This is a $6,128,434.00 cost-plus-fixed-fee contract awarded by the Defense Advanced Research Projects Agency (DARPA) to RTX BBN Technologies, Inc. (doing business as BBN Technologies), a subsidiary of Raytheon Technologies Corporation. The contract is for the Helicopter Alert and Threat Termination-Acoustic (HALTT-A) System Program, Phase II. This is a follow-on effort to the initial HALTT-A program. The contract has an ultimate completion date of July 31, 2011. BBN Technologies is a research and engineering services provider that specializes in advanced technology development for the U.S. government, with a focus on areas such as quantum computing, artificial intelligence, and autonomous systems. The contract does not have a set-aside designation.