CARTRIDGES AND CARTRIDGE- ACTUATED DEVICES (CAD)

The pilot’s and copilot’s internal initiator handles transfer a detonation wave signal to the connecting SMDC assemblies, which are routed throughout the cockpit area. In turn, the SMDC assemblies initiate four detonating cord assemblies, which are mounted on the periphery of the two canopies and the two hatches. The detonating cord assemblies sever or fracture the stretched acrylic canopies and hatches. FLSC assemblies, which are simultaneously initiated, sever the two wing fillet supports and the two upper wing-to-fuselage fillets, which extend into the TACCO and SENSO hatch area. Actuation of the TACCO or SENSO internal SMDC initiator will sever only the hatch, the upper wing-to-fuselage -fillet, and the wing fillet support at the crew station in which the initiator was activated. Explosive one-way transfers located forward of the TACCO and SENSO crew stations prevent the detonation wave from severing the pilot and copilot canopies. It is virtually impossible to initiate the system at any point other than an initiator handle. As compared to hot-gas systems, this system maybe considered immune to ordinary shop hazards. The system is self-sufficient and independent. It depends upon no other system for aid or assistance, and it does not contribute aid, assistance, or sequence to any other aircraft system. The S-3A system is much less susceptible to inadvertent actuation than hot-gas systems, and hence more convenient and safe for maintenance personnel. CARTRIDGES AND CARTRIDGE- ACTUATED DEVICES (CAD) Learning Objective: Recognize the service life and expiration dates of cartridges and cartridge-activated devices. The types of explosive devices incorporated in egress systems are varied. The AME working with these devices must know how they function, their characteristics, how to identify them, their service-life limitations, and all safety precautions. The AME who understands the importance of all of these factors and who correctly uses the maintenance manuals is better equipped to super- vise and train others. The following manuals are required for the AME to meet the above requirements: 1. 2. 3. 4. 5. Description, Preparation for Use, and Handling Instructions, Aircrew Escape Propulsion System (AEPS) Devices, NAV- AIR 11-85-1 General Use Cartridges and Cartridge Actuated Devices for Aircraft and Associated Equipment (CADS), NAV- AIR 11-100-1.1, NAVAIR 11-100-1.2, and NAVAIR 11-100-1.3 Specific aircraft MIMs OP 4, Ammunition Afloat OP 5, Ammunition and Explosives Ashore SERVICE LIFE The service life of a CAD is the specific period of time that it is allowed to be used. These periods of time are affected by various environmental conditions, which have resulted in the assignment of time limits or overage requirements. These limits are shelf life and installed life. The establishment of service-life limits is based upon design verification tests, qualification tests, and surveillance evaluations. The established limits are approved by the Naval Air Systems Command. Therefore, the establishment of service-life time limits is not arbitrary and must be adhered to as specified. Prior to deployment to areas that do not permit ready supply and servicing of cartridges or cartridge-actuated devices, an inspection must be made of all CAD’s service-life expiration dates. If, during this inspection, it is determined that a CAD will become overage during the period of the deployment, the CAD must be replaced prior to the deployment. Before installation of any CAD, the service-life expiration date of the unit must be checked to ensure that the unit is not overage and will not become overage prior to the next periodic maintenance cycle of the aircraft. During standard depot level maintenance (SDLM), the expiration dates of all installed CADs must be checked. Those CADs assigned to organizational level for maintenance and that have expiration dates prior to the next scheduled inspection after the aircraft is returned to its custodian must be replaced. CADs assigned to depot level for maintenance that have expiration dates falling prior to the next scheduled SDLM should also be replaced. The exception is systems replaced exclusively through the use of a field modification team. Adherence to these procedures 2-23