ULA Atlas V ready to launch heaviest payload to date with ‘S.S. Rick Husband’
CAPE CANAVERAL, Fla. — Orbital ATK’s S.S. Rick Husband Cygnus cargo vessel is safely cocooned within a four-meter fairing atop a United Launch Alliance (ULA) Atlas V 401 booster at Cape Canaveral’s Space Launch Complex 41 (SLC-41). This mission is being carried out by ULA / Orbital ATK under the $1.9 billion Commercial Resupply Services contract that Orbital ATK has inked with NASA.
Tuesday’s nighttime launch, slated to take place during a 30-minute window that will open at 11:05 p.m. EDT, will be the second of two planned missions that will use an Atlas V 401 prior to the new “Enhanced” Cygnus flies on the 200 version of Orbital ATK’s Antares booster.
An Atlas V rocket, carrying Orbital ATK’s Cygnus™ OA-6 spacecraft, on the launch pad at Space Launch Complex-41 in preparation for launch to the ISS. Photo Credit: ULA
For tomorrow’s planned flight, Cygnus will be hefting an estimated 7,745 lb (3,513 kg) of cargo to the outpost. Cygnus also has an external deployer carrying CubeSats mounted to the outside of the soda can-shaped spacecraft. The OA-6 mission will support or carry out numerous experiments both on and off the space station.
As noted by one representative with the firm based in Dulles, Virginia, there were few changes made between this Cygnus and the one launched on December 6 of last year.
“The differences between the OA-4 and OA-6 vehicles are almost nothing, with the exception of the nanoracks microsat deployer that we have attached to the SM (Service Module). So, besides that, in terms of sensors and structure, it is virtually identical to the OA-4 mission,” Dan Tani, a former NASA astronaut who currently serves as Orbital ATK’s senior director of mission cargo and operations told SpaceFlight Insider in a recent interview. “The intent was to carry the same amount of cargo (as OA-4) – 3,513 kilograms. However, NASA came [to] us with a late request and asked for a few more, so we’re actually four or five kilograms heavier than the last one, so we’re at 3,518 kilograms of cargo.”
Based in Mountain View, California, Made in Space will see their second 3-D printer – the Additive Manufacturing Facility, or “AMF” – launched to the ISS on OA-6. AMF will build upon the lessons learned from the first 3-D printer to be sent to the ISS back in 2014; it will be able to create tools, parts, and experiments on demand from various materials, which include engineered plastics.
Other missions looking to test out concepts in zero-g include “Gecko Gripper” – an experiment which will validate the concept of using artificial setae (the tiny hairs found on the feet of geckos) on robots.
More academic research will also be sent to the ISS in the form of the Meteor Composition Determination (Meteor) experiment which will utilize high-resolution imagery of Earth’s atmosphere to help determine the properties of meteoroid dust.
Also riding the S.S. Rick Husband into the black of space is Strata 1, which is being sent to the space station to study how differing types of regolith behave in low gravity environments. With NASA stating that the space agency is planning to send crews to a boulder plucked from an asteroid via the Asteroid Redirect Mission as well as eventual crewed missions to Mars, Strata 1 could provide critical insights into the nature of loose, rocky material.
When its roughly two-month stint berthed to the orbiting complex comes to a close, the spacecraft’s mission won’t end there. The Saffire-I experiment will initiate the largest purposefully-set fire in space to date. The experiment will use the Cygnus, which will study how a fire of this size behaves in the microgravity environment.
Atlas V 401 launch of Cygnus OA-4. Photo Credit: ULA
Weather conditions are currently predicted to provide an 80 percent chance of favorable conditions for Tuesday’s late-night launch.
The Enhanced Cygnus spacecraft is composed of a common Service Module along with a Pressurized Cargo Module and is constructed at Orbital ATK’s headquarters located in Dulles, Virginia. The cargo vessel can trace its lineage to both the LEOStar™ and the GEOStar™ satellite families.
If the PCM appears familiar, or similar to components already incorporated onto the ISS, it is because it is based on the Multi-Purpose Logistics Module (MPLM). The MPLM was used to ferry cargo to the space station via the space shuttle, which would subsequently be berthed to either the Unity or Harmony modules on the ISS. The MPLMs, built by Thales Alenia Space in Italy, flew to the station some twelve times.
OA-6 will be the last of two planned flights of Cygnus on an Atlas V. The venerable booster will fly in its 401 configuration: a four-meter fairing, no solid rocket motors, and a single Aerojet Rocketdyne RL10C rocket engine in its Centaur upper stage.
Cygnus will ride to orbit safely cocooned in the 4 meter (14-ft) diameter extra extended payload fairing or “XEPF”. The XEPF has an aluminum skin and splits down its center in preparation for spacecraft deployment. With the XEPF, the Atlas V stands an imposing 194 feet (59 meters) in height.
Atlas V is a two-stage rocket with its core booster measuring about 12.5 ft (4 meters) in diameter and 106.5 ft (32 meters) in height. The Atlas V’s first stage gets its power from a single RD-180 rocket engine, the thrust from which is directed via two engine nozzles, which lends the appearance that the rocket has two engines. The RD-180 uses RP-1 (a highly refined version of kerosene) as fuel and liquid oxygen (LOX) as the oxidizer. The RD-180 is capable of delivering an estimated 860,200 lbf (3.83 MN) of thrust at sea level.
The rocket’s second stage is composed of the Centaur, which is about 10 ft (3 meters) in diameter and some 41.5 ft (13 meters) in height. Unlike the RD-180, it is fuelled by a mixture of LOX and liquid hydrogen.
Orbital ATK is currently planning on launching the next Cygnus spacecraft on OA-5 in late May. That mission should see the first flight of the up-rated Antares booster from NASA’s Wallops Flight Facility’s Pad-0A at the Mid-Atlantic Regional Spaceport located in Virginia.
“We like to name our vehicles and spacecraft at Orbital ATK; it’s sort of a tradition that we have. Since we are supporting human space flight, we have chosen to use fallen astronauts as our naming source,” Tani told SpaceFlight Insider. “Rick Husband was a fantastic astronaut and the commander of STS-107 which we lost in 2003 […] we see this as an opportunity to honor Rick and his family.”
SpaceFlight Insider will hold its Live Show from the Kennedy Space Center Press Site, just a few miles from Cape Canaveral’s SLC-41 starting at 10:30 p.m. EDT. Be sure to tune in!
Video courtesy of Orbital ATK
Jason Rhian
Jason Rhian spent several years honing his skills with internships at NASA, the National Space Society and other organizations. He has provided content for outlets such as: Aviation Week & Space Technology, Space.com, The Mars Society and Universe Today.
