Northrop Grumman launches the latest Antares on the NG-17

The NG-17 mission to resupply the International Space Station lifted off on Saturday, February 19 at 12:40 p.m. EDT (17:40 UTC). The Northrop Grumman Cygnus spacecraft was launched aboard an Antares 230+ rocket from Pad 0A at NASA’s Wallops Flight Facility in Virginia.

A 75% chance of acceptable weather was projected for Saturday’s launch opportunity. Should weather or any other factor delay the launch, there is a chance of a backup on Sunday at 12:17 PM EDT (17:17 UTC), with a greater than 90% probability of an acceptable weather forecast.

The improved Cygnus spacecraft for this mission was named SS Piers Sellers, in honor of the former NASA astronaut. The vendors were veterans of three Space Shuttle missions – STS-112, STS-121 and STS-132 – which were needed to assemble IS. NG-17 is Northrop GrummanThe seventeenth commercial re-supply mission to the terminal and the company’s sixth under the CRS Phase Two (CRS2) contract.

Chris Gebhardt of NASASpaceflight spoke with Kurt Eberly, Northrop Grumman’s Director of Space Launch Programs, about continuing Scorpion heart program, starting with performance in the company’s previous mission which It was successfully launched in August 2021.

“Performance on both stages was fine,” said Eberle. “Cygnus put the money right where they want to be. Even a little above par. So everything was fine. And every telemetry review went well. And really, it performed really well on the NG-16 in August. Performance Very unremarkable got us to complete that mission and put Cygnus on the right track where they can meet on schedule.”

Building on the history of previous missions flights has also made it possible to improve the performance of cargo deliveries with Antares and swan. This will not only improve Northrop Grumman’s capabilities for upcoming CRS2 missions, but also increase competitiveness with other cargo vehicles such as Dragon And the Dream Supplements At a time when new space stations are being actively developed.

“We’ve really made some targeted investments, both for us and for Cygnus, to increase our competitiveness for CRS2 and drive gains on the amount of goods we can move and services we provide for CRS2. So that started with the NG-12 mission, and the minimum award under CRS2 was six. missions. And this upcoming launch on Saturday is the sixth mission, and we have two more missions that NASA has requested after this one on Saturday.”

“Looking back at that, that performance increase that NASA promised we’d give for the CRS2 decade, I think we’ve done very well in being able to say we’re going to upgrade the car, both the Scorpio side and the Cygnus side and say in our predictability, that’s It’s the mass that we’ll have in orbit, and that’s going to be our ability to provide cargo flexibility in terms of allowing NASA to change the amount of cargo in the final load and then implement a 24 hour delayed load where they can load large amounts of cargo 24 hours before takeoff.”

“All of these key features are outlined in CRS2, and in fact, I will say the benefit of the five CRS2 missions we’ve done so far is that we have a huge amount of flight data to review.”

“We offered NASA a little more cargo for NG-18 and 19. This was enabled by increasing Antares capacity by 70 kilograms. So with NG-17, 8,050 kilograms is our commitment to Cygnus, and then for NG- 18 and 19 we will be increasing that by 70 to 8120 kilograms to the CRS injection orbit, and this is just a reflection of our ability to take and reduce flight data and modernize our models in several key areas.”

Eberle went on to describe a modeling and testing process that allows teams to continually improve their understanding of the Antares launcher’s performance, using flight data from previous missions.

“One of those is the second stage performance model – the solid rocket engine performance model. We were able to do an update and get rid of some reservation now that we have that number of flights under our belt, and that was basically a change to the nominal specific thrust model, an increase slight.”

“Also, our aerodynamic drag model…so it’s hard to tell right away. You know, you can do a wind tunnel test — we’re doing CFDs. [Computational Fluid Dynamics] To predict what the aerodynamic drag will be – but then we work hard, through these tasks we go back to calculate the drag using GNC [Guidance, Navigation & Control] Tools, take flight data and then go through a bunch of simulations to see what we think is the best estimate of aerodynamic drag. “

“By following that up on those five missions, we think we over-predicted a little bit in our models, and so we were able to improve that, and that resulted in a little bit more performance. So these are the updates that we do as we fly more and more missions, and that way we were able to from getting more performance to increasing our competitiveness and increasing the service we provide to NASA.”

As Northrop Grumman continues to improve the capabilities of the Antares and Cygnus system, it continues to deliver operational cargo to the International Space Station. The NG-17 mission will deliver scientific payloads to study cancer, the acceleration of aging in microgravity, and plant growth at the station.

Are you ready for #rocket all? Next launch of Tweet embed #CRS17 He will deliver a groundbreaking achievement #to know to me @space station Help us get back here on Earth! #spacebasedresearch pic.twitter.com/99M2Yk0cKy

– ISS National Lab (ISS_CASIS) February 17 2022

Also on the payload manifest is a new lithium-ion battery system and new hydrogen sensors for the station’s oxygen generation system. A large number of CubeSats that will be deployed from the International Space Station will also be delivered by Cygnus.

Instrumentation preparations for the launch of the NG-17 mission began last summer, Eberly described.

“We started working on the car probably in the timeframe last May/June. We start by installing the motors on the thrust frame, all the way to the back of the core, then we install the feed lines. Then we go through a number of pressure checks where we depress the tanks and look for — our Tight leakage circuits for the motors – and then all the fill and drain lines that get to the ground. It was in the early fall timeframe that we got to this kind of testing.”

The second stage arrived in May [2021]. We installed an avionics section on it. Our Avionics division comes from Chandler, Arizona, where we make and harness all of our avionics. All avionics and harness are pre-installed on the avionics chassis which is a long-sided composite chassis. We ship it here and then it installs on the front of the second stage motor. And then we connect everything and start testing the system, which began in October. ”

“We run a number of system tests to make sure everything is working properly. We also do some interface tests with the band, make sure we can read the remote trace for them. And then we take it out for the C band and UHF FTS tracking [Flight Termination System] Test using their mobile assets to make sure everything is working. It was in the November/December time frame.”

“We mated the stages just before the holiday break, so around Dec. 19. We assembled the aerodynamic in January and then lifted and moved the assembled rocket onto the carrier/erector/operator, which we brought to HIF, the horizontal integration facility. And that’s really when we’re ready for the Cygnus to arrive.” .

The Antares and SS Piers Sellers Cygnus spacecraft are launched to Cushion 0A at NASA’s Wallops Flight Facility. (credit: NASA)

“He went into the hen vertically after being fed with fuel. It happened at the end of January. We lifted them and rotated them to the horizontal position, put them on a rolling pallet, and it was early February. It enabled them to rotate things and they could load the goods to all different azimuths. Inside the charging unit. So they can always load because of gravity here on Earth.”

“After we did the initial loading, we didn’t need to spin it around anymore, so we mated the Cygnus to the front of the Antares, ran a final flight simulation – we call it Flight Simulator 2 – and after we fooled around the rocket flew into a full bird climb with Cygnus powered and engaged .since we have a communication link between the Cygnus, we also route the telemetry for them all the way to the ground. And that’s how that was practiced in that flight simulator. We hand them the navigation data as we go up so that the Cygnus has the current state vector. [its] Memory banks at the time of separation. This just helps them take control of the task and do their appointment planning right away.”

After separating from Antares and taking control of the NG-17 mission, Cygnus is scheduled to rendezvous with the International Space Station on Monday, February 21. Canadarm2 will be used to chase the spacecraft and dock it at the station, where it will be used. Provide supplies, science and storage capacity.

During this residency, Cygnus will also be given a new responsibility for the first time. SS berth sellers will perform a single “re-reinforcement” maneuver to help maintain station height, an ability that was Tested on the OA-9E mission. This capability is being developed to help reduce demand for Russia progress Vehicles to re-enhance the station.

According to Cygnus mission standards, the spacecraft will be loaded with waste and safely ejected at the end of its mission, which is scheduled to last about a month.

(Main image: Antares, taking off. Credit: Brady Kenniston for NSF)