Appendix 1
32. Cotton, Flannel, CCC-C-458, Type II (plain weave, unbleached, napped both sides, 4.6 oz. weight) High lint, high absorbency, high wet strength, reusable after washing, and disposable. For use on cockpit indicator glass covers, plastic and acrylic control panels.
NOTE: Only authorized cloth for use in cleaning plastic and acrylics with solvents that have a flash point of less than 100 °F (38 °C).
SEALANTS
33. Adhesive-Sealant Silicone, Room Temperature Vulcanizing (RTV), Noncorrosive, 3145 RTV, MIL-A-46146, Type III For use on sensitive metals and avionics equipment.
Sealing areas where temperature is expected to be between 250 °F (121 °C) and 350 °F (177 °C).
34. Sealing Compound, Polysulfide, MIL-PRF-81733, Type I (Brush Application), Type II (Spatula Application) Contains corrosion inhibitors. For use in sealing gaps, seams, etc. For use up to 250 °F (121 °C).
35. Sealing Compound, SAE-AMS-S-83318 A quick-cure sealant that contains corrosion inhibitors.
For use in sealing gaps, seams, etc., during extreme cold weather activities.
36. Sealing Compound, Temperature-Resistant, Integral Fuel Tanks, SAE-AMS-S-8802, Type A, Class 2 (Brush Application) or Type B, Class 2 (Spatula Application) Sealing of gaps, seams, and faying surfaces. For use up to 250 °F (121 °C). Use when MIL-PRF-81733 is not available.
POTTING COMPOUNDS CAUTION: Potting Compounds Pro-Seal 777A/B (green) and EC-2273 (black) have experienced reversion to a liquid after 2 to 4 years of service depending on the environment. Not recommended for use in electrical connectors and avionics equipment.
37. Sealing Compound, Synthetic Rubber, Accelerated, MIL-PRF-8516 Class 1 (24 hr. cure) or Class 2 (48 hr. cure) or Class 3 (72 hr. cure) For sealing low voltage electrical connectors, wiring, and other electrical apparatus against moisture and corrosion where temperature will not exceed 200 °F (93 °C). Good resistance to gasoline, oils, grease, water, and humidity.
CAUTION: Not authorized for use in engine bays, keel areas, or areas adjacent to bleed air ducts.
38. Sealing Compound, Silicone Rubber, Room Temperature RTV, MIL-S-23586, Type II, Class 2, Grade A For sealing small electrical connectors in well-ventilated areas where the operating temperature normally exceeds 200 °F (93 °C), but does not exceed 450 °F (232 °C). Good resistance to weathering and moisture, and withstands ozone.
CAUTION: Restricted to well-ventilated areas due to volatile cure.
Appendix 1
39. Sealing Compound, Silicone Rubber, RTV, MIL-S-23586, Type I, Class 1, Grade B-1 For sealing or encasement of electrical connectors and electronic components where the operating temperature normally exceeds 200 °F (93 °C), but does not exceed 450 °F (232 °C). Good resistance to weathering and moisture, and withstands ozone.
NOTE: Does not contain cure volatiles as MIL-S-23586, Type II, Class 2, Grade A.
MASKING MATERIALS AND TAPES
40. Preservation and Sealing Tape, Pressure Sensitive Adhesive, MIL-T-22085, Type II For holding barrier material in place during shipping.
Treated, noncorrosive, non-fungus supporting. For use on equipment without overcoating.
41. Tape, Pressure Sensitive Adhesive, Paper Masking, Non-staining, MIL-T-21595, Type I For masking of undamaged areas during paint touch-up on equipment cases, covers, mounting racks, etc. For masking electrical and electronic components during replacement of conformal coatings and varnishing.
CAUTION: Use only if component is sufficiently rigid to withstand application and removal of tape.
42. Tape, Pressure Sensitive Adhesive, MIL-T-23397, Type II For masking during paint stripping operations on avionics equipment and airframe structure.
43. Tape, Pressure Sensitive, MIL-T-23142 For isolating dissimilar metals where galvanic action may take place in avionics equipment.
44. Insulating Tape Electrical, Self Bonding, Silicone Used to wrap electrical wire bundles and connectors exposed to harsh environments.
45. Paper, Kraft, Untreated, Wrapping, UU-P-268 Protection of surrounding areas during paint spray operations. General-use masking.
CONFORMAL COATINGS NOTE: Materials listed are for general purpose use on conformal coated circuit boards. For special applications on highly critical components, refer to the OEM’s maintenance manual.
46. Epoxy Coating, Two-Part Application For coating and patching epoxy- and parylene-coated circuit boards and components.
47. Polyurethane Coating (Brush Application) For coating and patching polyurethane and varnish coated circuit boards and components.
48. RTV Coating, Nonflowable (Brush Application), 738 RTV (White) MIL-A-46146, Type I For coating and patching RTV coated circuit boards and components.
NOTE: Will not flow into crevices or other hard to reach places.
49. RTV Coating, Flowable (Brush Application), 3140 RTV (Clear) MIL-A-46146, Type III For coating and patching RTV coated circuit boards and components.
NOTE: Use in applications where a flowable material is required, such as potting connectors.
50. Acrylic Coating For coating and patching of acrylic and lacquer coated circuit boards and components.
Appendix 1
51. Varnish, MIL-V-173C Moisture and fungus resistant for electrical equipment and for clear coating on copper. For coating and patching of varnish coated circuit boards.
NOTE: Thinner: see Item No. 18.
NEUTRALIZING AGENTS
52. Sodium Bicarbonate, Technical, O-S-576 For neutralizing spilled sulfuric acid (electrolyte) in lead acid battery installations. For neutralizing leaking tantalum capacitors in avionics equipment.
53. Sodium Phosphate, Monobasic, Anhydrous, Technical, AWWA B504-18 For neutralizing spilled potassium hydroxide (electrolyte) in nickel-cadmium and silver-zinc battery installations. Also used as an abrasive material in miniabrasive cleaning units.
CHEMICAL CONVERSION COATINGS
54. Boric Acid, A-A-59282 For neutralizing electrolyte leakage from nickel-cadmium batteries.
55. Chemical Conversion Material for Coating Aluminum and Aluminum Alloys, MIL-DTL-81706, Class 1A or Class 3 Used to conversion coat bare aluminum. Class 1: used for general conversion coating of aluminum. Class 3:
used for conversion coating of aluminum where lower electrical resistance is required.
56. Chemical Conversion Material for Coating Magnesium Alloys, SAE-AMS-M-3171, Type VI Used to conversion coat bare magnesium.
PAINT, PRIMERS, AND STRIPPERS
57. Epoxy Primer, Water Reducible, MIL-P-85582, Class II, Class I Covers low-moisture sensitivity, corrosion-inhibited primer. Intended for spray application on surface treated metal. Low Volatile Organic Compound (VOC).
58. Primer Coating, Epoxy Polyamide, MIL-P-23377, Type II Covers low-moisture sensitivity, corrosion-inhibited primer. Intended for spray application on surface treated metal.
59. Lacquer, Acrylic Nitrocellulose, MIL-L-19538C (Lusterless) Used for cockpit instrument, control box, and avionics box touch-up. For equipment markings.
60. Coating, Epoxy-Polyamide, MIL-C-22750 Used as a topcoat on all avionics equipment.
NOTE: Mix only materials from the same kit (the brand and batch numbers on the pigmented compound can must be the same as those on the converter can).
61. Coating, Urethane, Aliphatic, Isocyanate, MIL-C-83286B Used as a topcoat on all avionics equipment. Touch-up of polyurethane paint systems. (Noncompliant.)
62. Coating, Aliphatic Polyurethane, Single Component, MIL-C-53039 Used as a topcoat on all avionics equipment.
63. Coating, Polyurethane High Solids, MIL-PRF-85285, Type I and Type II Type I used as a topcoat on all avionics equipment.
420 grams/liter maximum VOC.
Appendix 1 Type II used as a preferred topcoat for ground support equipment. 340 grams/liter maximum VOC.
64. Coating Compound, Bituminous Solvent Type, Black, MIL-C-450, Low Solids Spraying Consistency or Medium Solids Brush and Spray Consistency Petroleum asphalt base. Excellent acid resistance. For use on wood or metal battery boxes. Drying time: 30 to 60 minutes.
NOTE: Thinner: Petroleum Spirits, TT-T-291, Item No. 18.
65. Epoxy Paint Remover, QPL-81294 Removal of paint finishes.
66. Polyethylene Foam, PPP-C-1752, Type II 1/2" x 4' x 125', in rolls For cushioning equipment and protection against shock, on shelves, work benches, pallets, etc.
NOTE: Use double layers for heavy equipment.
PACKAGING MATERIALS
67. Cushioning Material, Plastic Open Cell, PPP-C-1842, Type III, Style A;
Type III, Style B;
Width 12", 24", and 48" in rolls To protect ESD-sensitive items from damage due to shock, vibration, corrosion, and abrasion during handling and shipment.
68. Cushioning Material, Cellular Plastic Film (Bubble Wrap), PPP-C-795, Class 1 or Class 3 Width 12", 24", and 48" in rolls For cushioning equipment and protection against shock.
Provides limited protection against moisture. Seal with pressure-sensitive tape, MIL-T-22085, Item No. 40.
69. Unicellular Polypropylene Packaging Foam, PPP-C-1797 Width 12", 24", and 48" in rolls Lint-free, non-dusting, nonabrasive. For cushioning equipment and protection against shock. Provides protection against moisture. Use in conjunction with Barrier Material, Water Vapor Proof, MIL-B-131, Item No. 72. Seal with pressure-sensitive tape, MIL-T-22085, Item No. 40.
70. Bags, Plastic (General Purpose), PPP-B-26 For protecting miniature and microminiature circuit components and laminated circuit boards against moisture and contamination. Considered for short-term, temporary protection during maintenance operation.
71. Barrier Material, Water Vapor proof, Greaseproof, Flexible, Heat-Sealable, MIL-B-131, Class 1, 48" x 200 yd. roll For protecting miniature and microminiature circuit components and laminated circuit boards against moisture and contamination. Heat-sealable. Protects material during transportation, storage, and in all weather conditions.
72. Barrier Material, Water Vapor proof, Protective, Electrostatic and Electromagnetic Shielding, MIL-B-81705, Type I Provides ESD and electromagnetic interference (EMI) packaging protection for hardware and components.
May be used for long or short-term protection. Can be heat-sealed.
73. Barrier Material, Water Vapor proof, Protective, Electrostatic and Electromagnetic Static Dissipative, MIL-B-81705, Type II Provides ESD and EMI packaging protection for hardware and components. May be used for long or short-term protection. Can be heat-sealed.
Appendix 1
TRACERS
74. Indicator, Thymol Blue Reagent, MIL-T-17412 For detecting reverse voltage damage to wet-slug tantalum capacitors. Also used as a Nicad electrolyte indicator.
75. Desiccant, Bagged, MIL-D-3464, Grade A Absorbs moisture, lowers relative humidity when sealed in container.
76. Humidity Indicator, MS-20003 Used to determine that desiccant within a package is sufficiently active to maintain a relative humidity below that at which corrosion will occur.
77. Water, Distilled Used for cleaning in critical soldering operations.
78. Ammonium Hydroxide, Technical, O-A-451 Used to assist in dissolving indicator, Thymol Blue Reagent, A-A-59282.
79. Glass Beads, MIL-G-9954 Used as abrasive in handheld tool in blast cleaning cabinet.
80. Silver Nitrate, A-A-59282 Used to identify magnesium metal.
81. Silver Nitrate, Solution, MIL-W-535 Used to identify magnesium metal.
Appendix 2 APPENDIX 2. SPECIFIC CONSUMABLE MATERIALS FOR CLEANING AND
CORROSION PREVENTION AND CONTROL
2-1. INTRODUCTION AND SCOPE.
This appendix supplements Appendix 1 by providing a more detailed listing of selected products by product numbers (P/N) and manufacturer(s) of acceptable consumable materials for avionics cleaning and corrosion prevention and control. Table 2-1 provides product numbers and manufacturer’s name. Table 2-2 provides a listing of the manufacturers and addresses of their main plants.
Table Grouping Page(s) 2-1 Cleaning Compounds…………………………………………1 Corrosion Preventive Compounds………………………….1-2 Sealants……………………………………………………..2-3 2-1 2-1 TABLE 2-1. AVIONICS CLEANING AND CORROSION REMOVAL CONSUMABLE
MATERIALS ITEM NO. PRODUCT TYPE MANUFACTURER’S
DESIGNATION CLEANING COMPOUND, MIL-PRF-85570 9 Type II Leeder 1140-F 9 Type II 8505 9 Type II Calla 855 9 Type II Aerowash NV 9 Type II AC-17 8 9 Type II ED-4 10 9 Type II EZE-445 9 Type II MA-102 9 Type II CeeBee R-682 9 Type II 8002-2-SD 9 Type II Octagon 855702 9 Type II LD-38 9 Type II PENN AIR M5572B 9 Type II 93-1 9 Type II Turco 6692 CORROSION PREVENTIVE COMPOUND, MIL-PRF-81309, Class 1 (Bulk), Class 2 (Aerosol) 20 Type III 2080-MLCO 20 Type III So-Sure 0964-000 20 Type III LPS-814A 20 Type III 22028C2-3 20 Type III Ardrox 3205 Aerosol
Appendix 2 ITEM NO. PRODUCT TYPE MANUFACTURER’S
DESIGNATION 20 Type III CRC 3-36 20 Type III ACF-50 Aerosol 21 Type II Class 1 Alox 2028C 21 Type II Class 1 Aidchim Alox 2080 21 Type II Class 1 2028 BC-BULK 21 Type II Class 1 Nox Rust 212 21 Type II Class 1 2775 21 Type II Class 1 So-Sure 813 21 Type II Class 1 LPS-813 Bulk 21 Type II Class 1 Octoil 5068 21 Type II Class 1 Omni 4150A 21 Type II Class 1 97-SX092 21 Type II Class 1 22018CM-Bulk 21 Type II Class 1 Ardrox 3204 21 Type II Class 1 BATCO Rust Preventive 21 Type II Class 1 706 P.D.R.P. Bulk 21 Type II Class 1 D-5026 Bulk 21 Type II Class 1 Ardrox 3204 Aerosol 21 Type II Class 2 2028-BCCO Bulk 21 Type II Class 2 So-Sure 0954-000 21 Type II Class 2 LPS-813A 21 Type II Class 2 706 P.D.R.P 21 Type II Class 2 22028C2 CORROSION PREVENTIVE COMPOUND, MIL-PRF-16173 23 Grade 4 TECTYL 846 23 Grade 4 846-BC 23 Grade 4 Braycote 194 23 Grade 4 CONVOY 734 23 Grade 4 Nox-Rust X-110 23 Grade 4 F & L 5846 23 Grade 4 Steelgard MS-31 23 Grade 4 Poly Oleum 5000 23 Grade 4 ST 1846 23 Grade 4 No-Rust X-10 SEALANTS MIL-PRF-81733, Type I (Brush Application), Type II (Spatula Application) NOTE: Dash number following Type gives working time of the sealant in hours.
34 Type I-1/2 P/S 870 A-1/2 34 Type I-1/2 PR 1440G A-1/2 34 Type I-2 P/S 870 A-2 34 Type I-2 PR 1440G A-2 34 Type II-1/2 P/S 870 B-1/2 34 Type II-1/2 PR 1440G B-1/2
Appendix 2 ITEM NO. PRODUCT TYPE MANUFACTURER’S
DESIGNATION 34 Type II-2 P/S 870 B-2 34 Type II-2 PR 1440G B-2 34 Type II-2 PR 1436G B-2 34 Type II-4 P/S 870 B-4 34 Type II-4 PR 1440G B-4 SEALANTS SAE-AMS-S-8802, Class A (Brush Application), Class B (Spatula Application) NOTE: Dash number following Class gives working time of the sealant in hours.
36 Class A-1/2 PR-1422 36 Class A-2 36 Class B-1/2 36 Class B-1 36 Class B-2 36 Class B-2 BR 4005 36 Class B-1/2 FR 1072 36 Class B-2 36 Class A-1/2 CS-3204 36 Class A-1 36 Class A-2 36 Class B-1/2 36 Class B-1 36 Class B-2 36 Class B-1 WS-8020 36 Class B-2 36 Class B-4 36 Class B-1/2 MC-236 36 Class B-1 36 Class B-2 36 Class B-2 PR-1440 36 Class A-1/2 PR-1440 36 Class A-1 PR-1440 36 Class A-2 Pro-Seal 890 36 Class A-2 PR-1440 36 Class B-1/2 Pro-Seal 890 36 Class B-1/2 PR-1440 36 Class B-1 PR-1440 36 Class B-2 Pro-Seal 890 36 Class B-2 PR-1440 36 Class B-4 Pro-Seal 890 36 Class B-4 PR-1440
Appendix 3 APPENDIX 3. DEFINITION OF TERMS Acetic Acid An organic acid that can form when a microorganism (acetobacteraceti) reacts with ethyl alcohol in the presence of oxygen. Characteristic of vinegar.
Acidic Acid forming or having acid characteristics.
Active Metal A metal ready to corrode or being corroded.
Additive A compound added for a particular purpose. For example, additives in fuel and lubricants can prevent corrosion, gum formation, varnishing, sludge formation, and knocking.
Aerobic A process which is incapable of occurring in the absence of oxygen.
Alkaline Having a pH greater than 7.
Alloy A combination of two or more metals.
Anaerobic A process which is capable of occurring in the absence of oxygen.
Anion A negatively charged ion of an electrolyte which migrates toward the anode. The chloride in sea water is an anion.
Anode The electrode of a corrosion cell at which oxidation or corrosion occurs. It may be a small area on the surface of a metal or alloy, such as that where a pit develops, or it may be the more active metal in a cell composed of two dissimilar metals, (i.e., the one with the greater tendency to go into solution). The corrosion process involves the change of metal atoms into actions with a liberation of electrons that migrate through the metal to the cathode of the cell.
Anodize Application of a protective oxide film on a metal (such as aluminum) through an electrolytic process. This layer provides protection from corrosion and is a good base for paint.
Aqueous Made from, with, or by water.
Appendix 3 Austenitic A term applied to that condition of iron associated with a change in crystal structure that makes it nonmagnetic. This occurs with ordinary iron at an elevated temperature. When sufficient chromium and nickel are present, lead becomes austenitic (nonmagnetic) at atmospheric temperatures. This is the case with many stainless steels that combine about 18% chromium and 8% or more nickel.
Bilge The lowest point of an aircraft’s inner hull. This is the area where cable runs, wire bundles, and coaxial cables are routed, and lights and antennas are often mounted.
Capillary Action The action by which the surface of a liquid in contact with a solid is advanced or retarded (raised or lowered). This is caused by the relative attraction of the liquid molecules to each other (surface tension) and those of the solid. The wicking of fluid up a cloth is an example of capillary action.
Carbonize To convert into carbon residue, usually by high heat.
Cathode The less-active electrode of a corrosion cell, where the action of the corrosion current causes a reduction reaction.
Cation A positively charged ion of an electrolyte which migrates toward the cathode. Metal ions, such as iron or copper, are cations.
Caustic Embrittlement The result of the combined action of tensile stress and corrosion in an alkaline solution. This can occur in riveted lap joints where there is a concentration of an alkali solution.
Cell In the corrosion process, a cell is a source of an electrical current that is responsible for the corrosion. It consists of an anode and a cathode immersed in an electrolyte and electrically joined together. The anode and cathode may be separate metals or dissimilar areas on the same metal.
Chemical Conversion Coating A chemical treatment of a metal surface, such as aluminum or magnesium, which results in a protective (corrosion resistant) film on the metal’s surface. The coating also greatly enhances paint adhesion.
Chloride A compound of chlorine. Many varieties of this compound are present in seawater and contribute to making the seawater an electrolyte (electrical conductive).
Clear Water Colorless water containing no visible suspended particles.
Appendix 3 Compound Substances containing two or more elements.
Concentration Cell An electrolytic cell, consisting of an electrolyte and two electrodes of the same metal or alloy, that develops a difference in potential as a result of a difference in concentration of ions (most often metal ions) or oxygen at different points in the solution.
Conformal Coating A closely adhering moisture and gas barrier applied to circuit boards to prevent corrosion and breakdown of electrical insulation.
Corona A faint glow adjacent to the surface of an electrical conductor at high voltage.
Corrosion The deterioration of a substance (usually a metal) because of a reaction with its environment.
Corrosion Fatigue A reduction in the ability of a metal to withstand cyclic stress by its exposure to a corrosive environment.
Corrosion Rate The speed or rate of a corrosion attack expressed in material weight loss per unit of time.
Couple Two or more metals or alloys in electrical contact with each other. These usually act as the electrodes of a cell if they are immersed in an electrolyte.
Critical Avionics Components Miniature or microminiature circuits including the components, printed circuit boards, tunable coils, tuned circuits, and devices with gold- or silver-plated connectors or contacts.
Critical Humidity The relative humidity, under a specific set of conditions, at which a metal or an alloy will begin to corrode. In the presence of hygroscopic (moisture-absorptive) solids or corrosion products, the critical humidity will be lowered. For example, steel will not corrode if the relative humidity is less than 30 percent in a marine atmosphere.
Deionized Water Water which has had various minerals and inorganic materials removed by means of an ion exchange process.
Desiccant A drying agent which acts by absorbing moisture.
Appendix 3 Distilled Water Water which has various organic and inorganic materials removed by means of an evaporation and condensation (distillation) process.
Durability Ability of avionics equipment or components to function and sustain stress in field service for a specific period of time with economical maintenance. The durability is measured in terms of minimum acceptable failure free lifetime (MFL) and expected maximum lifetime (EML), including repairs.
Elastomer A synthetic material with elastic properties.
Electrode A metal or alloy that is in contact with an electrolyte and serves as the site where electricity passes in either direction between the electrolyte and metal. The current in the electrode itself is a flow of electrons, whereas, in the electrolyte ions carry electrical charges, and it is their orderly movement in solution which constitutes a flow of current in the electrolyte.
Electrolyte Any substance which, in solution or fused, exists as electrically charged ions that render the liquid capable of conducting a current. Soluble acids, bases, and salts, such as those in seawater, are electrolytes.
Element Substances which cannot be decomposed by ordinary chemical changes or made by these changes.
Embrittlement Severe loss of ductility of a metal alloy.
Emulsified One liquid dispersed throughout another liquid with which it will not mix to form a homogeneous solution.
Encapsulant The general term describing materials used to envelop or fill a void to prevent the entrance of moisture or fungus. Conformal coatings, fungus-proof coatings, and potting compounds are all forms of encapsulants.
Ester/Diester Oils Oils containing synthetic materials known as esters or diesters, which are chemically formed by the reaction of an alcohol and an acid. These synthetic oils can attack certain plastics and paints.
Exfoliation The breaking away of a material from its surface in flakes or layers. A thick layer-like growth of corrosion products.