B747 slipper rakett - Curt Lewis

Gammel ide får nytt liv. Ealy nineties: Orbital Sciences began to use a converted L-1011-100 named Stargazer to launch Pegasus rockets into orbit around Earth.
(Red.)

Virgin Orbit 'drop tests' a rocket from a 747 aircraft 35,000 feet in the sky

Virgin wants to launch a rocket off a 747

New York (CNN Business)People near the Mojave Desert may have caught a strange sight Wednesday morning: A 70-foot rocket plummeting from the sky.

It's was part of a pre-planned test carried out by Virgin Orbit, the space startup backed by British entrepreneur Richard Branson. The company wants to fire satellites into orbit using rockets that launch mid-air from under the wing of a plane. Wednesday's spectacle, during which a Virgin Orbit LauncherOne rocket was intentionally left to freefall back to the ground for a "drop test," was the final step toward reaching that goal.

LauncherOne took off from a Mojave runway nestled beneath the wing of a modified Boeing 747 airplane, nicknamed Cosmic Girl. Once the plane reached about 35,000 feet, the typical cruising altitude for commercial aircraft, the rocket was released. It then slammed to the ground at a test range at Edward's Air Force Base.

During operational missions, the LauncherOne rocket would fire up its engine shortly after detaching from Cosmic Girl's wing and continue flying into orbit in order to drop off satellites for Virgin Orbit's customers. But for the drop test, a dummy rocket was used to simulate the entire commercial flight experience - just without the part where the rocket zooms off into orbit.

Virgin Orbit said in a blog post that it would be "monitoring and rehearsing a million things" during the drop test - but it was primarily intended to "ensure the rocket and aircraft separate cleanly" and allow engineers to "observe how the rocket behaves" during freefall. It was the last planned test flight before Virgin Galactic will attempt an orbital mission.

CEO Dan Hart told CNN Business on Wednesday after the flight that initial data reports about the test "were absolutely perfect."
"We are really locked in, starting this afternoon, on focusing on our first orbital rocket and getting the aircraft and the equipment ready," Hart said.

The big business of smallsats

The company says its LauncherOne rocket will be able to thrust 500 kilograms, or 1,100 pounds, into orbit - enough lift capacity for a batch of small satellites, or smallsats.
As satellite technology has grown cheaper, the demand for less expensive and more frequent rocket launches has swelled. Numerous startups are trying to answer that demand by building cheap, lightweight rockets that will be dedicated to launching miniature satellites.

Virgin Orbit is set to start competing with the likes of US-based startup Rocket Lab, which is the only dedicated smallsat launch company that's currently operational.
Virgin Orbit already has customers lined up.

The company stands apart from its rivals by opting for an air-launched rocket. The vast majority of launch vehicles take off vertically from a ground-based pad.

Flying a rocket to a high altitude before firing its engine can improve the vehicle's efficiency. It doesn't have to waste fuel cutting through the thickest parts of the atmosphere.

But there's also drawbacks. Since it lights up mid-air, engineers can't make last-minute adjustments to the rocket if something goes wrong. And there's the added risk of strapping the large rocket, full of combustible propellants, onto an aircraft with a human pilot. (Kelly Latimer, a retired lieutenant colonel in the US Air Force, pilots Cosmic Girl.)
Virgin Orbit was spun off from Branson's other space venture, Virgin Galactic, in 2017. Galactic is focused on human spaceflight and plans to begin flying tourists on short trips to the upper atmosphere in the second half of next year.

Galactic announced a merger agreement on Tuesday that will bring the company to the stock market, becoming the first space tourism venture to do so.

Virgin Orbit was not part of that deal. But Hart, the CEO, told CNN Business that the company is looking for an influx of cash. He said his team has been "involved in some investor discussions that we started earlier this year."