Merlin, SpaceX’s new breed of rocket engines, has finally achieved flight qualification for use on the company’s mission-ready rockets.

The Merlin 1D engine was put through its paces: a total of 28 tests including 1,970 seconds of total testing time. SpaceX says that time is the same amount of time it would take Merlin to complete 10 full missions, making the engine more than capable fo flying on the Falcon 9 rocket.

“The Merlin 1D successfully performed every test throughout this extremely rigorous qualification program,” said SpaceX founder Elon Musk in an emailed statement on the news.

“With flight qualification now complete, we look forward to flying the first Merlin 1D engines on Falcon 9’s Flight 6 this year.”

The first flight of the Falcon 9/Merlin 1D combo will be the low-Earth orbit launch of a weather and communications satellite for the Canadian Space Agency. Later this year, Merlin is set for a geosynchronous transfer orbit (GTO) launch.

The latest iteration of the Merlin engine began development two years ago. A new feature for the Merlin 1D is the ability to throttle from 100 percent to 70 percent. Other improvements center around increasing reliability, optimizing performance, and decreasing cost and time for manufacturing the engines.

Image credit: The Walt Disney Company