|Space Launch Report: Zenit Data Sheet|
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The Zenit (Zenith) rocket was the last, and most advanced, space launch vehicle developed by the former Soviet Union. Although it began life as a military satellite launcher, its primary use in recent years has been to boost commercial satellites into space for the multi-national Sea Launch venture.
Zenit development was begun by Dnepropetrovsk, Urkraine-based NPO
Yuzhnoe during the 1970s as an effort to replace ICBM-based boosters with a purpose-built
space launcher. Early plans called for a modular series of light, medium, and heavy-lift
vehicles, but only the 11K77 medium version won approval. On March 16, 1976, the Central
Committee of the Soviet Union officially approved development of the 11K77 two-stage
Zenit-2, a rocket capable of boosting 13.7 metric tons into low earth orbit (LEO) from
Baikonur, as a replacement for the Tsyklon booster then in use. Subsequently, Zenit-2 won
the job of launching the USSR's new Tselina-2 electronic intelligence satellites while the
Zenit-2 first stage was selected to serve as a strap-on booster for the Energia heavy-lift
launcher. Initial planning called for the first Zenit-2 launch to occur in 1982.
Development of Zenit's powerful staged-combustion cycle first stage engine by the Glushko design bureau (later called Energomash) soon ran into trouble, however. The four-chamber, single-turbopump kerosene/liquid oxygen (LOX) engine, identified as RD-170 for Energia and RD-171 for Zenit-2, suffered a series of test failures during 1981-83 that threatened both programs. The development challenge was daunting. RD-170/RD-171 was the most powerful liquid propellant rocket engine ever developed, producing more thrust than the Saturn V F-1 (806 tons versus 789 tons) and operating at higher chamber pressures than NASA's Space Shuttle Main Engine (245 bar versus 204 bar). Eventually, Glushko was able to qualify the powerful engine for flight.
The rocket's first stage consisted of an engine compartment topped by a kerosene tank and, on top of both, a LOX tank. The tanks shared a common bulkhead. All four RD-171 chambers gimballed to provide three-axis control.
The second stage used a single fixed RD-0120 main engine
augmented by the four gimballed thrust chambers of an RD-8 vernier engine. A toriodial
kerosene tank wrapped around the RD-0120 engine. A separate cylindrical LOX tank was
positioned above the engine section. The launch vehicle control system was mounted atop
the second stage.
A new launch complex, named Area 45, was constructed on Baikonur's eastern flank. The pad site allowed "automatic" launch processing, with the horizontally integrated launch vehicle transported to and erected on the "launch starter" pad only 90 minutes before liftoff. The process included automatic connection of propellant, power, and data lines. Area 45 included two pads. The "left" pad hosted all initial launches and is still in use. The "right" pad entered service in May 1990, but it was destroyed by an on-pad explosion during its second use in October of that year.
On April 13, 1985, the first 57 meter tall, 460 ton Zenit-2 lifted off from the "left" pad at Baikonur Area 45 with a dummy payload representing a Tselina-2 satellite. The first stage performed well, but problems with the second stage propellant controller caused the RD-0120 second stage engine to run out of fuel and shut down a few seconds early, leaving the vehicle short of orbital velocity. Another second stage problem doomed the second launch on June 21, 1985. Finally, on October 22, 1985, the third Zenit-2 successfully reached orbit with a dummy payload that was announced as Kosmos-1697. Eight more Zenit-2 launches were performed before the vehicle was declared operational at the end of 1987.
Within a few years, however, the collapse of the Soviet Union, the end of the Energia/Buran program, and the technical challenges offered by the new rocket contributed to a series of failures. On October 4, 1990, the 15th Zenit-2 failed five seconds after the liftoff from Area 45 "right" launch complex. The 460 ton rocket fell back through the pad into the flame trench and exploded, obliterating the massive concrete launch pad. The next two Zenit-2 launches, in 1990 and early 1991, fell short of orbit when their second stages failed. After a series of successes, another Zenit-2 failed 48 seconds after liftoff on May 20, 1997.
Zenit returned to service with two successful government launches in 1998, but the rocket suffered an embarrassing failure on September 9, 1998. During its first international commercial satellite launch attempt with 12 Globalstar satellites, the rocket suffered a control system failure during the second stage burn. Globalstar had planned to buy multiple Zenit-2 launches, but after the failure the company switched to Boeing Delta II and Starsem Soyuz. The failure, combined with Russia's gradual ending of Zenit-2 military launches, dealt a serious blow to the rocket. Only four Zenit-2 launches occurred between 1999 and 2001, and none took place in 2002.
Zenit managed an
unlikely rebirth, however. During the early 1990s, several companies began studying the
creation of a three-stage "Zenit-3" to launch commercial satellites into
geosynchronous transfer orbit (GTO) from a floating launch platform. Payload mass could be
increased by launching from the equator, where the Earth's rotation provides more velocity
to assist the launcher. Russia's RKK Energia offered its Blok DM as an upper stage, USA's
Boeing its payload integration and western marketing skills, Norway's Anglo-Norwegian
Kverner Group the floating launch platform and command ship, and SDO Yuzhnoye/PO Yuzhmash
the two-stage Zenit, launcher equipment, and launch operations. The four companies
officially formed Sea Launch in 1995 with 25%, 40%, 20%, and 15% shares, respectfully.
Plans called for Sea Launch operations to be based in Long Beach, California, near several
major satellite manufacturers.
For Sea Launch, Zenit's first stage was strengthened, the second stage engine thrust was increased, more propellants were loaded, and electronics were upgraded. The improved rocket, named Zenit-3SL, was topped by the Blok DMSL third stage and an enlarged payload fairing. Initially rated to handle 5.25 metric ton payloads to GTO, Zenit-3SL's payload capacity soon grew to 6 tons.
Hughes signed on as the first Sea Launch customer in 1995, adding three orders in 1996. Space Systems/Loral ordered five launches in 1996.
In late 1996, the "Sea Launch Commander" was launched
from the Kyaerner shipyard in Scotland. Both "Commander" and launch platform
"Odyssey" sailed to Russia in 1997 for outfitting. On June 12, 1998,
"Commander" departed St. Petersburg, Russia for Long Beach, carrying the first
two Sea Launch vehicles. Eight days later "Odyssey" left Russia for Long Beach,
making an epic journey through the Dardenelles Straight.
After weathering a 1998 suspension of work order from the U.S. government due to technology transfer concerns, Sea Launch Zenit successfully performed its first launch with a dummy payload on March 27, 1999. On October 9, 1999, the second Zenit 3SL successfully boosted Direct TV 1-R into GTO.
On March 12, 2000, Sea Launch suffered its first launch failure. The ICO F-1 communications satellite was lost after the rocket's second stage shut down 80 seconds early. A control pressure valve commanding error in the pre-launch ground sequence software was responsible. The improper valve setting caused control of the second stage RD-8 vernier engines to be lost after some time passed, so that the stage tumbled out of control. The rocket's control system automatically shut down the RD-0120 engine when it lost control authority.
Sea Launch recovered with eight consecutive successful launches,
but the 14th flight failed in mid-2004 when the DMSL stage shut down 54 sec early due a
suspected loose electrical connection. The Apstar 5 payload was left in a transfer orbit
with an apogee 14,000 km lower than planned, but the satellite was subsequently able to
use its own fuel to reach the planned geosynchronous orbit.
Zenit 3SL then reeled off nine consecutive successes, including five in 2006. Spaceway 1, orbited during that string, was, at 6.1 tonnes, the heaviest commercial GTO payload launched up to that time. But the run ended emphatically on January 30, 2007 when a Sea Launch Zenit with SES New Sky's NSS-8 satellite exploded in a huge fireball at liftoff. The failure, caused by the ingestion of a metal object by the RD-171M main engine's LOX turbopump, knocked off and sank Odyssey's 250 tonne exhaust deflector and damaged other parts of the platform and its launch equipment. While Sea Launch scrambled to repair Odyssey, several payloads drifted away to Ariane or Proton.
Sea Launch was ready to return to flight during the final weeks
of 2007, but poor weather conditions at the launch site forced Odyssey to return to port.
Zenit 3SL finally returned to service on January 15, 2008 with the successful launch
While Sea Launch battled its way back from the 2007 failure, a Zenit renaissance was being planned for Baikonur, where "Land Launch" Zenit flights were scheduled. Zenit 2 SLB and Zenit 3 SLB variants would carry commercial payloads from Baikonur's remaining 45/1 pad. On June 29, 2007, a Zenit 2M, equipped with the RD-171M and upgraded digital flight control computer that the new Land Launch Zenit's would use, flew successfully from Baikonur.
The first Zenit 3 SLB, a two-stage Zenit topped by an RSC Energia Blok DM-SLB third stage, arrived at Baikonur for pre launch processing in late 2007. On April 28, 2008, the rocket carried Amos 3, an Israeli communication satellite, into near geosynchronous orbit from Area 45, Pad 1.
Sea Launch Bankruptcy
On June 24, 2009, about three months and 10 years after it
performed its first demonstration space launch from a platform floating in the Pacific
Ocean, Sea Launch Company filed for Chapter 11 bankruptcy court protection. The unique
international consortium, owned by Boeing (40 %), Russia's RSC-Energia (25 %), Aker ASA of
Oslo, Norway (20 %), and Ukraine's SDO Yuzhnoye/PO Yuzhmash (15%) listed assets of
$0.1-0.5 billion and liabilities of $0.5-$1 billion. Boeing said that it might have
to charge as much as $0.513 billion against earnings as a result of the bankruptcy. Sea
Launch reportedly owed Boeing $0.978 billion in loans, trade debt, and partner
It was the first time that a major, established launch services
company had declared bankruptcy. Other companies, like Kistler, failed prior to
establishing service. For that reason, it was difficult to predict whether Sea
Launch would emerge as a continuing business. The partners, especially Boeing, were
likely in position to decide whether or not the business continued.
On January 20, 2011, the first Zenit 3F (or Zenit 3SLBF) was used
to orbit Russia's first Electro-L weather satellite from Baikonur. Zenit 3F used an
upgraded hypergolic Fregat SB upper stage in place of Energia's cryogenic Blok DMSLB
stage. Fregat SB added drop tanks to the previously-flown Fregat stage.
* Throttles to 50% at 114 sec
DATE VEHICLE ID PAYLOAD MASS(t) SITE* ORBIT* ------------------------------------------------------------------------------------- 04/13/85 Zenit-2 1L Dummy 3.25 TB 45/1 [FTO] 06/21/85 Zenit-2 2L Dummy 3.25 TB 45/1 [FTO] 10/22/85 Zenit-2 Dummy 3.25 TB 45/1 LEO [2a] 12/28/85 Zenit-2 5L Tselina-2 3 3.25 TB 45/1 [EEO] 07/30/86 Zenit-2 Dummy 3.25 TB 45/1 LEO 10/22/86 Zenit-2 Taifun-1 9/Dummy 3.25 TB 45/1 LEO 02/14/87 Zenit-2 Dummy 3.25 TB 45/1 LEO 03/18/87 Zenit-2 Dummy 3.25 TB 45/1 LEO 05/13/87 Zenit-2 Tselina-2 4 3.25 TB 45/1 LEO 08/01/87 Zenit-2 11L Dummy 3.25 TB 45/1 LEO 08/28/87 Zenit-2 10L Dummy 3.25 TB 45/1 LEO 05/15/88 Zenit-2 Tselina-2 5 3.25 TB 45/1 LEO 11/23/88 Zenit-2 Tselina-2 6 3.25 TB 45/1 LEO 05/22/90 Zenit-2 Tselina-2 7 3.25 TB 45/2 LEO 10/04/90 Zenit-2 15L Tselina-2 8 3.25 TB 45/2 [FTO] 08/30/91 Zenit-2 16L Tselina-2 9 3.25 TB 45/1 [FTO] 02/05/92 Zenit-2 Tselina-2 10 3.25 TB 45/1 [FTO] 11/17/92 Zenit-2 Tselina-2 11 3.25 TB 45/1 LEO 12/25/92 Zenit-2 Tselina-2 12 3.25 TB 45/1 LEO 03/26/93 Zenit-2 Tselina-2 13 3.25 TB 45/1 LEO 09/16/93 Zenit-2 Tselina-2 14 3.25 TB 45/1 LEO 04/23/94 Zenit-2 Tselina-2 15 3.25 TB 45/1 LEO 08/26/94 Zenit-2 Orlets-2 1 10.50 TB 45/1 LEO 11/04/94 Zenit-2 Resurs-O1 3 & Safir-R 1.955 TB 45/1 LEO/S 11/24/94 Zenit-2 Tselina-2 16 3.25 TB 45/1 LEO 10/31/95 Zenit-2 Tselina-2 17 3.25 TB 45/1 LEO 09/04/97 Zenit-2 Tselina-2 18 3.25 TB 45/1 LEO 05/20/97 Zenit-2 Tselina-2 19 3.25 TB 45/1 [FTO] 07/10/98 Zenit-2 Resurs-1 2/microsats 2.00 TB 45L LEO/S 07/28/98 Zenit-2 Tselina-2 20 3.25 TB 45L LEO 09/09/98 Zenit-2 22L Globalstar 12 sats 5.40 TB 45L [FTO] 03/28/99 Zenit-3SL/DMSL SL1 DemoSat [HS-702 sim] 4.50 PO OLP GTO 07/17/99 Zenit-2 17L Okean-O 1 6.15 TB 45/1 LEO/S 10/10/99 Zenit-3SL/DMSL SL2 Direct TV 1-R 3.446 PO OLP GTO+ 02/03/00 Zenit 2 1-94 Tselina-2 21 3.25 TB 45 LEO 03/12/00 Zenit 3SL/DMSL SL3 ICO F1 2.75 PO OLP [FTO] 07/28/00 Zenit 3SL/DMSL SL4 PanAmSat 9 3.659 PO OLP GTO 09/25/00 Zenit 2 Orlets-2 2 10.50 TB 45 LEO 10/21/00 Zenit 3SL/DMSL SL5 Thuraya 1 5.108 PO OLP GTO 03/18/01 Zenit 3SL/DMSL SL6 XM-2 "Rock" 4.682 PO OLP GTO 05/08/01 Zenit 3SL/DMSL SL7 XM-1 "Roll" 4.682 PO OLP GTO 12/10/01 Zenit 2 19L Meteor 3M-N1/microsats 2.68 TB LC45 LEO/S 06/15/02 Zenit 3SL/DMSL SL8 Galaxy 3C 4.81 PO OLP GTO+ 06/10/03 Zenit 3SL/DMSL SL16 Thuraya 2 5.177 PO OLP GTO 08/08/03 Zenit 3SL SL10 Echostar 9 4.737 PO OLP GTO 10/01/03 Zenit 3SL/DMSL SL13 Galxy13/Horzns 1 4.090 PO OLP GTO 01/11/04 Zenit 3SL/DMSL SL12 Estrela Do Sul 1 4.8 PO OLP GTO 05/04/04 Zenit 3SL/DMSL SL14 DirectTV-7S 5.5 PO OLP GTO 06/10/04 Zenit 2 1-95 Tselina-2 22 3.25 TB 45/1 LEO 06/29/04 Zenit 3SL/DMSL SL11 Apstar 5 4.6 PO OLP [EEO] 03/01/05 Zenit 3SL/DMSL SL17 XM-3 5.5 PO OLP GTO 04/26/05 Zenit 3SL/DMSL SL18 Spaceway 1 6.1 PO OLP GTO  06/23/05 Zenit 3SL/DMSL SL4 Intelsat Americas 8 5.5 PO OLP GTO 11/08/05 Zenit 3SL/DMSL SL19 Inmarsat-4F2 6.0 PO OLP GTO 02/15/06 Zenit 3SL/DMSL SL15 Echostar X 4.33 PO OLP GTO 04/12/06 Zenit 3SL/DMSL SL21 JCSAT 9 4.4 PO OLP GTO 06/18/06 Zenit 3SL/DMSL SL20 Galaxy 16 4.64 PO OLP GTO 08/22/06 Zenit 3SL/DMSL SL23 Koreasat 5 4.47 PO OLP GTO 10/30/06 Zenit 3SL/DMSL SL22 XM-4 5.193 PO OLP GTO 01/30/07 Zenit 3SL/DMSL SL24 NSS-8 5.92 PO OLP [FTO] 06/29/07 Zenit 2M 1-05 Tselina 2 23 3.25 TB 45/1 LEO 01/15/08 Zenit 3SL/DMSL SL25 Thuraya 3 5.17 PO OLP GTO 03/19/08 Zenit 3SL/DMSL SL26 DirecTV 11 5.92 PO OLP GTO 04/28/08 Zenit 3SLB/DMSLB 1L Amos 3 1.25 TB 45/1 [GEO-] 05/21/08 Zenit 3SL/DMSL SL27 Galaxy 18 4.642 PO OLP GTO 07/16/08 Zenit 3SL/DMSL SL28 EchoStar 11 5.511 PO OLP GTO 09/24/08 Zenit 3SL/DMSL SL29 Galaxy 19 4.69 PO OLP GTO+ 02/26/09 Zenit 3SLB/DMSLB 2L Telstar 11N 4.012 TB 45/1 GTO+ 04/20/09 Zenit 3SL/DMSL SL30 Sircal 1B 3.08 PO OLP GTO+ 06/21/09 Zenit 3SLB/DMSLB 3L Measat 3a 2.37 TB 45/1 GTO+ 11/30/09 Zenit 3SLB/DMSLB 4L Intelsat 15 2.484 TB 45/1 GTO+ 01/20/11 Zenit 3F/FregatSB 1-07/1 Electro-L 1.74 TB 45/1 GEO 07/18/11 Zenit 3F/FregatSB Z2F02 Spektr-R 3.66 TB 45/1 EEO 09/24/11 Zenit 3SL/DM-SL SL39? Atlantic Bird 7 4.60 PO OLP GTO+ 10/05/11 Zenit 3SLB/DMSLB 5L Intelsat 18 3.2 TB 45/1 GTO+ 11/08/11 Zenit 2SB Phobos-Grunt 13.15 TB 45/1 LEO  06/01/12 Zenit 3SL/DMSL SL45 Intelsat 19 5.6 PO OLP GTO 08/19/12 Zenit 3SL/DMSL SL49 Intelsat 21 5.982 PO OLP GTO 12/03/12 Zenit 3SL/DMSL SL50 Eutelsat 70B 5.25 PO OLP GTO 02/01/13 Zenit 3SL/DMSL SL48 Intelsat 27 6.215 PO OLP [FTO] 08/31/13 Zenit 3SLB/DMSLB 6L Amos 4 3.5 TB 45/1 GTO ------------------------------------------------------------------------------------- NOTES:  First Zenit-2 rocket suffered second stage propellant utilization controller failure. Propellant depleted early at T+400 seconds. Failed to orbit. Carried Tselina-2 mass simulator.  Zenit-2 second stage shot down prematurely, again due to propellant control problems. Failed to orbit mass simulator, though some fragments reached orbit. [2a] First Zenit-2 success. Tselina-2 orbit requires plane change to 71 deg from 63 deg, which limits payload mass.  Second stage failure left Tselina-2 in 161 x 826 km x 71 deg orbit. Planned 800 km circular orbit.  First stage engine failure T+4 seconds. Destroyed Area 45 Pad 2.  Second stage failure.  Second stage failure.  Exploded T+48 seconds.  First Zenit commercial launch, failed to orbit - guidance failure at T+272s during second stage flight before fairing separation. planned 1410 km × 1410 km, 52 deg orbit  Zenit 2nd stg control loss T+7 min due to an improper ground connector disconnect. Panned MEO 10390 km × 10390 km x 45 deg.  Second burn of third stage cut off 54 seconds early due to an electrical failure. Left short of planned transfer orbit.  Heaviest Commercial Satellite. First successful 2-burn DMSL profile.  RD-171 engine failed at liftoff due to turbopump ingesting foreign object. Explosion enveloped and damaged LP Odyssey. Planned GTO.  Amos-3 in 34,225 x 39,368 km x 0.72 deg orbit, expected 35,786 x 39,092 km x 0 deg. Shortfall of roughly 75 m/s reportedly cost Amos-3 2-3 years of 18 year design life. Problem caused by "programming error".  Phobos-Grunt Fregat-based propulsion system did not fire, stranding PL in LEO.  RD-171M engine emergency cut off at 23 seconds. Veered off course prior to cut off. Cause was failure of hydraulic pump for thrust vectoring of engine nozzles. List does not include 1/8/2001 Zenit-3SL launch abort just before planned liftoff. Abort call occurred after propellant flow "irreversible operation" into RD-171 engine but before engine ignition. Ships had to return to San Diego for first stage replacement. Stage involved was later refurbished. *Abbreviations: [FTO]: Failed to Orbit [EEO]: Unintended Eliptical Earth Orbit [GTO]: Unintended Geosynchronous Transfer Orbit [LEO]: Unintended Low Earth Orbit TB: (Tyuratam) Baikonur PO: Pacific Ocean OLP: Odyssey Launch Platform References
Sea Launch Payload Planners Guide, Rev. C, Sea Launch, Jan
Last Update: February 16, 2014