The Army seeks market research information from companies capable of repairing the AN/ASN-157 Doppler Navigation Set (DNS), a critical sensor for AH-64D/E Apache helicopters. This is a Sources Sought Announcement for planning purposes only and is not a request for proposals. The government does not possess the Technical Data Package for these parts. Interested companies must submit capability information, including a completed questionnaire, via email by the specified response date. The performance location is not specified, and no budget information is provided.