Members of AFRL's Air Force Corrosion Prevention and Control Office (AFCPCO) teamed with corrosion experts from Warner Robins Air Logistics Center to assess environmentally induced damage to systems and equipment subjected to extended operations in Southwest Asia (SWA). The purpose of the ongoing assessment effort is to observe the effects of sand and dust intrusion on Air Force (AF) weapons systems and sensitive support equipment (see figure), analyze sands from various locations, and compare corrosion prevention and control policies and inspection requirements from prewar to present-day operations. As the investigation proceeds, team members are providing progressive and alternative approaches to corrosion prevention and control, wet and dry cleaning, and aircraft maintenance tasks performed in rigorous environmental conditions.
The AFCPCO has a legacy of anticipating, managing, and resolving corrosion-related problems; developing and evaluating new repair, maintenance, and corrosion suppression technologies and techniques; and reducing the environmental severity, cost, and impact of corrosion prevention.1 The group's field-level support efforts will ultimately improve the readiness, cost, and structural integrity of AF systems and equipment operating in SWA and similarly harsh desert climates.
Since Operation DESERT SHIELD in 1990, the AF has continued to operate extensively in a desert environment. These extended desert operations have resulted in the substantial intrusion of very fine sand and dust into aircraft, weapons systems, support equipment, and communications/ electronic equipment. The degree of this environmentally inflicted intrusion extends beyond what modern AF systems and equipment have previously experienced. Basically, the abrasive properties of the sand and dust are causing premature parts replacement due to wear. In fact, random sampling of contaminated equipment reveals high levels of corrosive anions, which accelerate the rate of corrosion in a wide variety of materials.
In response, the AFCPCO team is performing in-depth analysis in the areas of corrosion, erosion, and dust intrusion; corrosion prevention and control policies; the use of corrosion prevention compounds (CPC); the effectiveness and frequency of wash cycles; and cleaning methods. During its research, the team observed that soft-film CPCs allowed contaminants to adhere to surfaces, a condition that could impair the CPC's effectiveness. Consequently, the researchers determined that hard-film coatings may be more effective as temporary coating replacements for nonmoving parts. The team subsequently provided recommendations involving cleaning equipment and the reapplication of CPCs in a sheltered environment instead of an open area. The researchers also offered advice regarding more frequent cleaning cycles, including both the removal and reapplication of coatings and the removal of excess coatings.
The team's assessment also indicated an initial lack of aircraft exterior washing and clear-water rinse cycles in specific SWA forward areas. Additionally, the team noticed that technicians were generally not cleaning an aircraft's interior surfaces until the asset returned to its home station. Despite poor water quality, a lack of adequate wash facilities and equipment, and an increased operational tempo, the proper removal of dust and grit contamination is nonetheless imperative to preventing corrosion, insulation erosion, air filter clogging, electrical switch and circuit breaker binding, and a variety of other adverse effects.
The assessment team therefore identified several alternative cleaning options. The researchers stressed the need for increasing water purification efforts and identified wash rack capabilities. In addition, they suggested methods for drycleaning interior recesses with vacuums, soft bristle brushes, and other approved cleaning devices. The researchers also suggested rotating the equipment to in-country bases with adequate corrosion control facilities. The AFCPCO team is now in the process of modifying current technical orders to improve corrosion and erosion prevention efforts in desert environments.
The team intends to use its assessment results to ensure that the AF has the best available materials and costeffective methods for improving the corrosion protection of systems and materials while maintaining environmental compliance. To date, the AFCPCO has already provided SWAdeployed units with effective sealants, sealing tapes, electrical protection, and gel-type gasket materials. All of these on-the-spot solutions have successfully addressed critical equipment operation challenges, thus reestablishing their effectiveness in the desert environment.
Ms. Kimberly T. Andrews, Mr. David Ellicks, Mr. Frederick Johnson, and Mr. Timothy Anderl (General Dynamics), of the Air Force Research Laboratory's Materials and Manufacturing Directorate, wrote this article. For more information visit http://www.afrl.af.mil/techconn_index.asp. Reference document ML-H-05-31.
1 Anderl, T. and Bullock, D. "Air Force Corrosion Prevention and Control Office." AFRL Technology Horizons®, vol 5, no 1 (Feb 04): 50-51. http://www.afrlhorizons.com/ Briefs/Feb04/ML0302.html.
Air Force Research Laboratory Technology Horizons Magazine
This article first appeared in the December, 2006 issue of Air Force Research Laboratory Technology Horizons Magazine.
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