Main Engine Cut Off

Cygnus, Antares, Atlas V, and NGL

With the launch of OA–7, I’ve been thinking about the interplay between Cygnus, Antares, Atlas V, and Orbital ATK’s Next-Generation Launch Vehicle.1

Let’s start with a bit from Jeff Foust’s latest article on Cygnus for SpaceNews:

Orbital ATK is one of three companies that received follow-on CRS-2 cargo contracts from NASA in early 2016 to deliver cargo to the ISS into the 2020s. Orbital’s contract includes options for Cygnus launches on either the Antares or Atlas 5.

Culbertson said that the company expects to hear from NASA in the near future about the mix of launch vehicles it wants for those missions. “On CRS-2, NASA hasn’t actually told us exactly which missions they’ll want on which vehicles,” he said. “We’re waiting to see which way they’d like for us to go, whether it’s a mix or all one or the other. We hope to hear that pretty soon.”

It made a lot of sense for Orbital to take advantage of available Atlas V slots in the wake of the Orb-3 failure. Integrating new engines was going to take a while, and Orbital ATK had a contract to fulfill.

And then after OA-5, Orbital and ULA announced that Cygnus would again fly on an Atlas V—the first use of ULA’s RapidLaunch program. This time it made sense because NASA needed the extra upmass, and Orbital could eliminate the need for one additional Antares flight to finish out their original CRS-1 contract. Orbital sees the math working out in the long-term: one slightly-more expensive flight on Atlas V beats two slightly-less expensive flights on Antares.2

Yet through all these actions and justifications, Orbital ATK may have brought about the end of Antares.

ULA is making huge strides on cost-reduction. A base-level Atlas V 401 now starts at $109 million, and a Cygnus flight probably costs something in the $200-250 million range all said and done.

Antares’ Achilles’ heel is its low flight rate and lack of use, other than for Cygnus. That means Orbital will have a tough time bringing down its cost.

Antares is in that position because frankly, it isn’t that useful. It has a small payload capacity with only a 3.9-meter fairing, and more importantly, it can only launch from Wallops, which means it can’t fly useful missions to polar orbits or GTO. And yet another concern: it uses RD-series engines, which would become a liability if they ever wanted to use Antares for national security flights.

At the same time, Orbital is putting a lot of effort into the development of NGL and is focused on making it cost-competitive with the Atlas V. NGL addresses every drawback of Antares. NGL will fly from Kennedy Space Center (Pad 39B) and Vandenberg (SLC-2), which means it can fly anything from low-inclination LEO and GEO flights, to polar and other high-inclination flights. It also will fly with a 5-meter fairing, all-American propulsion, and a competitive payload capacity (including direct injection to GEO capability). Overall, NGL is a far, far more useful launch vehicle that could compete for contracts with ULA and SpaceX.3

I wouldn’t be surprised if Orbital ATK retired Antares after their initial 20-engine (10-flight) contract is up with Energomash, opting instead to fly on Atlas V and/or Vulcan until their own NGL is ready.

In retrospect, it will be Orb-3 that ended Antares. But it wasn’t because of the failure, it was because of the timing.

  1. I can’t stand writing that all the time. Orbital ATK better name this launch vehicle soon. ↩︎

  2. The unverified (and probably unverifiable, since neither party will talk) cost numbers I’ve heard are around $200 million for an Antares-Cygnus flight, and $200-250 million for an Atlas-Cygnus. ↩︎

  3. I use the phrase “could compete” in the sense that it will be technically able to be entered into a contract competition. Whether or not it will be economically viable is another discussion entirely. ↩︎