As in all other evolutions, the observance of proper safety procedures is also an important consideration when performing PMS. It is extremely important that personnel involved in maintenance are thoroughly trained in safety practices. Nothing can replace good common sense when performing any kind of task, but awareness of the specific hazards of a given job will save lives and prevent damage to equipment. Maintenance Requirement Cards (MRCs) have warnings and cautions inserted immediately before the procedural step they apply to and should be obeyed as closely as possible. Any discrepancies or inadequacies in PMS safety procedures should be reported immediately via an urgent PMS Feedback Report. Navy Safety Precautions for Forces Afloat (OPNAVINST 5100) contains safety instructions and precautions to be used when performing PMS.

SPECIAL SAFETY MARKINGS

Index marks and safety lines are painted on or near ordnance equipment and are used by the GM to indicate a complete mechanical function and to indicate safe areas.

An example of the index mark is the breech-closed index painted on the gun housing (fig. 12-16). The index mark shows at once whether the breechblock rises promptly to full breech-closed position, or is sluggish, or sticks. Some guns also have index marks on the housing and slide to indicate full return to the battery. These index marks tend to wear off and require periodical freshening up. Be careful not to get the paint on any other part of the sliding surfaces.

Safety lines mark off safe working areas. Circular safety lines are painted on the deck around a gun mount to indicate the areas you should stay out of when the gun is being trained. "Blast area" lines are painted on the decks around rocket launchers to show how far away you must get to be safe from the hot-rocket blasts. Similar safety lines are necessary to show safe working areas around overhead conveyors and other machines that may be dangerous to personnel who fail to keep away from working parts.

SUMMARY

Gun maintenance involves a wide variety of skills and knowledge. However, all of the skill and knowledge in the world are useless without a high degree of personal dedication to your job and the people around you. The dangers involved in gunnery are readily apparent. Your vigilance as a maintenance technician may well make the difference between a successful gunshoot or missile launch and a catastrophic

Figure 12-16.-Breech-closed index mark.

accident. Take the time to learn your system and never assume anything.

In this chapter we have discussed the various maintenance requirements involved in keeping a gun and missile system operational. We described the important foundational role preventive maintenance

plays in both system readiness and your personal development as a technician. We described the lubricants and tools used in routine maintenance as well as the reference publications that provide in-depth information about the operation, upkeep, and repair of

your gun or launcher. We described some specific maintenance actions that you will be involved in, such as barrel maintenance, replacement of hydraulic seals, and mechanical adjustments. We also discussed some maintenance-related safety precautions. We concluded with a brief discussion of PMS, quality assurance, and safety.