Pioneering small satellite air-launch company Virgin Orbit has accomplished its first midair commercial launch mission.

The company founded by Sir Richard Branson launches small satellites.

A small satellite, also called a miniaturized satellite, is a satellite of low mass and small size. It usually weighs fewer than 500 kilograms.

Virgin Orbit's air-launch-to-orbit technique couples a jumbo jet with a rocket designed to take small satellites into orbit. The rocket is slung beneath one of the wings of a modified Boeing 747-400 called Cosmic Girl.

Cosmic Girl drops the 21 meter LauncherOne, which ignites its rockets to enter low earth orbit. Cosmic Girl can launch payloads weighing 400 kilograms.

"A new gateway to space has just sprung open," Virgin Orbit chief executive Dan Hart said in a statement.

"That LauncherOne was able to successfully reach orbit is a testament to this team's talent, precision, drive and ingenuity."

Branson said Virgin Orbit had achieved something many thought impossible.

"It was so inspiring to see our specially adapted Virgin Atlantic 747, Cosmic Girl, send the LauncherOne rocket soaring into orbit," said Branson.

"This magnificent flight is the culmination of many years of hard work and will also unleash a whole new generation of innovators on the path to orbit."