Chris Bergin of NASASpaceFlight.com:
During the test, the Starliner was lifted about 40,000 feet in the air, the flying altitude of a typical commercial airline flight, by a Near Space Corp. helium balloon and then released over the White Sands Missile Range, next door to Spaceport America.
Uniquely, this test wasn’t conducted via the use of a helicopter of an aircraft – as seen with other vehicles, such as the Orion spacecraft. Boeing was not able to fit the Starliner test article into the hold of a C-130 or C-17 aircraft, so they instead used a 1.3-million-cubic-foot balloon, which is able to lift the capsule to its intended altitude.
Great rundown of Starliner progress, complete with some talk about RD-180 certification:
“One of the top Boeing risks is the RD-180 engine certification. The engine has a long history, but it has been difficult to get detailed design information for certification,” added the ASAP minutes.
“The Boeing team is developing an approach that takes advantage of the long history of successful use, combined with information that they can obtain.”