P A P E R - III Category A : AIRFRAME (AIRCRAFT HAVING AUW BELOW 5700 KG.) ___________________________________________________________ 1. Aircraft Materials Knowledge of effect of various alloying elements used in steel, properties and their use. Knowledge of Heat treatment of Steel and Aluminium. Knowledge of surface hardening processes used on aircraft metals. Knowledge of welding techniques such as gas welding, arc welding, electric welding etc. Knowledge of identification and physical characteristics of commonly used composite materials, plastics, sealants and rubbers and their inspection and repair. Detailed knowledge of metal/ fabric materials used in air- craft structure; the types of defects associated with them; inspection for deterioration, and methods of rectification and reprotection; procedures for testing the soundness of these materials. Doping process. Knowledge of the various methods used for removal of corrosion from common aircraft metals and methods employed to prevent corrosion. Knowledge of types of wood and glue and their characteris- tics, general defects, tests, inspection and repair. Knowledge of cables, chains and sprockets. 2. Aerodynamics Knowledge of the characteristics of the subsonic airflow and the various terms used therein. Knowledge of the characteristics of the aerofoils. Knowledge of the forces acting on the Aircraft during all phases of flight. Detailed knowledge of Aircraft Stability and Control. Knowledge of the effect of altitude,weight,changes of engine power on performance of the aircraft. 3. Aircraft Structures General understanding of the various types of structures used in Aircraft construction, Station Nos. Knowledge of such terms as damage tolerance, aging Aircraft, SSID. Knowledge of fail-safe and safe-life concept. Knowledge of various types of methods used on tubular struc- ture, semi-monocoque fuselage, method of attachment of wing to the fuselage; permanent and semi-permanent joints, their inspection and repair. 4. Aircraft Systems General knowledge of the function, maintenance and inspection of the following : (a) Structure and structural components constructed from metal, glass fibre, glass reinforced plastic, vinyl, perspex. (b) Furnishing materials, paints, surface finishes and associated materials. (c) Elementary flying controls; hydraulics; pneumatics; landing gear; brakes; nose wheel steering; ice and rain protection; fire detection and protection, warning and extinguishing; oxygen; airconditioning and pressuriza- tion systems; wheels; tyres; brakes; antiskid. (d) Windows, doors and emergency exits. 5. Aircraft Instruments and Equipments Detailed knowledge of the procedures of replacement and in- situ operational tests of all instruments (except the engine related instruments) and equipment (except where the use of special test instrument/ equipment is required.) Knowledge of construction of various types of Direct Reading Compass, various related terms used in electricity/ magnet- ism, and compass swing precautions and procedures. 6. Inspection Of Aircraft Knowledge of minor defects, their reporting, investigation and methods of rectification and repair of minor defects, rigging of aircraft, periodical inspection necessary to check the serviceability of the Aircraft, preparation of a brief report with the help of sketches if necessary in case of damage to the Aircraft. Symmetry check, Balancing of control surfaces; duplicate inspection. Detailed knowledge of the various inspections such as heavy landing, lightening strike , overweight landing, abnormal flight loads etc.; Familiarity of the structural manuals, various types of repairs given by the manufacturer therein; incorporation of alternate/ equivalent materials; raising up of modifications, repair schemes to the aircraft during overhaul. Knowledge of terms related to aircraft weighing, prepara- tion/ precautions for weighing, preparation of weight sched- ule, calculation of centre of gravity.