For only the sixth time so far, the newly upgraded Delta 4 Heavy Booster blasted off for space, delivering payload to Earth orbit.  This time was a new NRO top secret satellite. With the end of the STS program, this improved booster is now the most powerful launch vehicle in the American fleet.  This triple engine booster is a liquid fuel system, and has reacently punched up the power by nearly 40,000 lbs. of thrust each!  The engineering challenges of finding more power out of the same design are exciting to ponder.  Team FREDNET salutes the success of the improved Delta 4 launch system.

"Liftoff of the mammoth Delta 4 Heavy rocket – composed of a trio of liquid fueled common core boosters – finally came at 9:15 a.m. EDT about 3 hours late after a variety of technical issues halted the countdown three times at less than 4 minutes from liftoff from Space Launch Complex 37 on Cape Canaveral Air Force Station, Florida."

http://www.universetoday.com/96052/super-secret-spy-satellite-soars-spectacularly-to-space-on-delta-4-heavy-booster/