AP reports that 1 million pounds of solid propellant were ignited "in a split second."
Alliant Techsystems Press Release: ATK and NASA Successfully Test Ares First Stage Development Motor.
PROMONTORY, Utah, Sept. 10 /PRNewswire-FirstCall/ -- NASA and Alliant Techsystems (NYSE: ATK) made history today as they conducted the first test of the Ares I first stage five-segment development solid rocket motor, marking the first steps into a new era of space exploration. It is the most powerful and reliable solid rocket booster in the world, and is planned for NASA's Ares I and Ares V rockets.
The initial data showed the motor performed as designed, producing 3.6 million pounds of thrust and burning for over two minutes. The first stage motor for Ares I measures 12 feet in diameter and 154 feet in length. During the test sensors and gauges collected 650 channels of data to accomplish 46 test objectives. The data from this test will help validate how Ares I will perform in flight.