Orbital Sciences [ORB] successfully test launched its Antares medium-class rocket Sunday evening from NASA’s Wallops Island, Va., facility.

The test launch was originally to take place April 17, but an umbilical cord connected to the rocket’s second stage became disconnected 12 minutes before scheduled launch. Weather ended up pushing a Friday launch to Saturday and once more to Sunday.

Orbital said yesterday in a statement payload separation took place approximately 10 minutes after the 5 p.m. EDT launch. Mission completion took place nearly 18 minutes after launch once the rocket’s upper stage completed planned maneuvers to distance itself from the payload.

The test flight demonstrated all operational aspects of Antares, including the ascent to space and accurate delivery of a simulated payload to a target orbit of approximately 150 miles by 160 miles, with an inclination of 51.6 degrees, the same launch profile it will use for Orbital’s upcoming cargo supply mission to the International Space Station (ISS) for NASA. Orbital plans for a demonstration mission to the ISS sometime this summer. If the test run to the ISS is successful, Orbital will begin regular cargo resupply flights to the orbiting laboratory through NASA’s Commercial Resupply Services (CRS) contract beginning in the fall. CRS is valued at $1.9 billion.

ATK’s [ATK] Castor 30 upper-stage solid rocket motor supported the successful Antares test launch, according to a company statement. Castor 30 is a large-diameter upper stage motor that fired for approximately two minutes, 33 seconds and produced 73,000 pounds of maximum thrust to help launch the Cygnus mass simulator payload into the proper orbit. ATK said East Aurora, N.Y.-based Moog produced the thrust vector control (TVC) system as part of the Castor 30 motor.

NASA Administrator Charles Bolden said Sunday in a statement the successful launch from the new Mid-Atlantic Regional Spaceport (MARS) Pad-0A makes it the latest spaceport capable of launching to the ISS, opening additional opportunities for commercial and government users. Traditionally a small-class rocket manufacturer, Antares represents Orbital’s first venture into medium-class rockets. Antares is designed to launch spacecraft weighing up to 14,000 pounds into low-Earth orbit (LEO) and lighter-weight payloads into higher-energy orbits.