Virgin Galactic conducts captive carry flight of SpaceShipTwo
WhiteKnightTwo and VSS Unity take off for a captive carry test flight. This was the fourth test flight for VSS Unity. Photo Credit: Virgin Galactic
On Wednesday, Nov. 30, Virgin Galactic conducted the fourth test flight of its SpaceShipTwo rocket plane VSS Unity. The carrier aircraft, WhiteKnightTwo VMS Eve, took off with VSS Unity from the runway of Mojave Air and Spaceport at 2:07 p.m. PST (22:07 GMT).
The two craft remained mated together for the entire flight. At 4:30 p.m. PST (00:30 GMT Dec. 1), the Virgin Galactic Twitter account announced: “VSS Unity and WhiteKnightTwo have just landed. Vehicle and crew are back on the ground after a successful test.”
VSS Unity’s first test flight took place on Sept. 8. The spaceship was piloted by Mark Stucky and Dave Mackay, while VMS Eve was flown by Mike Masucci and Todd Ericson along with flight test engineer Wes Persall.
During the 3-hour, 43-minute test flight, WhiteKnightTwo served as a “flying wind tunnel” allowing the highest fidelity method of testing airflow around SpaceShipTwo while also testing the performance of the spaceship when exposed to the frigid temperatures found at the flight’s maximum altitude of approximately 50,000 feet (15,240 meters).
An infographic of the steps in the SpaceShipTwo testing program. Image Credit: Virgin Galactic
The second test flight occurred on Nov. 1. It was originally intended to include a glide test but high crosswinds resulted in that portion of the flight being canceled.
Weather conditions had improved by the time of the next flight, on Nov. 3, but the glide test was once again postponed.
“As part of our ground and flight testing, we made a few tweaks to the vehicle,” Virgin Galactic tweeted before the Nov. 30 flight. “We’ll test those in a captive carry flight today.”
Virgin Galactic has not announced when the next test flight will take place or if it will include a glide test.
The first glide test, when it takes place, will focus on evaluating the fundamental performance and handling qualities of VSS Unity. The vehicle will be kept at a light weight and a “speed limit” of Mach 0.6 will be placed on the pilots.
Subsequent flights will test the vehicle under a variety of conditions: both heavy (simulating the full weight of a load of fuel, oxidizer, and people) and light (with empty tanks) at a variety of flight paths.
This series of glide tests is designed to demonstrate how VSS Unity will perform as it returns from space after the feathering system is retracted and the spaceship becomes a glider and lands on the runway like an airplane. The phase of flight will also demonstrate and test abort procedures, which will culminate in a safe glide back to the runway.
Rocket powered test flights will begin once the requirements of the glide testing program have been satisfied.
Video courtesy of Virgin Galactic
Jim Sharkey
Jim Sharkey is a lab assistant, writer and general science enthusiast who grew up in Enid, Oklahoma, the hometown of Skylab and Shuttle astronaut Owen K. Garriott. As a young Star Trek fan he participated in the letter-writing campaign which resulted in the space shuttle prototype being named Enterprise. While his academic studies have ranged from psychology and archaeology to biology, he has never lost his passion for space exploration. Jim began blogging about science, science fiction and futurism in 2004. Jim resides in the San Francisco Bay area and has attended NASA Socials for the Mars Science Laboratory Curiosity rover landing and the NASA LADEE lunar orbiter launch.
The takeoff and landing times are off by an hour. They didn’t land in the dark.