NASA announced on Wednesday that the problem would prevent the spacecraft from reaching the ISS as scheduled. Engineers ultimately determined the engine’s early shutdown was caused by onboard software designed to protect the spacecraft from a potential problem.

Data transmitted from the spacecraft back to Northrop Grumman’s mission control center in Northern Virginia confirmed the engine itself operated normally. The premature engine shutdowns were triggered by a conservative software safeguard, according to NASA.

Operating under updated software parameters, the Cygnus spacecraft flew itself to within 30 feet of the space station early Thursday, close enough for Kim to use the robotic arm to reach out and grapple it.

This mission is the first flight of Northrop Grumman’s upgraded Cygnus XL spacecraft, with a cargo module 5.2 feet (1.6 meters) longer than the previous version of Cygnus. This translates to a capacity to carry 33 percent more cargo. The supply load on this mission totals 10,827 pounds (4,911 kilograms), a NASA spokesperson told Ars.

The cargo includes food, oxygen, and nitrogen, and spare parts for the station’s urine processor, which helps convert waste into fresh drinking water. The Cygnus spacecraft also delivered a new navigation aid to be mounted outside the space station to help future crew and cargo ships guide themselves toward the complex.

Among other things, research hardware aboard the Cygnus XL spacecraft will study the production of semiconductor crystals in microgravity and demonstrate a new way to keep cryogenic propellants properly conditioned during long-duration spaceflight.