Engineering:Cygnus CRS OA-4

Cygnus CRS OA-4

The CRS OA-4 Cygnus spacecraft approaches the ISS
Mission type	ISS resupply
Operator	Orbital ATK
COSPAR ID	2015-072A
SATCAT no.	41101
Mission duration	Final: 75 days, 18 hours, 15 minutes
Spacecraft properties
Spacecraft	S.S. Deke Slayton II
Spacecraft type	Enhanced Cygnus
Manufacturer	Orbital ATK Thales Alenia Space
Launch mass	7,492 kg (16,517 lb)
Payload mass	3,513 kg (7,745 lb)
Start of mission
Launch date	6 December 2015, 21:44:57 (2015-12-06UTC21:44:57) UTC
Rocket	Atlas V 401 (AV-061)
Launch site	Cape Canaveral Air Force Station SLC-41
Contractor	United Launch Alliance
End of mission
Disposal	Deorbited
Decay date	20 February 2016, 16:00 (2016-02-20UTC17) UTC
Orbital parameters
Reference system	Geocentric
Regime	Low Earth
Semi-major axis	6,781.5 km (4,213.8 mi)
Eccentricity	0.0008
Perigee altitude	397.9 km (247.2 mi)
Apogee altitude	408.8 km (254.0 mi)
Inclination	51.64°
Epoch	9 December 2015, 05:44:31 UTC
Berthing at International Space Station
Berthing port	Unity nadir
RMS capture	9 December 2015, 11:19 UTC
Berthing date	9 December 2015, 14:26 UTC
Unberthing date	19 February 2016, 10:38 UTC
RMS release	19 February 2016, 12:26 UTC
Time berthed	71 days, 20 hours, 12 minutes
NASA OA-4 mission patch Commercial Resupply Services   Cygnus flights

Cygnus CRS OA-4, also known as Orbital ATK CRS-4 and CRS Orb-4, was the fourth successful flight of the Orbital ATK uncrewed resupply spacecraft Cygnus and its third flight to the International Space Station under the Commercial Resupply Services contract with NASA. With the Antares rocket undergoing a redesign following its failure during the Orb-3 launch, OA-4 was launched by an Atlas V rocket. Following three launch delays due to inclement weather beginning on 3 December 2015, OA-4 was launched at 21:44 UTC on 6 December 2015. With a liftoff weight of 7,492 kilograms (16,517 lb), OA-4 became the heaviest payload ever launched on an Atlas V. The spacecraft rendezvoused with and was berthed to the ISS on 9 December 2015. It was released on 19 February 2016 after 72 days at the International Space Station. Deorbit occurred on 20 February at approximately 16:00 UTC.

Spacecraft

Atlas V rocket with Cygnus on Pad 41

OA-4 was the fourth of eight flights by Orbital ATK under the Commercial Resupply Services contract with NASA and the inaugural flight of the larger Enhanced Cygnus PCM. The mission was originally scheduled for 1 April 2015. The Atlas 5 rocket launched in the 401 vehicle configuration with a four-meter fairing, no solid rocket boosters and a single-engine Centaur upper stage.

In an Orbital ATK tradition, this Cygnus spacecraft was named Deke Slayton II after one of NASA's original Mercury Seven astronauts and Director of Flight Operations, who died in 1993. This spacecraft reuses the name Deke Slayton, originally applied to the Orb-3 spacecraft which was lost in an Antares rocket explosion in October 2014.

Manifest

An astronaut captured this image of the spacecraft during launch with the Atlas engines still firing.

The mission was the first flight of the enhanced variant of Orbital ATK's Cygnus spacecraft, capable of delivering more than 7,700 pounds of essential crew supplies, equipment and scientific experiments to the station.

Total cargo: 3,349 kg (7,383 lb)

• Crew supplies: 1,181 kg (2,604 lb)
  • Crew care packages
  • Crew provisions
  • Food
• Vehicle Hardware: 1,007 kg (2,220 lb)
  • Crew health care system hardware
  • Environment control and life-support equipment
  • Electrical power system hardware
  • Extravehicular robotics equipment
  • Flight crew equipment
  • PL facility
  • Structural & mechanical equipment
  • Internal thermal control system hardware
• Science Investigations: 847 kg (1,867 lb)
  • A new life science facility called the Space Automated Bio Lab (SABL) that will support studies on cell cultures, bacteria, and other micro-organisms;
  • A microsatellite deployer and the second microsatellite to be deployed from the space station;
  • The NASA LONESTAR experimental payload consisting of the AggieSat4 and Bevo-2 satellites
    • The AggieSat4 satellite, built by engineering students at Texas A&M University, deploys the smaller Bevo-2 CubeSat stored inside of it;
    • The Bevo-2 CubeSat, designed and built by engineering and computer science students at the University of Texas at Austin;
  • Experiments that will study the behavior of gases and liquids and clarify the thermo-physical properties of molten steel; and
  • Evaluations of flame-resistant textiles.
• Computer Resources: 87 kg (192 lb)
  • Command and data handling
  • Photo and TV equipment
• Spacewalk Equipment: 227 kg (500 lb)
  • A new SAFER jetpack
  • Extravehicular Mobility Unit parts, including legs, gloves, tethers, and batteries
  • Airlock cooling loop parts

Total cargo with packing material: 3,513 kg (7,745 lb)