By the time you have reached the E-5 or E-6 level, you have acquired many skills and a large amount of theoretical knowledge. Among other things, you have learned aboutConstruction details, operating principles, and operating characteristics of all types of naval propulsion plants and associated engineroom auxiliary machinery; propulsion plant layout and piping system arrangement; theory of combustion, theory of energy transformations, and factors governing engineroom and fireroom efficiency; nature and theory of engineroom operations; operational troubleshooting; engineering casualty control; engineroom maintenance and repair; characteristics of metals and alloys; tests and inspections of main engines; characteristics and tests of lube oil; and records, reports, and other administrative requirements.

As you well know, this is only a partial list of the skills and knowledge you must have in order to qualify as an expert Engineman. But even a very wide range of abilities and an extensive theoretical knowledge will not, in themselves, guarantee your success as an instructor.