of the N-1 was
installed on launch pad Number 1 at Baikonur for 17
days of electrical tests. The first flight-ready vehicle
was erected on the same pad on May 7, 1968, but it
had to be returned to the assembly building after
cracks were found in the first-stage structure. After
repairs, it was again set up on the launch pad in
November 1968, only to be replaced with another
mockup for further tests and launch team training.
Finally, in mid-January 1969, N-1 Number 3L was
moved to the pad ready for its first test flight. The test
was a huge gamble since, in a desperate bid to get to
the Moon first, the large cluster of first-stage engines
had never been tested as a group. The payload was
originally to have been an unmanned Lunar Orbiter
Cabin (LOK) and Lunar Cabin (LK) designed to
carry Soviet cosmonauts to a Moon landing. But as
neither the LOK nor the LK were yet ready to fly, the
payload was switched to a modified version of the circumlunar
spacecraft L-1 known as the L-1S. After
four weeks of on-pad preparation, the first N-1 was
ready to go. Hours before the launch, the chief
designer, Valery Mishin, who had taken over the
project after Korolev’s death in 1966, went to the
launch pad while propellants were being loaded and
christened the rocket by breaking a bottle of champagne
against its hull. On February 21, 1969, the N-1
lifted off into clear skies—and trouble. Seconds into
the flight, two of the 30 first-stage NK-33 engines
shut down due to a problem with the KORD control
system that guided the vehicle. The N-1 was designed
to operate with as many as four first-stage engines out
of action, so the flight continued with the other
engines compensating for the loss. At T + 25 seconds
the engines were throttled back as planned as the N-1
passed through the point of maximum dynamic pressure,
and at T + 65 seconds they were throttled back
up to full power. At this point the lack of adequate
N-1
testing of the main engines became apparent. The
engines throttled up more quickly than expected,
causing stronger than planned vibrations. A liquid
oxygen (LOX) pipeline burst and started a fire in the
engine compartment before KORD could shut down
the affected engine. The surrounding engines and
turbopumps quickly overheated and exploded. At
T + 70 seconds, KORD finally shut down all engines,
and the launch escape system was activated. The L-1S
capsule was safely recovered about 35 km downrange,
but the now powerless N-1 slammed into the
Kazhak steppes and exploded some 48 km from its
launch pad.
N-1 FACTS
Length: 105 m
Payload: 95 tons (LEO), 30 tons (Moon)
Number of engines
First stage: 30
Second stage: 8
Third stage: 4
Propellant (all stages): RP-1 and LOX
First stage thrust: 44,100,000 N
In a last-ditch effort to win the Moon race, a second
N-1 was modified and prepared for launch. Following
the successful tests of the American Lunar Module in
Earth orbit during Apollo 9 in March and the test in
lunar orbit by Apollo 10 in May, only a failure of
Apollo 11 and a successful N-1 test would leave the
Soviets with any chance of being the first to land a
man on the Moon. On July 3, the second N-1, Number
5L, took off from pad Number 1 with another
L-1S as its primary payload. What followed was an
even greater disaster than the first. At the very point
of liftoff, debris in the LOX tank was sucked into one
of the first-stage engines, causing its turbopump to
explode. This led to a second engine failure, which in
turn triggered a chain reaction, destroying several
neighboring engines and damaging the KORD control
system. The launch escape system was activated
and carried the L-1S payload to safety. However, the
fully fueled N-1 fell back onto its launch pad just 18
seconds after launch, destroying the rocket and pad
Number 1, heavily damaging pad Number 2, and end-