The Luna 8K72 vehicles were carrier rockets used by the Soviet Union for nine space probe launch attempts in the Luna programme between 23 September 1958 and 16 April 1960.[1] Like many other Soviet launchers of that era, the Luna 8K72 vehicles were derived from the R-7 Semyorka design, part of the R-7 (rocket family), which was also the basis for the Vostok and modern Soyuz rocket.

Luna 8K72
Blok E upper stage, with Luna payload
FunctionCarrier rocket
ManufacturerRKK Energia
Country of originSoviet Union
Size
Mass277,000 kg (611,000 lb)
Stages3
Capacity
Payload to LEO
Mass4,000 kilograms (8,800 lb)
Associated rockets
FamilyR-7
Launch history
StatusRetired
Launch sitesBaikonur: LC-1/5
Total launches9
Success(es)3
Type of passengers/cargoLuna probes
First stage (Block B, V, G, D)
Powered by1 RD-107-8D74-1958
Maximum thrust990.00 kN
Burn time120 seconds
PropellantKerosene/LOX
Second stage (Block A)
Powered by1 RD-108-8D75-1958
Maximum thrust936.500 kN
Burn time320 seconds
PropellantRP-1/LOX
Third stage (Block E)
Powered by1 RD-0105
Maximum thrust49.0 kN
Burn time316 seconds
PropellantKerosene/LOX

Launches edit

Luna 8K72 was launched nine times from Baikonur LC-1/5:[2]

Launch Date Serial No. LS Payload Result
23.09.1958 B1-3 Ba LC-1/5 Luna E-1 No.1 Failure
11.10.1958 B1-4 Ba LC-1/5 Luna E-1 No.2 Failure
04.12.1958 B1-5 Ba LC-1/5 Luna E-1 No.3 Failure
02.01.1959 B1-6 Ba LC-1/5 Luna 1 Success
18.06.1959 I1-7 Ba LC-1/5 Luna E-1A No.1 Failure
12.09.1959 I1-7B Ba LC-1/5 Luna 2 Success
04.10.1959 I1-8 Ba LC-1/5 Luna 3 Success
15.04.1960 L1-9 Ba LC-1/5 Luna E-3 No.1 Partial Success
16.04.1960 L1-9A Ba LC-1/5 Luna E-3 No.2 Failure

The first flight of a Luna 8K72 (September 1958), which was to launch the Luna E-1 No.1 probe, ended 92 seconds after launch when the rocket broke up from longitudinal ("pogo") oscillations, causing the strap-ons to separate from the vehicle, which then crashed downrange.[3]

The second flight of a Luna 8K72 (October 1958), which was to launch the Luna E-1 No.2 probe, ended 104 seconds after launch when the rocket again disintegrated from vibration.

The third flight of a Luna 8K72 (December 1958), which was to launch the Luna E-1 No.3 probe, ended 245 seconds after launch when the Blok A core stage shut down from loss of engine lubricant.

The resonant vibration problem suffered by the 8K72 booster was the cause of a major argument between the Korolev and Glushko design bureaus. It was believed that the vibrations developed as a consequence of adding the Blok E upper stage to the R-7, shifting its center of mass.

The first probe launched by a Luna 8K72 to reach orbit was Luna 1, launched on 2 January 1959, which was intended as a lunar impactor mission.[4] Luna 1 instead passed within 5,995 kilometres (3,725 mi) of the Moon's surface 4 January 1959, and then went into orbit around the Sun between the orbits of Earth and Mars.[5]

The fifth flight of a Luna 8K72 (18 June 1959), which was to launch the Luna E-1A No.1 probe, ended 153 seconds after launch due to a guidance malfunction of the Blok A core stage, leading to engine shutdown.[6]

Luna 2 was launched by a Luna 8K72 on 12 September 1959. It was the first spacecraft to impact the lunar surface.

The final successful launch of a Luna 8K72 took place on 4 October 1959. The Luna 3 spacecraft took the first photographs of the far side of the Moon.

The eighth flight of a Luna 8K72 (March 1960), which was to launch the Luna E-3 No.1 probe, ended 435 seconds after launch when the Blok E upper stage developed insufficient thrust, causing the Luna probe to reenter the atmosphere and burn up.

The ninth flight of a Luna 8K72 (April 1960), which was to launch the Luna E-3 No.2 probe, failed when the Blok G strap-on booster developed only 75% thrust at liftoff, breaking away from the launch vehicle, which then disintegrated, the strap-ons flying in random directions and exploding as they impacted the ground. The Blok A core stage then crashed into a salt lake.

References edit

  1. ^ "Soyuz - Version: Luna 8K72". Encyclopedia Astronautica. Archived from the original on 2010-01-07.
  2. ^ "Vostok-L (8K72)". Gunter's Space Page. Retrieved 2023-10-22.
  3. ^ "Tentatively Identified Missions and Launch Failures". NASA NSSDC. 2005-01-06.
  4. ^ "Soyuz - Soyuz Chronology". Encyclopedia Astronautica. Archived from the original on 2010-01-07.
  5. ^ "Luna 1 - NSSDC ID: 1959-012A". NASA.
  6. ^ Reichl, Eugen (2017). Moskaus Mondprogramm. Paul Pietsch Verlage GmbH & Co (1. Auflage ed.). Stuttgart. ISBN 978-3-613-04027-4. OCLC 987572365.{{cite book}}: CS1 maint: location missing publisher (link)