Aviation Electronics Technician 1 - Historic Naval Ships Association

CHAPTER 8COMPUTERSAs late as the middle 1970’s, the phrase “kick thetires and light the fires” was the main theme inlaunching an aircraft sortie. This meant that as longas there was an airframe with nothing falling off, anengine that would start and achieve takeoff speed, andair in the tires, the aircraft would be launched. Thiswas done so the pilots would get their flight timeevery month. Now the mission has become the primeobjective of the aircraft. This is not meant to belittlethe importance of the engine and airframe.Obviously, they are important, but the aircraft andpilots are designated to perform certain missions. Theperformance of these missions is dependent upon thestatus of the various avionics packages. If one ormore of these packages are degraded or not workingat all, the aircraft is considered to be partial missioncapable or not mission capable.This lack of mission capability has thrust many anavionics work center supervisor into the spotlight. Ifyou are one of the supervisors who has been there,then you know how pleasant the maintenance chief isto you. It is then that you realize that aircraftmaintenance is not a game. As we head toward the21st century, newer and more sophisticated aircraftare being designed and built. The avionics systemsare becoming more complex, thus allowing theaircraft to perform more difficult missions. Theincreased complexity forces the solutions to problemsin microseconds. The only system capable ofperforming these solutions is the computer. In turn,each associated avionics system will act as a sensorthat feeds continuously updated information to thecomputer. The computer processes the data and sendsout information to where it is needed.Because computers are used so extensively inNavy aircraft, the avionics supervisor must have abasic understanding and working knowledge ofcomputers.COMPUTER MAKEUPLearning Objective: Identify computerhardware and software.The electronic components of a computer arecommonly called hardware. Examples of computerhardware are cathode-ray tubes, transistors,microchips, printed circuit cards, etc. Software, onthe other hand, is a term that is applied to a set ofcomputer programs, procedures, and possiblyassociated documentation concerned with theoperation of a data processing system. Softwareincludes compilers, assemblers, executional routines,and input/output libraries. The advances in computersoftware provide the industry with the greatest realmof application possibilities. The problem ofattempting to communicate with a computer has led tothe development of symbolic languages that approachhuman language. The fact that a person can tell acomputer what to do, just as one directs the actions ofanother person, has been made possible by theadvances in software.Software is also used to overcome designdeficiencies in computers. Programming arounddesign deficiencies is a common practice in thecomputer industry. Software is, in fact, often used todetermine design feasibility. The practice ofdesigning a computer with a computer is a commonpractice of design engineers.Perhaps the best software application has been inthe area of real-time processing. Real-timeprocessing is a situation where the data is submitted toa computer, and an immediate response is obtained.The capability of a computer to perform real-timeprocessing could determine the success or failure ofan aircraft’s mission.Programming in a universal language has led tothe development and refinement of a number ofcomputer languages. Many of these languages are fora special area or purpose. For example, FORTRAN(FORmula Translator) for business and scientificprograms, COBOL (COmmon Business OrientedLanguage) for business, and Jovial for large scale,computer-based, command and control systems.PL/1 (Programming Language/one) is a language forreal-time systems. Each of the languages fulfills aspecific need for a specific problem, but lacks theuniversal ideal application.8-1