This morning noticed the tip of an period for United Launch Alliance (ULA). At daybreak, the protection contractor’s Atlas V rocket launched its ultimate nationwide safety mission for america Area Pressure (USSF). USSF-51 positioned a categorised satellite tv for pc into an undisclosed orbit. It was the 58th and ultimate nationwide safety mission for the Atlas V, the last word member of a household of rockets which has served america for the reason that daybreak of the Area Age. Whereas the Atlas will proceed launching Starliner crew capsules and Amazon Kuiper satellites by means of the tip of the last decade, the navy is transitioning all of its payloads to a brand new technology of launchers.
USSF-51 was not initially alleged to fly on an Atlas V. The Area Pressure awarded the contract to ULA, a three way partnership between Boeing and Lockheed Martin, in 2020 as its first mission underneath the Nationwide Safety Area Launch (NSSL) Part 2 program. The corporate meant to launch the satellite tv for pc on its next-generation Vulcan rocket. Nevertheless, the mission shifted to an Atlas V in 2021, largely on account of delays within the growth of the BE-4 fundamental engines which Blue Origin is constructing for Vulcan [1]. This determination in the end led to a fittingly spectacular sendoff for the ultimate navy Atlas V.
At present’s launch utilized the “551” configuration of the Atlas V. This variant of the rocket, nicknamed “The Bruiser” by ULA CEO Tory Bruno, is probably the most highly effective Atlas V in service. It options 5 strap-on stable rocket boosters to maximise thrust at liftoff, a fairing with a five-meter diameter to accommodate giant payloads, and a Centaur higher stage with a single engine. Meeting of the rocket started on July third when ULA groups secured the bronze-colored Atlas booster onto its cell launch platform. The 5 smaller facet boosters had been then bolted into place, adopted by the Centaur and the already-encapsulated categorised satellite tv for pc. The flight-ready rocket was rolled out to Area Launch Advanced 41, the house of 4 generations of Boeing, Lockheed, and ULA rockets, on July twenty seventh.
The Area Pressure’s ultimate Atlas V mission started lower than half an hour after dawn. At 6:45 AM, the rocket ignited its two RD-180 fundamental engines. Two seconds later, the 5 strap-on boosters concurrently ignited, offering the thrust required to elevate the rocket off the launch pad. The mushy gentle and stark shadows of “golden hour” produced a gorgeous sight for the Area Coast residents who witnessed the launch. Virtually instantly, the Atlas V started pitching downrange to speed up in direction of orbit. The rocket quickly accelerated underneath the thrust of the 5 boosters, leaving an intensive plume of exhaust in its wake.
Simply 35 seconds after liftoff, USSF-51 handed by means of Mach 1. One minute and 45 seconds after liftoff, the boosters depleted the final of their gasoline and had been jettisoned, tumbling away from the remainder of the rocket. Simply over three minutes after the Atlas V departed from SLC-41, the payload fairing adopted go well with. The following milestone within the flight was scheduled to be the separation of the primary stage. Nevertheless, ULA terminated its broadcast in the mean time of fairing separation with a view to defend the identification of the Area Pressure’s payload. The timing of the milestones for the rest of the mission, together with the variety of burns which the Centaur will conduct and their durations, are categorised with a view to maximize the tactical benefit which USSF-51 will present for navy servicemembers.
The exact identification of USSF-51 is a closely-kept secret. Some retailers wrote that the satellite tv for pc was certain for geosynchronous orbit [e.g. 2]. It is a fashionable vacation spot for navy spacecraft, because it permits them to face vigil over a single level on Earth; leveraging Centaur’s 8-hour endurance to position satellites immediately into these orbits is considered one of ULA’s specialties. Nevertheless, even this has not been confirmed by ULA or the Division of Protection (DoD).
We all know that USSF-51 is probably going not a spy satellite tv for pc. ULA has launched each Orion sign intelligence spacecraftand KENNAN high-resolution imaging missions up to now, however these launches are sometimes given Nationwide Reconnaissance Workplace (NRO) designations reasonably than USSF identifiers. Different Area Pressure Atlas V missions have launched World Area Situational Consciousness Program (GSSAP) satellites which examine adversary spacecraft, Area-Base Infrared System (SBIRS) satellites which give early warning of ballistic missile launches, and Superior Extraordinarily Excessive Frequency (AEHF) satellites which facilitate communications between giant networks of ships, plane, and floor forces.
These three lessons of spacecraft are the almost definitely candidates for USSF-51’s payload. In response to Area Operations Command (SpOC), the subsequent GSSAP satellite tv for pc was scheduled to be deployed this yr [3]. This could be probably the most believable identification for the latest member of the Area Pressure’s fleet based mostly on present knowledge. Nevertheless, USSF-51’s true identification will doubtless stay mysterious for a while to come back. “It’s some of the crucial payloads we’ve put updated,” stated ULA Vice President Gary Wentz [4].
Bruno confirmed that Atlas V efficiently reached orbit [5]. This introduced its 58th and ultimate navy mission to a detailed. USSF-51 was additionally ULA’s 100th mission for the DoD, its anchor buyer. The Atlas household of rockets has a protracted and proud historical past of defending america’ nationwide safety. The preliminary Atlas variant, the SM-65, was America’s first intercontinental ballistic missile. It established nuclear deterrence with the Soviet Union on the peak of the Chilly Battle. Subsequent Atlas configurations had been paired with the light-weight, environment friendly Centaur higher stage to allow orbital launches. Quite a few upgrades have allowed the Atlas household to position a gradual string of navy payloads into orbit for over six a long time, starting with the MIDAS missile warning satellites in 1960.
Finally, the Atlas V was priced out of the market by SpaceX’s inexpensive Falcon household. Starting in 2015, ULA started creating the Vulcan rocket, a extra reasonably priced successor to the heritage Atlas and Delta autos which is able to in the end turn out to be partially reusable. Because of Vulcan, ULA received the lion’s share of the NSSL Part 2 contract and is well-positioned to play a keystone position within the upcoming Part 3. The brand new rocket is at the moment scheduled to take over the Atlas V’s navy workload on the finish of this calendar yr. ULA hopes that Vulcan will proceed the corporate’s enviable 100% mission success charge for years to come back.
As for the Atlas V, it nonetheless has 15 launches left on its manifest. These remaining rockets will deploy one satellite tv for pc for ViaSat and the primary eight clutches of satellites in Amazon’s Kuiper megaconstellation. Different Atlas boosters will launch Boeing’s Starliner capsule to the ISS on six crew rotation missions for NASA. Due to this fact, ULA’s workhorse rocket will often grace the Area Coast by means of the tip of the last decade.
