Launch of the Antares medium-lift rocket this week will open up a new East Coast spaceport within sight of the Washington Monument.

If all goes well with the inaugural flight of the Orbital Sciences Corp. commercial cargo carrier, the upgraded sounding-rocket facility on Wallops Island, Va., will send spacecraft to the International Space Station (ISS) and the Moon before the year is out.

Down the road, Orbital sees the state-owned facility as the starting point for scientific, military and commercial missions in the Delta II class, including polar-orbiting spacecraft.

Liftoff of the first Antares on its Commercial Orbital Transportation Services (COTS) test flight is set for 5 p.m. April 17, with an instrumented Cygnus cargo carrier on top. Launch attempts on the following two days also are possible in case of weather or other delays at the new oceanside pad.

The first flight has been designed to demonstrate Antares's ability to launch separate stages safely and inject a payload into orbit.

“Our total mission elapsed time will be about 20 minutes for the booster itself,” says Michael Hamel, Orbital's senior vice president for corporate strategy and development. “The payload itself, the simulated mass, will actually get injected into orbit [and] will be in orbit for many months.”

If the mission goes as planned, the company hopes to be able to meet its final COTS milestone by mid-summer with a mission to berth its Cygnus cargo carrier with the ISS and deliver cargo. And if that hurdle is passed, the company could launch its first commercial resupply mission by year-end under its eight-flight, $1.9 billion fixed-price Commercial Resupply Services (CRS) contract with NASA.

The Italian-built pressurized cargo vehicle for the final COTS flight already has been packed and integrated with its Cygnus service module, which Orbital built at its Dulles, Va., satellite facility. Once the mission is completed the company will receive the final payout in its $288 million COTS deal, and begin a CRS sequence that will last through 2016, depending on traffic at the ISS.

By launching from Wallops Island, the company expects to avoid the conflicts that complicate scheduling at Cape Canaveral. And it will open up a second East Coast orbital launch site the company hopes will add to its bottom line well beyond the end of the station-resupply contract.

NASA plans to use a solid-fuel Minotaur V launch vehicle at Wallops late this summer to launch the Lunar Atmosphere and Dust Environment Explorer spacecraft into orbit around the Moon to study its scant atmosphere, near-surface environment and the movement of lunar dust. Orbital already has launched Minotaur 1 missions from Wallops, and has a higher-capacity Minotaur VI vehicle that can fly from one of the two Minotaur pads on the island.

The liquid-fueled Antares marks a step up from the comparatively simple ground systems needed for the Minotaur, and it has delayed Orbital's closeout of the COTS work while the Mid-Atlantic Regional Spaceport, developed by the state of Virginia, worked on the complex plumbing and electronics needed to launch the kerosene-fueled Antares.

“Although we've experienced some delays in the build, test and checkout of the pad, the fact is we've gone through a number of exercises with fueling simulations and the rest of that, and every time you do that you get better at it,” says Hamel.

The new rocket uses surplus Russian engines refurbished by Aerojet, and a first stage built in Ukraine. It will deliver the medium-lift capability of the retiring Delta II; Orbital hopes to use the new rocket to capture some of that market.

“We're going to intensify our efforts in marketing the Antares vehicle beyond the CRS vehicle,” Hamel says, noting that for the past 25 years almost 40% of U.S. expendable launches have fallen in the medium-lift range.

The Wallops position at 37.8 deg. N. Lat. imposes a performance penalty on launches compared with those from Cape Canaveral to the south. But the Antares/Cygnus combo, optimized for cargo delivery to orbit without return to the surface, gives it more capacity than the SpaceX Falcon 9/Dragon stack also developed under the COTS program.

Initially Cygnus will be able to transport 2,000 kg (4,409 lb.) of cargo to the ISS. After the third flight it will be upgraded with a more powerful ATK Castor 30XL upper stage and weight reductions in the Cygnus to enable it to carry 2,700 kg. Given the geography of the Virginia coastline, with open ocean to the south, it should be able to put payloads in Sun-synchronous polar orbits “with a modest dogleg” maneuver after launch, Hamel says.

Ultimately Orbital hopes to use the MARS facility as a mini-Cape Canaveral, launching medium-size spacecraft—including those it builds at Dulles—for government and commercial customers, and maintaining a steady launch “cadence” to hold down cost.