The second-heaviest haul of cargo ever trucked into orbit by a Cygnus resupply ship is only weeks away from launch, as Northrop Grumman Corp. prepares both the spacecraft and its 133-foot-tall (40.5-meter) Antares 230+ booster on parallel processing tracks at the Mid-Atlantic Regional Spaceport (MARS) on Wallops Island, Va. As outlined earlier this week by AmericaSpace, the NG-14 mission is presently targeted to launch from the pretty seaside environs of Pad 0A no sooner than 29 September, the seventh anniversary of the first-ever arrival of a Cygnus at the International Space Station (ISS). And its three-month mission is expected to deliver a whopping 7,623 pounds (3,458 kg) of equipment, payloads and supplies to the station’s Expedition 63 and 64 crews, a figure only exceeded by the 7,936 pounds (3,600 kg) lifted to orbit by last November’s NG-12.
Northrop Grumman this week revealed that hardware processing for its forthcoming mission to the space station is ramping up for next month’s launch. “Preparations are underway at @NASA_Wallops for the NG-14 #Cygnus spacecraft launch aboard our #Antares rocket,” the firm tweeted on Monday. “Targeted for Sept 29.”
Unlike many other launch providers and payload providers, Northrop Grumman will fulfil both roles on this mission, having built both the Cygnus spacecraft and the two-stage Antares booster which will launch it. “The Antares rocket is currently on the Transporter Erector Launcher (TEL) and final vehicle integration activities are expected to wrap up by the end of the week,” Northrop Grumman’s Vicki Cox told AmericaSpace. “The completed vehicle will then be in a holding pattern for a few weeks awaiting Cygnus’ arrival to the Horizontal Integration Facility (HIF) on 7 September.”
This particular spacecraft, like all Cygnuses flown since December 2015, is of the “enhanced” variety, equipped with a larger Pressurized Cargo Module (PCM) than the now-retired “standard” configuration flown until October 2014. The PCM—whose design is based upon the Multi-Purpose Logistics Module (MPLM), flown aboard the Space Shuttle several times between March 2001 and February 2011—stands 15.9 feet (4.86 meters), about 3.9 feet (1.2 meters) taller than the standard Cygnus.
And although their respective diameters are the same at 10.1 feet (3.1 meters), the enhanced version is about 4,000 pounds (1,800 kg) more massive and can accommodate a bigger payload volume of about 950 cubic feet (27 cubic meters). The enhanced Cygnus also carries low-mass Ultraflex solar arrays, which resemble a fan when fully unfurled in orbit. The NG-14 PCM was mated to its Service Module (SM) on 31 July, ahead of fueling on 1 September and transfer to the HIF on 7 September.
One of NG-14’s most visible payloads, ironically, is one that will not actually begin until after Cygnus departs the ISS in December. The Spacecraft Fire Experiment (SAFFIRE), flying its fifth (and second-to-last) mission, has been provided by NASA’s Glenn Research Center (GRC) in Cleveland, Ohio, and seeks to safely examine the process of combustion, smoke behavior and flame-spreading in the microgravity environment.
Understanding how fire behaves in space and how different materials propagate flames in the near-total absence of terrestrial gravity is acutely needed for the development of future spacecraft. Additionally, it will help to develop operational protocols for dealing with fire emergencies, particularly when crew members do not have the ability to exit their spacecraft or return quickly to Earth.
Each SAFFIRE experiment is conducted inside a self-contained module, measuring 3 feet (0.9 meters) by 5 feet (1.5 meters) and divided into an avionics bay filled with sensors, high-definition video cameras and signal processing hardware and a combustion chamber in which the samples are burned. In July 2016, SAFFIRE-I burned a piece of Solid Inflammatory Boundary at Low Speed (SIBAL) cloth—a cotton blend on a fiberglass substrate—was ignited by a hot wire and secured a record for the largest in-space fire experiment of its type ever conducted.
Its data revealed that flames burn more slowly in larger confined volumes than in smaller spaces, even if environmental conditions like oxygen, pressure and flow-speed are identical. SAFFIRE-II in November 2016 and SAFFIRE-III in June 2017 burned different samples (including specimens of Plexiglas and Nomex) at higher fuel-flow velocities and in May 2020 SAFFIRE-IV—conducted during the departure phase of Northrop Grumman’s most recent Cygnus mission, NG-13—pressed the envelope still further.
In fact, SAFFIRE-IV, the SAFFIRE-V experiment on NG-14 and the final experiment of the series, SAFFIRE-VI, slated to ride the NG-15 Cygnus in March of next year, will run at much lower pressures of around 8.2 psi and a 34-percent oxygen level. These represent significantly higher atmospheric conditions than are found here on Earth and this is expected to increase the energetic vigor of their respective flames.
SAFFIRE-V will actually be the first payload to be loaded aboard Cygnus on 9 September. Initial Cargo Load will begin two days later and it is expected that the cargo ship will be mated to Antares about a week thereafter, with “Late Cargo Load” items set for the 22nd. The bullet-like payload fairing will be installed atop Antares on the 23rd, after which the stack will be rolled horizontally out to Pad 0A and raised to the vertical on the 25th. A final load of critical payloads will be completed in a horizontal configuration on the 28th—with a mobile payload processing facility sealed over Antares’ nose to afford the requisite clean-room conditions—before Antares returns again to the vertical for launch the next day.
Assuming an on-time launch at 10:26 p.m. EDT on 29 September, Cygnus is expected to spend three days in transit to the ISS, before it is grappled and berthed at the Earth-facing (or “nadir”) port of the Unity node at 6:20 a.m. EDT on 3 October. Northrop Grumman noted that these times will be confirmed about a month prior to launch. Current plans are for Cygnus to be detached from the space station on 16 December, after which it will spend about two weeks in autonomous free flight and the SAFFIRE-V runs will be performed.
Another post-departure experiment is Northrop Grumman’s home-grown “SharkSat”, a technology prototype to permit engineers to evaluate emerging technologies in the space environment. “SharkSat is driving rapid innovation in technology development processes,” Ms. Cox told AmericaSpace, “and building Northrop Grumman’s next generation of engineering leaders.” The spacecraft will end its life with a destructive re-entry into Earth’s atmosphere on 30 December, wrapping up a mission of 92 days.
A name for NG-14 is expected to be selected early next month. “Northrop Grumman names each Cygnus spacecraft in honor of individuals who contributed to the United States’ commercial space program or human space exploration in some way,” Ms. Cox told AmericaSpace. “These are often astronauts, but that is not a requirement. The Cygnus program and company leadership choose the name and coordinate with the honoree’s family before an announcement is made.”
Thanks to Ms. Vicki Cox of Northrop Grumman Corp. for her assistance in preparing this article.
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