Atlas V 551 Heavylifter Back in Business for Long-Delayed AEHF-4 Launch for Air Force

United Launch Alliance (ULA) launches its 50th mission for the U.S. Air Force and the 250th flight of a Centaur booster in the opening minutes of Wednesday, 17 October. Photo Credit: Alan Walters/AmericaSpace

The most powerful member of United Launch Alliance’s (ULA) Atlas V fleet—the mighty “551” variant, previously used on eight occasions, from […]