Falcon 9 second stage engine test.
“A 60-second long test firing of the Falcon 9 Flight 3 second stage, conducted at the SpaceX Test Facility in McGregor. Texas. The Merlin Vacuum second stage engine generates 92,500 lb of force in vacuum, and operates with a vacuum specific impulse of 342 seconds — the highest efficiency ever for an American hydrocarbon rocket engine. In flight the engine ignites about 3 minutes after launch, delivering the Dragon spacecraft to orbit about 6 minutes later.” -SpaceX