TASK SPECIFIC MAINTENANCE FOR A/C OPERATING IN CORROSIVE AMBIENT CONDITIONS 1. 2. OVERVIEW OF THE JOB Operation codes: -01 Inspections and anti-corrosion treatments at short time intervals -02 Inspections and anti-corrosion treatments at medium time intervals This procedure describes the precautionary measures to be applied to the aircraft airframe to prevent corrosion on aircraft operating in conditions that can contribute to the development of corrosion (Refer to SDS 20-60-00, paragraph "corrosion preventive maintenance"). This procedure gives a list of inspection and protection tasks that may reduce the development of corrosion. It contains two types of tasks: inspections and anti-corrosion treatments at short time intervals, inspections and anti-corrosion treatments at medium time intervals. Depending on the aircraft environment and operation and on the affected areas you can: do the tasks of this procedure only partially, adapt the periodicity of the inspections and of the protection renewal. Each operator should evaluate the environment of the aircraft and determine accordingly the appropriate task(s) and application intervals to ensure an adequate corrosion protection. Paragraph 4. gives examples of maintenance plans which may help operators to limit the risk of corrosion development when aircraft is operated in corrosive ambient conditions. NOTE: Some of these tasks must be performed within the scope of MPD Chapter 5-10. So the application intervals determined by the operator should be equal to or shorter than those specified in MPD Chapter 5-10. LOGISTICS A. References Reference Designation 20-60-00 (SDS) PROTECTION SCHEME 10-10-00-910-801 PARKING THE AIRCRAFT 20-31-00-100-801 CLEANING OF THE AIRCRAFT EXTERIOR 20-31-00-140-801 RINSING THE AIRCRAFT EXTERIOR 20-31-00-350-801 BRIGHTENING/POLISHING OF THE WING AND AIR INTAKE LEADING EDGES 20-60-00-370-814 APPLICATION OF RENEWABLE ANTI-CORROSION PROTECTION PRODUCTS 24-00-00-860-801 ENERGIZATION / DE-ENERGIZATION OF THE AIRCRAFT SYSTEMS 27-00-00-910-801 FLIGHT CONTROL SYSTEM MAINTENANCE AND SAFETY PRECAUTIONS 27-50-00-640-801 GREASING / LUBRICATION OF FLAP MECHANISMS (A/C with engines TFE 731-40) 27-50-00-860-802 EXTENSION / RETRACTION OF THE SLATS / FLAPS FOR MAINTENANCE 27-53-01-220-801 CLEANING / CHECK OF THE FLAP SCREW JACK ACTUATING SCREW (A/C with engines TFE 731-40) 27-53-01-640-802 GREASING OF FLAP SCREW JACKS (A/C with engines TFE 731-40) 27-60-00-860-801 EXTENSION / RETRACTION OF THE AIRBRAKES FOR MAINTENANCE 29-00-00-860-801 PRESSURIZATION / DE-PRESSURIZATION OF THE HYDRAULIC SYSTEMS 32-10-00-640-801 LUBRICATION OF THE MAIN LANDING GEARS (MLG) AND MLG DOORS Page: 1 / 8
B. C. D. 32-10-00-860-801 32-20-00-640-801 53-41-00-220-801 53-60-01-900-801 53-80-09-710-801 57-00-00-210-801 57-41-13-640-801 57-55-13-640-801 57-70-03-640-801 Ingredients and Consumable Products MANUAL OPENING / CLOSING OF THE MLG DOORS LUBRICATION OF THE NOSE LANDING GEAR (NLG) AND NLG DOORS DETAILED INSPECTION OF THE UPPER WING ROOT BOLT RECESSES REMOVAL / INSTALLATION OF THE FUSELAGE FAIRINGS OPERATIONAL TEST OF THE "CIRCLE SEAL" AUTOMATIC DRAINS GENERAL VISUAL INSPECTION OF THE WINGS LUBRICATION OF THE SLAT ROLLERS GREASING / LUBRICATION OF FLAP ROLLERS AND TRACKS (A/C with engines TFE 731-40) LUBRICATION OF THE AIRBRAKE HINGES Designation Additional designation TEMPORARY PROTECTION TYPE I TEMPORARY PROTECTION TYPE II SYNTHETIC GREASE MIL-PRF-81322 P-D-680B WHITE SPIRIT LUBRICANT SPRAY Energy ELECTRICAL HYDRAULIC Miscellaneous DANGER, DO NOT PRESSURIZE HYDRAULIC SYSTEMS PLACARD (LOCAL PROCUREMENT) LINT-FREE CLOTHS (LOCAL PROCUREMENT) BRUSH (LOCAL PROCUREMENT) 3. GENERAL RECOMMENDATIONS FOR PARKING THE AIRCRAFT A. Install the covers on the aircraft (Refer to TASK 10-10-00-910-801). NOTE: The bearing surfaces of the covers on the aircraft must be clean and dry. B. Park the aircraft in a hangar, as far as possible. NOTE: Parking the aircraft in a hangar will prevent the deterioration of the paint. 4. EXAMPLE OF ANTI-CORROSION PREVENTIVE MAINTENANCE PLANS A. The following table gives examples of anti-corrosion preventive maintenance plans which can be applied by operators operating in corrosive ambient conditions: Operation area A/C parking Other factors Examples of maintenance plans A or B In hangar Aircraft operated in saline atmosphere Program 1 Page: 2 / 8
Operation area A/C parking Other factors Examples of maintenance plans Not in hangar In bandwith of 20km from the sea or Frequently operated in saline atmosphere Not in bandwith of 20km from the sea and Not frequently operated in saline atmosphere Program 2 Program 3 Any other No impact Frequently operated in saline atmosphere or In bandwith of 20km from the sea or Use of potential corrosive anti-icing products or More corrosion than the average fleet Program 4 NOTE: Area A: geographical areas with tropical climate (e.g.: Brazil, Dominican Republic, Malaysia, Nigeria, Singapore). Area B: geographical areas with dry climate (e.g.: Iran, Libya, Morocco, Qatar, Saudi Arabia, South Africa, Turkey, United Arab Emirates). Both climates can be present in different areas of a same country (e.g.: Australia, India, Mexico, Venezuela). B. Programs (1) Program 1 (a) Perform an aircraft rinsing once a week (Refer to TASK 20-31-00-140-801). (b) Perform an aircraft exterior cleaning once a month (Refer to TASK 20-31-00-100-801). (c) After each cleaning, brighten the wing leading edges (Refer to TASK 20-31-00-350-801). (d) At "A" check time, perform the tasks of the paragraph 6.. (e) At "4A" check time, perform the tasks of the paragraph 7.. (2) Program 2 (a) For aircraft doing maritime surveillance or flown over salt water at a low altitude, after each day of operation perform an aircraft rinsing (Refer to TASK 20-31-00-140-801) and an engine rinsing (refer to the engine manufacturers' maintenance manual). (b) If not, perform an aircraft rinsing once a week (Refer to TASK 20-31-00-140-801). (c) Perform an aircraft exterior cleaning once a month (Refer to TASK 20-31-00-100-801). (d) After each cleaning, brighten the wing leading edges (Refer to TASK 20-31-00-350-801). (e) Every four months, perform the tasks of the paragraph 6.. (f) At "4A" check time, perform the tasks of the paragraph 7.. Page: 3 / 8
5. (3) Program 3 (a) Perform an aircraft exterior cleaning once a month (Refer to TASK 20-31-00-100-801). (b) After each cleaning, brighten the wing leading edges (Refer to TASK 20-31-00-350-801). (c) Every four months, perform the tasks of the paragraph 6.. (d) At "4A" check time, perform the tasks of the paragraph 7.. (4) Program 4 (a) During winter season: 1 For aircraft doing maritime surveillance or flown over salt water at a low altitude, after each day of operation perform an aircraft rinsing (Refer to TASK 20-31-00-140-801) and an engine rinsing (refer to the engine manufacturers' maintenance manual). 2 If not, perform an aircraft rinsing once a week (Refer to TASK 20-31-00-140-801). 3 Perform an aircraft exterior cleaning once a month (Refer to TASK 20-31-00-100-801). 4 After each cleaning, brighten the wing leading edges (Refer to TASK 20-31-00-350-801). 5 Every four months, perform the tasks of the paragraph 6.. (b) During spring, autumn and summer: 1 For aircraft doing maritime surveillance or flown over salt water at a low altitude, perform an aircraft rinsing (Refer to TASK 20-31-00-140-801) after each day of operation and an engine rinsing (refer to the engine manufacturers' maintenance manual). 2 Perform an aircraft exterior cleaning once a month (Refer to TASK 20-31-00-100-801). 3 After each cleaning, brighten the wing leading edges (Refer to TASK 20-31-00-350-801). 4 Every four months, perform the tasks of the paragraph 6.. JOB SET UP A. Obey the flight control system maintenance and safety precautions (Refer to TASK 27-00-00-910-801). B. Connect the electrical Ground Power Unit (GPU) (Refer to TASK 24-00-00-860-801). C. Connect the hydraulic Ground power Unit (GPU) to the external receptacles for both hydraulic systems (Refer to TASK 29-00-00-860-801). D. Energize the aircraft systems (Refer to TASK 24-00-00-860-801). E. Pressurize both hydraulic systems (Refer to TASK 29-00-00-860-801). F. Fully extend the flaps and slats (Refer to TASK 27-50-00-860-802). G. Fully extend the airbrakes (Refer to TASK 27-60-00-860-801). H. Cut off and drop the pressure in both hydraulic systems (Refer to TASK 29-00-00-860-801). I. De-energize the aircraft systems (Refer to TASK 24-00-00-860-801). J. Install the slat and flap safeties (Refer to TASK 27-50-00-860-802, paragraph "Operation on slats and/or flaps extended"). K. Install the airbrake safeties (Refer to TASK 27-60-00-860-801, paragraph "Operation with airbrakes extended"). L. Place a DANGER, DO NOT PRESSURIZE HYDRAULIC SYSTEMS placard in plain sight in the cockpit. WARNING: DO NOT PRESSURIZE HYDRAULIC SYSTEM 1 WITH MAIN LANDING GEAR DOOR(S) OPEN. IF YOU PRESSURIZE SYSTEM 1, THE DOOR(S) WILL CLOSE. THIS CAN CAUSE INJURY TO PERSONNEL AND/OR DAMAGE TO EQUIPMENT. 6. M. Manually open and safety the main landing gear doors (Refer to TASK 32-10-00-860-801). INSPECTIONS AND ANTI-CORROSION TREATMENTS AT SHORT TIME INTERVALS CAUTION: MAKE SURE THAT THE AIRCRAFT SYSTEMS ARE NOT ENERGIZED. Page: 4 / 8
CAUTION: THE ELECTRICAL CONNECTORS SHOULD BE CONNECTED BEFORE APPLYING TEMPORARY PROTECTION TYPE II. A. If necessary, apply or renew TEMPORARY PROTECTION TYPE II on all the electrical connectors, using a brush. B. General inspection and anti-corrosion treatment CAUTION: DO NOT USE DESALINATED SEA WATER FOR RINSING THE AIRCRAFT. (1) Clean the aircraft (Refer to TASK 20-31-00-100-801). NOTE 1: NOTE 2: If only desalinated water is available, or under cold weather conditions, or in airports not authorizing aircraft rinsing, clean the aircraft with lint-free cloths moistened with P-D-680B. The temporary protection is to be applied on cleaned and dry surfaces only. TEMPORARY PROTECTION TYPE I provides a short time anti-corrosion protection. It should be renewed more often than TEMPORARY PROTECTION TYPE II (Refer to TASK 20-60-00-370-814). (2) Check the aircraft airframe for overall condition. (3) Apply TEMPORARY PROTECTION TYPE I to all the drain holes under the fuselage. (4) Inspect the paint for cracks. NOTE 1: A new coat of paint should be applied as soon as possible to all the areas where the paint is damaged. NOTE 2: TEMPORARY PROTECTION TYPE I can be temporarily used if the paint cannot be renewed. (5) Refer to the LMM for specific precautions to be applied to the engines. C. Inspection of the nose cone CAUTION: DO NOT SPRAY TEMPORARY PROTECTION ON THE PNEUMATIC ACTUATOR BODY AND ROD. DO NOT APPLY TEMPORARY PROTECTION TO THE BONDING PLATE. (1) Open the nose cone. (2) On the nose cone, inspect the seal holder. (3) Apply LUBRICANT SPRAY on the locks and on the lock fastener receptacles. (4) Apply SYNTHETIC GREASE on the locator receptacles. D. Inspection of the lower part of the fuselage (1) Apply TEMPORARY PROTECTION TYPE I on the fairing fasteners, on the APU grid and on the air intakes/exhausts. E. Inspection of the baggage compartment (1) Open the baggage compartment door. (2) Inspect the door frame and the door. (3) Apply TEMPORARY PROTECTION TYPE I on the door frame and to the bare metal parts of the door. (4) Close the baggage compartment door. F. Inspection of the servicing compartment (1) Open the servicing compartment door. (2) Visually inspect the structure inside the servicing compartment. (3) Inspect the door frame. (4) Inspect the door. (5) Apply TEMPORARY PROTECTION TYPE II on the door frame and to the bare metal parts of the door. Page: 5 / 8
7. (6) Close the servicing compartment door. G. Inspection of the main and nose landing gears (wells, landing gears, doors) (1) Inspect the main and nose: landing gears, wells, doors. (2) If necessary, apply a local touch-up of TEMPORARY PROTECTION TYPE II on all the structure sections, equipment supports and equipment. (3) Grease and lubricate the main and nose landing gears : MLG (Refer to TASK 32-10-00-640-801), NLG (Refer to TASK 32-20-00-640-801). H. Inspection of the wings (1) Check the lower and upper skin panels of the wings for corrosion. (2) Inspect the lower and upper skin panels of the flaps, slats and airbrakes for corrosion. (3) Grease/lubricate the flap mechanisms: (A/C with engines TFE 731-40) (Refer to TASK 27-50-00-640-801), (Refer to TASK 27-53-01-220-801), (Refer to TASK 27-53-01-640-802) and (Refer to TASK 57-55-13-640-801). Flap mechanism hinges (Refer to TASK 27-50-00-640-801), (4) Grease/lubricate the slat mechanisms (Refer to TASK 57-41-13-640-801). (5) Grease/lubricate the airbrake hinges (Refer to TASK 57-70-03-640-801). (6) Apply or renew TEMPORARY PROTECTION TYPE I on the lower access door fasteners. INSPECTIONS AND ANTI-CORROSION TREATMENTS AT MEDIUM TIME INTERVALS CAUTION: THE ELECTRICAL CONNECTORS SHOULD BE CONNECTED BEFORE APPLYING TEMPORARY PROTECTION TYPE II. A. If necessary, apply or renew TEMPORARY PROTECTION TYPE II on the electrical connectors, using a brush. B. Inspection of the lower part of the fuselage (1) Remove all the fairings (Refer to TASK 53-60-01-900-801). NOTE: Most of the accesses are already removed through the "Z" check. (2) Inspect the skin of the underlying structure. (3) Inspect the metal fairings. (4) Inspect the fasteners of the fairings. (5) Inspect the fuel compartment. (6) Do the operational test of the "circle seal" automatic drains (Refer to TASK 53-80-09-710-801). (7) Install all the fairings (Refer to TASK 53-60-01-900-801). C. Inspection of the stabilizers (1) Inspect the lower and upper skin panels of the horizontal stabilizer and elevators. (2) Inspect the vertical stabilizer skin panels. (3) Thoroughly inspect the fastener lines. (4) Apply or renew TEMPORARY PROTECTION TYPE I on the access door fasteners. D. Inspection of the wings (1) Remove the lower access doors (Refer to TASK 57-00-00-210-801). NOTE: Most of the accesses are already removed through the "Z" check. (2) Remove the wing tip fairings. Page: 6 / 8
(3) Check the entire skin of the wings for corrosion. (4) Inspect the inner parts of the following box structures for corrosion: leading edge box structures, airbrake lower surfaces, box structures aft of the rear spars, flap shrouds, flap track fairings, servo-actuator box structures, wing tip fairings. (5) Inspect: the aileron hinge fittings, the slat and flap tracks, and the areas in which they are installed, the areas in which the flap controls are attached to the structure, the airbrake hinges, the slat anti-icing piping and the telescopic tubes, the flight control rods and bellcranks, and the structure fittings. (6) For F50 with SB F50-331 (Refer to SB 331), inspect the wing-to-fuselage junction: (a) Inspect the upper surface bolt recesses (Refer to TASK 53-41-00-220-801). (b) Inspect the lower surface bolt recesses and the vertical beams. 1 Check for corrosion. 2 Apply or renew TEMPORARY PROTECTION TYPE II on the lower surface bolt recesses. (7) Inspect the lower and upper skin panels of the wings, flaps, slats and airbrakes. (8) Apply or renew TEMPORARY PROTECTION TYPE II on the trailing edge box structures (rear spars, lower and upper panels). (9) Install the access doors (Refer to TASK 57-00-00-210-801). (10) Apply TEMPORARY PROTECTION TYPE I to the lower access door fasteners. E. Inspection of the main and nose landing gears (wells, landing gears, doors) (1) If presence of anti-corrosion protection, clean the main and nose landing gear wells (Refer to TASK 20-60-00-370-814). (2) Inspect the main and nose: landing gears, wells, doors. (3) Apply or renew TEMPORARY PROTECTION TYPE II on all the structure sections, equipment supports and equipment. F. Pylons and nacelles (1) Remove the pylon lower access doors. NOTE: Most of the accesses are already removed through the "Z" check. (2) Check: all the lower and upper surface skin panels of each pylon, the lower and upper surface angle brackets for connection to the fuselage, the leading edges, the inspection doors and their frames, all the air inlets, the afterbody. (3) Inspect the internal structure of the pylons for corrosion. Page: 7 / 8
8. CLOSE UP WARNING: DO NOT PRESSURIZE HYDRAULIC SYSTEM 1 WITH MAIN LANDING GEAR DOOR(S) OPEN. IF YOU PRESSURIZE SYSTEM 1, THE DOOR(S) WILL CLOSE. THIS CAN CAUSE INJURY TO PERSONNEL AND/OR DAMAGE TO EQUIPMENT. A. Manually close the main landing gear doors (Refer to TASK 32-10-00-860-801). B. Remove the airbrake safeties (Refer to TASK 27-60-00-860-801, paragraph "Operation with airbrakes extended"). C. Remove the slat and flap safeties (Refer to TASK 27-50-00-860-802, paragraph "Operation on slats and/or flaps extended"). D. Remove the DANGER, DO NOT PRESSURIZE HYDRAULIC SYSTEMS placard. E. Energize the aircraft systems (Refer to TASK 24-00-00-860-801). F. Pressurize both hydraulic systems (Refer to TASK 29-00-00-860-801). G. Fully retract the airbrakes (Refer to TASK 27-60-00-860-801). H. Fully retract the flaps and slats (Refer to TASK 27-50-00-860-802). I. Cut off and drop the pressure in both hydraulic systems (Refer to TASK 29-00-00-860-801). J. De-energize the aircraft systems (Refer to TASK 24-00-00-860-801). K. Disconnect the hydraulic Ground Power Unit (GPU) (Refer to TASK 29-00-00-860-801). L. Disconnect the electrical Ground Power Unit (GPU) (Refer to TASK 24-00-00-860-801). Page: 8 / 8