49 C.F.R. § 1544.215 – Security coordinators.

(a) Aircraft Operator Security Coordinator. Each aircraft operator must designate and use an Aircraft Operator Security Coordinator (AOSC). The AOSC and any alternates must be appointed at the corporate level and must serve as the aircraft operator's primary contact for security-related activities and communications with TSA, as set forth in the security program. Either the AOSC, or an alternate AOSC, must be available on a 24-hour basis.
(b) Ground Security Coordinator. Each aircraft operator must designate and use a Ground Security Coordinator for each domestic and international flight departure to carry out the Ground Security Coordinator duties specified in the aircraft operator's security program. The Ground Security Coordinator at each airport must conduct the following daily:
1. (1) A review of all security-related functions for which the aircraft operator is responsible, for effectiveness and compliance with this part, the aircraft operator's security program, and applicable Security Directives.
2. (2) Immediate initiation of corrective action for each instance of noncompliance with this part, the aircraft operator's security program, and applicable Security Directives. At foreign airports where such security measures are provided by an agency or contractor of a host government, the aircraft operator must notify TSA for assistance in resolving noncompliance issues.
(c) In-flight Security Coordinator. Each aircraft operator must designate and use the pilot in command as the In-flight Security Coordinator for each domestic and international flight to perform duties specified in the aircraft operator's security program.