Compressor Washing for Phenoms 100 and 300

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Embraer Phenom 100 & 300 - Compressor Washing Recommendations Prepared by Luis Colarino – February 2011 Page 1 of 10 Introduction: Corrosion is and has always been a serious issue for all types of airplanes. Through the recent years, several inspection programs, procedures, and materials have been developed to keep corrosion as far away as possible from airplane components and structures. Corrosion is the electrochemical deterioration of a metal or composite structure caused by its chemical reaction with the surrounding environment. While new and better materials are continuously being developed, this process is offset, in part, by a more aggressive operational environment which makes corrosion a complex phenomenom. It can take many different forms and the resistance of aircraft materials to corrosion can drastically change with only a small environmental change. Within this scenario, “prevention” is the key. In this article, the focus will be in the environment, that is, the geographical locations of the globe and the respective effect that they can have on airplanes in terms of corrosion. The main objective is to present the basics behind the current preventive recommendations contained in the Maintenance Manuals, more specifically in terms of engine compressor washing schedules. Most of the article was based in the FAA AC (Advisory Circular) 43-4A “Corrosion Control For Aircraft” which was published in 1991 and contains a large amount of data regarding identification and treatment of corrosive attack on aircraft structure and engine materials. Discussion: Following paragraphs were extract from the AC 43-4A: Paragraph 411 Factors in Corrosion Control: d. Geographical Location and Environment. This factor concerns systems exposed to marine atmospheres, moisture, acid rain, tropical temperature conditions, industrial chemicals, and soils and dust in the atmosphere. Limit, whenever possible, the requirement for operation of aircraft in adverse environments. (1) Moisture is present in the air as a gas (water vapor) or as finely divided droplets of liquid (mist or fog) and often contains contaminants such as chlorides, sulfates and nitrates, which increase its corrosive effects. Condensed moisture which evaporates will leave its contaminants behind. Condensed moisture and its contaminants can also be trapped in close fitting, wettable joints, such as faying surfaces and be drawn along poor band lines by capilarity action. (2) Salt particles, when dissolved in water, form strong electrolytes. Normal sea winds carry dissolved salt which makes coastal environments highly corrosive. (3) Industrial Poluants (such as carbon, nitrates, ozone, sulfur dioxide and sulfates) contribute to the deterioration of nonmetallic materials and can cause severe corrosion of metals. (4) Warm moist air, normally found in tropical climates accelerates corrosion while cold dry air normally found in artic climates reduces corrosion. Embraer Phenom 100 & 300 - Compressor Washing Recommendations Prepared by Luis Colarino – February 2011 Page 2 of 10 Paragraph 412 Preventative Maintenance: a. Prevention. Corrosion prevention of aircraft structure depends on a comprehensive corrosio prevention and control plan, implemented from the start of operation of an aircraft, which includes: (1) Adequately trained personnel in: i. Recognition of corrosion inducing conditions ii. Corrosion identification techniques iii. Corrosion detection, cleaning and treating, and iv. Lubrication and preservation of aircraft structure and components (2) Inspection for corrosion on a scheduled basis. (3) Through cleaning, inspection, lubrication and preservation at prescribed intervals. Suggested intervals based on operating environment (see figures 4-15 through 4-20) are: i. Mild zones: Every 90 days ii. Moderate zones: Every 45 days iii. Severe zones: Every 15 days (4) Prompt corrosion treatment after detection. (5) Accurate record keeping and reporting of material or design deficiencies to the manufacturer and the FAA. (6) Use of appropriate materials, equipment and technical publications. (7) Maintenance of the basic finish systems. (8) Keeping drain holes and passages open and functional. Sealants, leveling compounds, miscelaneous debris or corrosion inhibitors should not block drain paths. (9) Replacing deteriorated or damaged gaskets and sealants (using non-corrosive type sealants) to avoid water intrusion and entrapment which leads to corrosion. (10) Minimizing the exposure of aircraft to adverse environments, such as hangaring away from salt spray. Embraer Phenom 100 & 300 - Compressor Washing Recommendations Prepared by Luis Colarino – February 2011 Page 3 of 10 Figure 4-15: North America Corrosion Severity Map Embraer Phenom 100 & 300 - Compressor Washing Recommendations Prepared by Luis Colarino – February 2011 Page 4 of 10 Figure 4-16: South America Corrosion Severity Map Embraer Phenom 100 & 300 - Compressor Washing Recommendations Prepared by Luis Colarino – February 2011 Page 5 of 10 Figure 4-17: Africa Corrosion Severity Map Embraer Phenom 100 & 300 - Compressor Washing Recommendations Prepared by Luis Colarino – February 2011 Page 6 of 10 Figure 4-18: South Pacific Corrosion Severity Map Embraer Phenom 100 & 300 - Compressor Washing Recommendations Prepared by Luis Colarino – February 2011 Page 7 of 10 Figure 4-19: Asia Corrosion Severity Map Embraer Phenom 100 & 300 - Compressor Washing Recommendations Prepared by Luis Colarino – February 2011 Page 8 of 10 Figure 4-20: Europe and Asia Minor Corrosion Severity Map Embraer Phenom 100 & 300 - Compressor Washing Recommendations Prepared by Luis Colarino – February 2011 Page 9 of 10 Recommendations: Information extracted from PW617F and PW515E Engine Maintenance Manuals Section 05-20-00: The manual section contains information related to the scheduled maintenance checks which include the following Compressor Wash Schedules: Phenom 100 CONDITION INSPECTION/TASK INTERVAL