Cargo, Cargo Everywhere — Cygnus Launch First of Three in Next Two Weeks – UPDATE 2

Orbital ATK will launch its next cargo mission to the International Space Station (ISS) tonight aboard a United Launch Alliance (ULA) Atlas V rocket from Cape Canaveral, FL.  It is just one of three cargo ships heading to ISS in the very near future – a Russian Progress will launch next week and then a SpaceX Dragon the week after that. [UPDATE, MARCH 22, 11:35 pm EDT:  The launch took place at 11:05 pm EDT as planned.  All went well and Cygnus is now in orbit.  Arrival at ISS expected Saturday morning EDT.] [UPDATE MARCH 25, 2:25 pm EDT:  The Atlas V first stage underperformed during the launch.  ULA is investigating.]

The abundance of supplies enroute to the six-member crew reflects both the ongoing needs to supply the outpost – an important consideration when planning for trips further from Earth – and the need to catch up after failures grounded each of the systems in 2014 and 2015.

The Cygnus flight tonight (March 22 Eastern Daylight Time; March 23 GMT) is the second Orbital ATK Commercial Resupply Services (CRS) mission since its Antares rocket exploded 15 seconds after launch in October 2014.    Antares is being “re-engined” with different Russian rocket engines (RD-181s) and is expected to return to flight this summer from its launch site at Wallops Island, VA.  That launch was before Orbital Sciences Corporation merged with ATK and was designated Orb-3 — Orbital’s third operational cargo flight to the ISS. 

In the meantime, Orbital ATK arranged to launch two Cygnus spacecraft on ULA’s Atlas V, which launches to the ISS from Cape Canaveral.  The first was in December 2015 and designated OA-4 (for Orbital ATK-4).  The second is tonight.

Orbital ATK Space Systems Group President Frank Culbertson said yesterday that although the original agreement with ULA was for only these two flights, it may use additional Atlas V rockets in the future depending on NASA’s needs.   NASA recently awarded a second round of CRS contracts and Culbertson said that Orbital ATK offered both Antares- and Atlas V-launched missions.  “It’s really up to NASA in terms of what types of missions they order in the future under the new contract….  We’ve offered both … and it depends on what they need …. We’re prepared to do both.”

The Atlas V capabilities offer more flexibility, for example a 30-minute launch window instead of an instantaneous launch window.  

Tonight’s window to launch OA-6 (Orbital ATK-6, skipping over OA-5, which will be the return-to-flight mission for Antares) opens at 11:05 pm EDT.  Bill Harwood of CBS News tweeted the precise launch time options (all in EDT).

A5/OA6: There are 5 launch opportunities during the 26-min 52-sec launch window:

11:05:52pm
11:13:22pm
11:20:52pm
11:25:14pm
11:32:44pm

— William Harwood (@cbs_spacenews) March 22, 2016 

NASA TV coverage of the launch begins at 10:00 pm EDT.  ULA will also have a live webcast.

Orbital ATK names its Cygnus spacecraft after prominent individuals in the space industry who have passed away.  This one is named the S.S. Rick Husband after the commander of the 2003 space shuttle Columbia mission.  He and six others perished during reentry.   Husband also was the pilot of the first space shuttle to dock with the  ISS in 1999 (STS-96) during its earliest stage of construction.

This is an enhanced version of the Cygnus spacecraft and is carrying
7,900 pounds (3,600 kilograms) of supplies, equipment, and scientific
experiments to the six-person ISS crew.  Three of those six crew members
just arrived four days ago aboard Soyuz TMA-20M.

The pace of operations at the ISS is rather intense right now, starting with the Soyuz TMA-20M launch and arrival on March 18; this OA-6 launch tonight, with arrival at ISS on March 26; launch of Russia’s Progress MS-02 on March 31 with docking on April 2; and launch of SpaceX’s CRS-8 (SpX-8) Dragon mission on April 8 and arrival on April 10.  (All dates are EDT.) 

The SpX-8 launch is the first SpaceX mission to ISS since its SpX-7 mission ended in failure in June 2015 because of a second-stage problem on the Falcon 9 rocket.  SpaceX has successfully launched three Falcon 9’s since then, but this will be the first to ISS.

Russia also suffered a launch failure of one of its Progress resupply missions in April 2015.   Three Progresses have been successfully launched to ISS since then and a new version of the spacecraft, Progress MS, was introduced on the most recent launch in December 2015.  The launch on March 31 is the second (Progress MS-02) of this version of the venerable space station cargo resupply spacecraft that has been in use since 1978 initially for Soviet/Russian space stations and now for ISS. 

Orbital ATK’s OA-6 Cygnus is expected to remain at the ISS for 55 days, meaning that it will still be there when SpX-8 arrives.  This will be the first time both U.S. space station cargo companies will have their vehicles berthed to ISS at the same time.  ISS Operations Integration Manager Kenny Todd noted yesterday that it will be very important that the ISS crew pays attention to what is loaded into which vehicle at the end of their missions:  “We’ll have to get creative in terms of making sure that we don’t put the wrong things in the wrong vehicles when they get ready to leave… because we’re going to be moving a lot of cargo through hatches.”

Dragon is designed to return to Earth and land in the Pacific Ocean, bringing back scientific experiments and other high-value cargo.  By contrast, like all the other cargo ships that supply the ISS, Cygnus burns up on reentry and therefore is filled with trash – a less glamorous, but equally indispensable task.

In this case, not only will Cygnus be burning up on the outside, but on the inside as well.  Scientists will use it to test how fire behaves in microgravity.  The Spacecraft Fire Experiment-1 (SAFFIRE-1) will intentionally start a fire in Cygnus after it leaves the ISS. Instruments inside Cygnus will measure flame growth, oxygen use, and other characteristics.