Northrop Grumman ready for space station resupply mission – Spaceflight Now

Northrop Grumman will launch the penultimate flight of its current Antares rocket configuration — with Russian engines and a Ukrainian first stage structure — to begin a resupply mission on Sunday that will deliver more than four tons of cargo to the International Space Station.

The current Antares rocket configuration, known as the Antares 230+, will be retired next year to allow Northrop Grumman and partner Firefly Aerospace to develop a new US-made booster to replace the Ukrainian/Russian design for future cargo flights in the space station.

Northrop Grumman’s 18th resupply mission to the space station begins Sunday at 5:50:16 a.m. EST (1050:16 GMT) with a launch from Virginia’s Eastern Shore, opening a five-minute launch window. Two Russian-made RD-181 engines will power Path 0A’s 139-foot-tall (42.5 meters) rocket at the Mid-Atlantic Regional Spaceport in Virginia, along with NASA’s Wallops Flight Facility on the Atlantic coast.

The official weather forecast for the launch calls for an 80% chance of favorable conditions for the launch before sunrise Sunday.

The kerosene-powered RD-181 engines will throttle to generate 864,000 pounds of thrust and burn for 3 minutes and 18 seconds, sending the Antares rocket from Virginia to the southeast on a path to align with orbit. from the space station. The Ukrainian-built first stage is jettisoned seconds after engine shutdown, followed by the missile’s nose cone drop at T+plus 3 minutes 54 seconds, and ignition of the US-made solid rocket motor of the top stage on T+plus 4 minutes and 7 seconds for a burn time of almost three minutes.

The rocket will launch Northrop Grumman’s Cygnus freighter into orbit nearly seven minutes after launch. The supply ship will detach from the upper stage of Antares at T+plus for 8 minutes and 52 seconds, allowing the Cygnus spacecraft to open its fan-shaped solar panels and chase the space station.

Assuming a timely launch on Sunday, the freighter Northrop Grumman will arrive at the station early Tuesday. NASA astronaut Nicole Mann will operate the station’s robotic arm to capture the Cygnus spacecraft and place it at a docking station in the Unity module of the Earth-orbiting lab for a nearly three-month stay.

The mission is designated NG-18 and marks the 18th Cygnus spacecraft flying to the space station. Northrop Grumman has a multi-billion dollar cargo supply contract with NASA for Cygnus missions over NG-25.

But two of Northrop Grumman are switching from two of its main suppliers after supply chain tensions caused by Russia’s invasion of Ukraine earlier this year. NPO Energomash, a Russian rocket engine builder, produces the RD-181 engines used in the first stage of the Antares 230+ rocket. And the structure of the first stage itself was designed and built by the Ukrainian companies Yuzhnoye and Yuzhmash.

“We’ve had great support from those three suppliers,” said Kurt Eberly, Northrop Grumman’s director of space launch programs. “Technically things work very well on the vehicle and programmatically we have had great support from them. I wish it could have gone on, but this is also an opportunity for us to move into what we think will be a more competitive vehicle. ”

In August, Northrop Grumman and Firefly Aerospace announced a partnership to develop a new US-built Antares first stage booster powered by seven Miranda engines developed by Firefly. That rocket, called Antares 330, is scheduled to launch in late 2024.

Northrop Grumman had two sets of engines and two Antares boosters in the United States first stage when Russia invaded Ukraine in February, enough to cover the company’s needs for the NG-18 and NG-19 missions. Following the launch of NG-19 on the final Antares 230+ rocket, currently scheduled for March, Northrop Grumman will launch the next three Cygnus cargo missions on SpaceX Falcon 9 rockets from Cape Canaveral in 2023 and 2024.

Falcon 9 rockets are already launching SpaceX’s own resupply missions to the space station with the Dragon spacecraft. Unlike the Dragon, the Cygnus supply ships will launch under the cockpit of the Falcon 9. Eberly said in August that Northrop Grumman had booked the launches of the NG-20, NG-21 and NG-22 at SpaceX using the own internal financing of the company.

Officials hope the Antares 330 rocket will be ready to resume cargo launches from the space station from Virginia in late 2024 for the NG-23, NG-24 and NG-25 missions, the last three cargo flights on Northrop Grumman’s current contract with nasa.

Northrop Grumman and Firefly officials hope to attract more customers for the Antares 330 rocket than cargo launches in the space station. The companies are also planning a new rocket design currently called the Medium Launch Vehicle, or MLV, which will replace the Antares 330. The new MLV will have a liquid fuel upper stage to replace the solid fuel engine used on the Antares 230+ and Antares 330.

Eberly said the Antares 330’s seven main engine configuration is “compatible” with future attempts to perform propulsive landings with the booster.

“We’re building in the ability to reuse later in that development,” Eberly said. “We’re going to start with a replaceable version and we’ll bring it back in later, is the plan.”

In a pre-launch press conference on Saturday, Eberly said the fallout from the Russian military attack on Ukraine did not affect preparations for the NG-18 mission.

“We’re doing all the work on all the hardware … and we had all the hardware here before the launch of NG-17 for the NG-18 and NG-19 missions,” Eberly said. “So it’s really been untouched.”

Ground teams assembled the first and second stages of the Antares rocket and then installed the Cygnus payload and nose cone in a horizontal integration facility in Wallops. Northrop Grumman rolled the rocket to pad 0A on Wednesday at the Mid-Atlantic Regional Spaceport, a facility operated by the Virginia Commercial Space Flight Authority.

After guiding the Antares rocket up the ramp on pad 0A, ground teams engaged a hydraulic lift to raise the launcher vertically later on Wednesday to begin a series of preflight checks. A combined systems test was completed on Thursday to verify the interfaces between the Antares rocket, the Cygnus freighter and the NASA-operated range at Wallops.

Workers then lowered the Antares rocket horizontally again and moved a mobile cleanroom over the top of the launcher’s shell. Technicians opened the top of the fairing to access the forward hatch of the Cygnus spacecraft for loading time-sensitive cargo and experiments early Saturday.

The Antares team closed the Cygnus hatch, installed the top of the Antares payload fairing and raised the rocket vertically again on Saturday to begin the countdown for the five-hour launch at 1:50 a.m. EDT (0550 GMT). ) Sunday, Eberly said. .

The change from daylight saving time to standard time at 2 a.m. will occur during the Antares countdown. The launch team will oversee final activation, readiness checks and filling the first stage of the Antares rocket with kerosene and liquid oxygen propellants before launch.

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