Delta IV Heavy launches on debut West Coast launch with NRO L-49
The United Launch Alliance (ULA) Delta IV Heavy has made its first launch from Vandenberg Air Force Base on Thursday. The rocket, launched on schedule from Vandenberg Air Force Base, lifting off at 21:10 UTC, en route to placing a classified payload – L-49 – into orbit for the US National Reconnaissance Office (NRO).
Delta IV-H Launch Overview:
The Delta IV which launched is Delta 352, which appears to have been named “Betty” by its launch crews. It flew in the Heavy configuration; the highest capacity EELV variant and the most powerful unmanned rocket currently in service. The launch was the third Delta IV launch from Vandenberg but the first to use the Heavy configuration. Overall, it was the fifteenth Delta IV launch, and the fifth to use the Heavy configuration.
The Delta IV Heavy consists of a Common Booster Core (CBC) first stage, powered by a single RS-68 engine. Two more CBCs are attached to its sides as boosters. The RS-68 is a cryogenic rocket engine, fuelled by liquid hydrogen with liquid oxygen oxidiser. The launch of Delta 352 will take the flight counts for the CBC and RS-68 to twenty five.
The second stage of the Delta IV is a five metre Delta Cryogenic Second Stage (DCSS). This is powered by a single RL10-B-2 engine, also burning liquid hydrogen and liquid oxygen. The payload is mounted on an adaptor atop the second stage, enclosed in a payload fairing with a diameter of five metres. Two payload fairing are available for Delta IV Heavy launches; a 19.1 metre bisector composite fairing or a 19.8 metre trisector aluminium fairing.
The flight profile for the launch was not entirely clear. No information was published, and a Delta IV Heavy had never launched to Low Earth orbit before. The last two Titan IV launches from Vandenberg, both carrying the same type of spacecraft as is believed to be aboard Delta 352, deployed their satellites less than ten minutes after launch, with a direct insertion into low Earth orbit.
From ULA documentation on the Delta IV, it seems more likely that a two-burn profile would have been used for the launch, with spacecraft separation about an hour and a half after launch.
Early flight milestones were predicted to be probably be the same regardless of the flight profile. Those milestones followed with the three RS-68 engines igniting five and a half seconds before the flight is due to begin. At T-0, Delta 352 will be released, and will begin its ascent towards orbit. About fifty seconds after launch the RS-68 engine of the core stage will begin to throttle down to fifty seven percent in order to conserve fuel. The process of throttling down will last around five seconds.
The vehicle will experience maximum dynamic pressure, or Max-Q, as it approaches the speed of sound about 81 seconds after launch. The pressure will reduce once the vehicle is supersonic.
The strapon CBCs will begin to throttle down about 235 seconds after launch, and seven seconds later their engines will shut down. After another three seconds the boosters will be jettisoned, with the remaining RS-68 throttling back up a second later. At around this point, Delta 352 will cross the Kármán line and enter space.
The payload fairing will separate from around the payload around 277 seconds after launch. The first stage will continue to burn until T+328 seconds, when its engine will cut off. Six seconds later, the first and second stage will separate, and the second stage engine nozzle will begin to deploy. Thirteen seconds after staging, the RL10 will ignite.
Assuming that Delta 352 did follow a two-burn flight profile to low Earth orbit, the first burn of the second stage engine lasted around 728 seconds, followed by a coast phase lasting around seventy one minutes and twenty five seconds. The RL10 would have then restart for a nineteen second burn, raising the velocity of the DCSS and payload by about 60 metres per second. Spacecraft separation would then occur shortly afterwards.
Typically for NRO payloads, publicly available coverage of the mission ended at around the time of fairing separation, and an announcement of a successful launch was made shortly thereafter, even if the launch had not actually been completed by that stage.
Delta 352′s payload is officially classified; however it is widely believed to be a KH-11 “Improved Crystal” electro-optical reconnaissance satellite. The KH-11 first flew in the late 1970s, replacing earlier film-return imaging satellites like the KH-9 Hexagon. Instead of returning images by film, KH-11 satellites transmit them electronically. Four separate generations of KH-11 satellites have been identified, with the later two unofficially referred to as KH-11B or KH-12.
KH-11 satellites are designed to produce high-resolution images, which are then relayed to the ground via Satellite Data System (SDS) spacecraft in molniya and geosynchronous orbits. They are reported to resemble the Hubble Space Telescope. This will be the first KH-11 satellite to launch on anything other than a Titan rocket; previous launches have used the Titan IIID, Titan 34D and both types of Titan IV, all of which flew from Space Launch Complex 4E at Vandenberg.
The KH-11 was the last in a series of “Key Hole” reconnaissance satellites, which began with the KH-1 “Corona” series in 1959. KH-1 to 4 satellites carried panoramic cameras which returned films in Satellite Recovery Vehicles, or SRVs. The KH-5 “Argon” satellites were launched around the same period as the Corona spacecraft, and carried lower-resolution cameras for use in mapping operations. The KH-6 “Lanyard” spacecraft were intended to provide high-resolution images, however following two failed missions and a third which returned poor quality images, the programme was cancelled.
The KH-7 and KH-8 “Gambit” spacecraft were operated between 1963 and 1984. They were high-resolution film return satellites, however many details about the programme are still classified. The KH-9 “Hexagon”, which first flew in 1971, replaced the last Corona satellites. It was capable of operating for up to nine months, although it was still limited by the need to return film capsules to Earth. KH-10 “Dorian” was a manned reconnaissance spacecraft, better known as the Manned Orbiting Laboratory. It was cancelled without any spacecraft having been launched.
The first KH-11 satellite, OPS 5705, was launched by a Titan IIID on 19 December 1976. The first five spacecraft have been identified as Block I satellites, with the last being launched on 17 November 1982. The next three launches were of Block II satellites, and these were followed by four Block III spacecraft. The two most recent launches have been identified as Block IV satellites. Of the fourteen launched, thirteen reached orbit successfully, however the first Block II spacecraft was lost in a launch failure.
The programme appears to have been known by many names, as well as KH-11, and the unofficial KH-11B and KH-12 designations, the names “Crystal”, “Kennan”, “Ikon”. Later blocks have been referred to as “Advanced Kennan” and “Improved Crystal”.
Typically, KH-11 satellites operate in a sun-synchronous low Earth orbit with a perigee of about 200 kilometres, and an apogee of a little over 1000 kilometres. Their orbital inclination is always fairly close to 97.8 degrees. The spacecraft operate in two planes, with launches usually alternating between them. Historically launches have occurred at times around 21:00-21:30 UTC for one orbital plane, and around 18:05 UTC for the other. The launch time suggests that the new satellite will replace USA-161, an ageing spacecraft launched in October 2001.
The last KH-11 launch occurred in 2005, on the final flight of the Titan IVB rocket. The Future Imagery Architecture (FIA) programme was supposed to have developed a new electro-optical reconnaissance satellite to replace KH-11, as well as new radar imaging satellites. NRO L-41, launched last September, has been identified by amateur observers as the first FIA radar spacecraft, however the electro-optical satellites are believed to have been cancelled following problems during procurement, with at least one new KH-11 satellite being ordered as a replacement. At around the time at which this happened, the rocket for the NRO L-41 launch was reported to have changed from the Atlas V 501, the lowest-capacity rocket in the EELV fleet, to the Delta IV Heavy, the highest-capacity system.
In April 2009, it was reported that US President Barack Obama had approved a new electro-optical reconnaissance programme, which is believed to include the procurement of a fifth generation of KH-11 derived satellites. The status of this programme is unclear after it ran into opposition from the Senate Intelligence Committee. Either way, this satellite will not be part of this programme, as the satellites could not have been developed quickly enough to be ready for launch this year.
It has also been reported that the Misty and Enhanced Imaging System stealth imaging satellites were based on the KH-11; these two spacecraft were launched by the Space Shuttle and a Titan IVB respectively.
The mission patch for NRO L-49 shows a phoenix rising out of a fire, with the words “melior diabolus quem scies”, which translate into English as “better the devil you know”, indicating the return to the older system following the failure of the attempt to replace it.
An image of a devil features on the launch patch. The old tradition of giving rockets personal names also appears to have been revived; Delta 352 seems to have been named “Betty”, and the Atlas V that launched from Vandenberg last year was named “Gladys”.
Since the identity of NRO L-49 and a KH-11 satellite has not yet been confirmed, several other types of spacecraft are possible. In the past, heavy-lift Titan rockets have also launched Lacrosse radar imaging satellites from Vandenberg; however with the launch of NRO L-41 last year it would appear that smaller, more modern radar satellites have replaced them.
Satellite Data System communications satellites and NOSS signals intelligence spacecraft were also once launched on heavy-lift rockets from Vandenberg, but these had all been replaced by smaller satellites launched on medium-lift rockets by the early 2000s.
A stealth imaging satellite, either part of or a successor to the Misty and Enhanced Imaging System programmes remains an outside possibility; however the United States is believed to have stopped development of dedicated stealth reconnaissance satellites several years ago.
The name NRO L-49 stands for National Reconnaissance Office Launch 49, indicating that this is the 49th payload in the NRO’s launching programme. These launches are not conducted sequentially, and this will be the twenty ninth launch since the designations were introduced. Once in orbit, the satellite will be assigned a USA designation. USA designations are numbers assigned to most US military and NRO satellites.
Although they are traditionally only assigned to military spacecraft, several other payloads deployed by a Minotaur IV launch last year have also received them; with the University of Michigan’s Radio Auroral Explorer being designated USA-218, NASA’s O/OREOS and FASTSAT spacecraft being designated USA-219 and 220 respectively, and the University of Texas FASTRAC-1 “Sara-Lily” spacecraft becoming USA-222.
Delta 352 launched from Space Launch Complex 6 (SLC-6) at Vandenberg Air Force Base. SLC-6 was built in the late 1960s as a Titan III launch complex in support of the Manned Orbiting Laboratory programme; a US Air Force project to use space stations for reconnaissance and scientific research. Following the cancellation of MOL, SLC-6 was rebuilt as a Space Shuttle launch complex. Following the Challenger accident in January 1986 a review of programme safety led to plans for Shuttle launches from Vandenberg being abandoned.
Following the cancellation of Shuttle missions from SLC-6, rumours spread that the complex had been built on a Native American burial ground, and was subject to a curse; however this has never been substantiated. The complex remained unused until the mid 1990s, when the small Athena rocket began operations from Vandenberg.
After the initial retirement of the Athena in 2001, SLC-6 again fell into disuse. Following the announcement that Athena would be returned to service in the next few years, it is believed that if it needs to launch from Vandenberg it will use the Minotaur launch complex, SLC-8; the Minotaur IV and Athena have very similar first stages.
In the early 21st Century, SLC-6 was rebuilt as a Delta IV Medium launch complex. Support for the Delta IV Heavy was not originally planned, as it was expected that future polar-orbiting reconnaissance satellites would be smaller than previous designs. The first Delta IV launch from SLC-6 occurred in June 2006, carrying USA-184; an Improved Trumpet electronic intelligence satellite. A further launch was conducted later that year with a DMSP weather satellite.
When NRO L-49 was remanifested as a Delta IV Heavy mission, work began on SLC-6 to accommodate the complex. No launches could be conducted whilst this work was ongoing, and the NRO L-25 mission, which had originally been scheduled for late 2007 or early 2008, is now believed to be scheduled for launch next year.
The launch was the first American orbital launch of 2011. Last year, America conducted 15 orbital launches; less than it typically has, allowing China to conduct as many launches as it for the first time. NRO L-49 was the second orbital launch of 2011 overall, following Thursday’s launch of the first Zenit-3F, carrying the Elektro-L No.1 satellite.
Click here for recent Delta IV articles: http://www.nasaspaceflight.com/tag/delta-iv/
The launch of NRO L-49 came amid a period of increased activity in terms of NRO launches. One Medium and one Heavy payload were launched during the last four months of last year, and in the next year two heavy, two medium and one light payload are scheduled to fly. Two NRO CubeSats, QbX-1 and QbX-2, were also launched in December aboard a Falcon 9.
Part of the Colony 1 programme, the satellites were used for technology demonstration missions, and decayed from orbit on 6 and 16 January respectively. Eight more QbX satellites are expected to be launched on a Falcon 1e later this year, along with up to 24 satellites for the US military. The next launch of an NRO payload, NRO L-66, is scheduled for early next month atop a Minotaur I from Vandenberg.
The next Delta IV launch is scheduled for April, when a Delta IV-M+(4,2) will launch the NRO L-27 mission from Cape Canaveral. The next Delta IV Heavy launch is planned for December, also carrying an NRO spacecraft from Cape Canaveral; NRO L-15. In between, another Delta IV-M+(4,2) launch is planned, carrying a Global Positioning Satellite. Three Delta II launches are also planned, including the final flight of the standard 7000 series, and probably the final flight of any Delta II.
United Launch Alliance is also expected to launch five Atlas V rockets this year, starting at the beginning of March with the first flight of the second X-37B; OTV-2. AT the end of the same month, another Atlas V is slated to deploy an NRO payload from Vandenberg.
A launch at the end of April is scheduled to carry the first Space Based Infrared System (SBIRS) satellite. The last two Atlas launches of the year will deploy planetary probes for NASA: in early August it will send the Juno spacecraft on its way to Jupiter, and in late November another flight will deploy the Mars Science Laboratory, or “Curiosity” spacecraft bound for Mars.
(Lead Image via Pat Corkery – ULA)