Aviation Facilities and Support Structures CPC Knowledge Area

by Joseph C. Dean, P.E. and Steve Geusic, P.E., for the Director, Corrosion Policy & Oversight (DCPO), (DASD (Materiel Readiness))

Updated: 10-14-2021

INTRODUCTION

Within This Page

Introduction
Description
Additional Resources

Facilities that are located on aviation installations (i.e., bases, air stations, airfields, etc.) endure high impact and dynamic stresses due to operations and related demands. Those facilities may include hangars, runways, taxiways, pipelines and tanks for petroleum, oils, and lubricants (POL), wash racks, hush houses, and jet engine test cells. Supporting facilities include power distribution and conversion, barracks, administration buildings, sewage and water treatment, water distribution and sewage collection, roads, communication structures, and warehousing. Sub-structures include fencing, windows, doors (especially hangar doors), roofs, plumbing, heating, ventilation, and air conditioning.

Aviation Installations are located in a variety of different environments, each with their own unique impacts on materials degradation and corrosion. For instance, Aviation Installations located in coastal zones, with their inherently higher ESC, will likely exercise higher levels of corrosive deterioration. In these varied and ever-changing environments, designers and maintainers must be vigilant to ensure that the best materials, construction processes and sustainment practices are utilized. A facility’s design details must be selected with life-cycle effectiveness and durability considerations to ensure that the entire system of fixed and movable structures act as one to guarantee needed availability for the operating forces.

The Facilities Corrosion Impacts on Operations and Missions Table provides insights into how facilities categories can be impacted by corrosion. Environmental Severity Classifications (ESC) are described in UFC 1-200-01 DOD Building Code and further described in the ESC CPC Resource Page. The Corrosion Prevention and Control (CPC) efforts to keep an aviation facility located in ESC Zones 4 and 5 operationally ready are challenging and requires sound planning, design, construction, and sustainment efforts commensurate with those conditions. Photo 1 shows an aviation facility adjacent to a waterfront in Zone 5. All of these facilities are at high risk for accelerated corrosion impacts on operations and mission creating challenges for both sustainment and operations personnel.

photo of waterfront naval facilities and docks

Photo 1: Showing waterfront facilities and an airfield in top center.
Source: MC 1st Class Christopher B. Stoltz / U.S. Navy via Reuters file

The Whole Building Design Guide (WBDG) provides resources for designers, maintainers and facility managers that directly address broader issues for aviation facilities, including:

The Aviation page (includes information on Aircraft Maintenance Hangars, Paint Hangars, Jet Engine Test Cells (JETC), Corrosion Control Hangars (CCH) and Air Traffic Control Towers and Design Criteria Requirements, Design Criteria Requirements, Design Criteria Requirements.)
The Aviation Hangar page (provides information on hangar planning and design.)
Hangar Pavement Design (provides information on pavement design and examples)
Criteria (see the Relevant Codes and Standards Section at the end pf this page)

Naval Air Stations, Air Force Bases, Army Airfields, Reserve fields, and Coast Guard bases emulate small cities containing a broad combination of facility categories. This Knowledge Page will discuss the complexities of managing CPC across aviation-focused installations. Many DoD facilities are maintained by contracts; these contracts must include strong quality assurance (QA) and quality control (QC) programs. Contracts such as Design-Build, where the contractor hires the architect and engineer of record, must include criteria which will identify material selection guidance by ESC Zone and Cathodic Protection practices (e.g., design, installation and sustainment) in the Request for Proposal (RFP). See also the CPC Acquisition Issues Resource Page.

Description

Aviation facilities’ CPC, including supporting structures, requires the interaction of many engineering disciplines such as structural, electrical, environmental, mechanical, and civil and specialty engineering areas such as cathodic protection, geotechnical, material selection, and expertise in paints and coatings. Each discipline has an essential role to play in ensuring that aviation facilities are designed and constructed to be sustainable, especially those near waterfront locations.

The CPC related to planning and design of aviation facilities and supporting structures requires a thorough understanding of the many aspects of the area where they are constructed and associated design characteristics. These can include:

Environmental Severity Classification (ESC)
Sun exposure (ultraviolet [uV] radiation)
Salt-water impacts on materials and structures (depending on the proximity of the aviation facilities to salt-water and the coastal environment)
Geotechnical perspectives (e.g., soil support, corrosivity of chemicals and minerals residing in the soils)
Pressure sources (e.g., earthquakes, winds)
Friction and material interactions
Heat impacts from jet exhaust on ramps and runways
Foreign Object Damage (FOD) resulting from spalled concrete and deteriorated asphalt
Applications and usage of paints and coatings
Ponding (i.e., water accumulation without the ability to drain on materials susceptible to corrosion)
Cathodic protection system design and maintenance
Design geometry to prevent unnecessary corrosion situations (e.g., roof valleys allowing water access to building interiors, parapet wells, internal downspouts, dissimilar metal interaction, failure to provide proper barriers and insulation between corrosion materials)
Flight line support services (e.g., corrosive impacts on auxiliary power, water, fuel materials and distribution)
Selection of materials and coatings to achieve the required life-cycle and service requirements
Mitigation of the corrosivity of deicing chemicals, hydrocarbons such as fuels and lubricants, and fire-fighting foams

UFC 1-200-01 DoD Building Code, provides very specific guidance for design, construction and sustainment actions related to CPC. The UFC 1-200-01 Appendix ESC for DoD Locations, identifies the ESC Zone for each of the DoD Installations around the world, which then drives the selection of the types of materials and processes that should be used for corrosion-prone locations.

The CPC highlights from several of the most relevant UFC and UFGS documents for aviation facilities are provided below:

UFC 3-190-06 Protective Coatings and Paints: Provides requirements and technical guidance for the effective use of paint-type coatings to protect common materials such as metal, concrete, pavements, gypsum board and wooden structures at military activities from deterioration. This UFC applies to all Navy, Air Force, and Army service elements and contractors. Requires paints and coatings that are durable and minimize the need for preventative and corrective maintenance over the expected service life of the component or system. Note that this is a significant update from previous versions. Different materials will be used based on local environmental conditions (See UFC 1-200-01 DoD Building Code as required in the UFC). Corrosive environments, which require additional corrosion protection, are those project locations which have an Environmental Severity Classification (ESC) of C3, C4 or C5. Humid locations are those in ASHRAE climate zones 0A, 1A, 2A, 3A, 3C, 4C, and 5C (as identified in ASHRAE 90.1). Defines coating systems for specific uses. See Photo 5 for an example of the uV degradation of an organic coating system.
UFC 3-250-04 Standard Practice for Concrete Pavements: The UFC discusses the realities of the reaction of steel and de-icing salts and corrosion behavior when water is able to gain access. The use of coated dowels and reinforcing steel should be considered in the presence of seawater. Alkali-silica reactions as shown in Photo 2 are discussed in this UFC, which provides information on their risk, potential damage, and possible solutions. Much has transpired since this UFC was published, including extensive research into heat-resistant mix designs and the categorization and application of ESC Zones (see UFC 1-200-01).

Photo 2: Alkali-Silica Reaction in Concrete
Source: D, CPO

UFC 3-260-01 Airfield and Heliport Planning and Design: The UFC mentions corrosion control facilities, aircraft rinse facilities, and aircraft wash racks in the context of corrosion control. Those facilities require special attention to ensure operational integrity to both meet requirements and prevent environmental pollution.
UFC 3-260-02 Pavement Design for Airfields: The UFC provides an extensive description and discussion related to pavement joints and the associated need to establish and maintain joint integrity. Joint design and construction poses a serious risk factor related to CPC of pavements and the aircraft that utilize them. The UFC provides extensive guidance insights into pavement design, and while the word “corrosion” might not be used, the impact of failed subbase, water intrusion, erosion, concrete cracking allows access to steel reinforcing that causes spalling and foreign object damage (FOD). In sandy soils, where drainage structures are installed under ramps and pavements, the erosion of the subbase into the drainage structure through pipe joints allows the pavements to crack and fail as shown in Photos 3 and 4. The UFC also discusses alkali-silica aggregate reaction.

Photos 3 and 4: Runway asphalt deterioration examples.
Sources: (Left) Guy Choate, GARVER USA and (Right) Dwayne Page, Station Manager, WJLE News

UFC 3-270-01 O&M Manual: Asphalt and Concrete Pavement Maintenance and Repair: Mentions the hazards of using gypsum-based concrete (calcium sulfate) repair materials and the presence of free sulfates in the promotion of corrosion in reinforcing steel in pavements. Crack sealing can become a corrosion and FOD problem if not executed properly. Note also that UFC 1-200-01 update requires application of new corrosion and related environmental severity guidance and was published after this UFC.
UFC 3-570-01 Cathodic Protection: Delineates mandatory uses of Cathodic Protection (CP), many of which can be found at aviation installations. The UFC provides extensive information and guidance on which kinds of facilities would benefit from CP systems and what kinds of CP systems are appropriate for specific facilities.
UFC 3-570-06 Operation and Maintenance: Cathodic Protection Systems contains detailed procedures for sustaining CP Systems.

UV degradation of organic coating systems on roof

Photo 5: UV Degradation of Organic Coating Systems
Photo Source: D, CPO

UFC 3-600-01 Fire Protection Engineering for Facilities: Requires that above ground piping and embedded pipe utilized in fire-protection systems be corrosion-resistant (ASTM A312). For service mains and laterals, “provide appropriate corrosion protection based upon pipe materials and the corrosive properties of the water supply and earth.”
UFC 3-601-02 Operation and Maintenance: Inspection, Testing and Maintenance of Fire Protection Systems: Foam and Foam-Water Systems are discussed relative to maintenance and corrosion monitoring.
UFC 4-121-10N Design: Aircraft Fixed Point Utility Systems: Requires the use of UFC 1-200-01 which was recently updated to emphasize CPC and the corrosion risks in ESC Zones. Corrosion-resistant coatings and materials are mentioned.
UFC 4-133-01 Air Traffic Control and Air Operations Facilities: Addresses corrosion concerns and requirements for Control Cab Window Mullions), Catwalks, and Exterior Observation Grates.
UFC 4-171-01N Design: Aviation Training Facilities: Provides extensive guidance on corrosion control for finishes and materials. Specific design guidance is provided to address high-moisture impacts, to include ventilation (use corrosion-resistant materials in duct work), finishes and pool design. All components of the HVAC system should be made of corrosion-resistant materials. See the UFC for additional specific guidance.
UFC 4-211-01 Aircraft Maintenance Hangars: Discusses CPC and paint facilities. The coating requirements in the Protective Coatings section include guidance on painting all non-finished items such as exterior ferrous metals, hangar doors, interior ferrous metals related to primary and secondary steel framing inside Aircraft Maintenance Bays and fuel-resistant resinous flooring. The section on Sealed Concrete requires the use of sealers to prevent corrosion.
UFC 4-211-02 Aircraft Corrosion Control and Paint Facilities: "Provide(s) architects, engineers, and construction surveillance personnel with the essential, minimum requirements for the design and construction of Aircraft Corrosion Control or Paint Finishing Facilities." These types of facilities are focused on sustaining aircraft and are mentioned in this UFC to emphasize their operational importance. The UFC discusses CPC of the equipment side of installation operations, which include rinsing, stripping, and painting, and the chemical used in the stripping process can be corrosive to the facility infrastructure, containment, ventilation, and flooring systems.
UFC 4-212-01N Navy Engine Test Cells: Addresses the design criteria essential for the design and construction of Jet Engine Test Cells (JETC). See also the Table Inspection and Test Frequency.
UFGS 07 41 13 Metal Roof Panels: Discusses considerations for corrosion protection from chemical and uV radiation including primers, factory finishes, abrasion resistance, and surface protection from damage. It also discusses corrosion-resistant fasteners and miscellaneous metal framing, screws and rivets.
UFGS 07 61 14.00 20 Steel Standing Seam Roofing: Delineates corrosion resistant construction requirements for materials, warranties, closures and fasteners.
UFGS 08 34 16 Corrosion Control Hangar Doors: Delineates standards for hangar-door design and for the work experience of hangar-door manufacturers. This UFGS also explains installer requirements and discusses corrosion-resistant materials.
UFGS 09 90 00 Paints and Coatings addresses "requirements for painting of new and existing, interior and exterior substrates." Discusses corrosion and invokes UFC 1-200-01 DoD Building Code. Delineates ESC requirements for ESC Zones C3, C4 and C5 and ASHRAE 90.1 humid locations in climate zones) A, 1A, 2A, 3A, 4C and 5C. It includes contractor qualification requirements (SSPC QP 1, QP 2, etc.) and refers to SSPC, NACE, and MPI Standards. Topics include coatings, corrosion, rust, deterioration, mold, and mildew. See the Paints and Coatings Knowledge Area and the Coatings Modules in the WBDG Continuing Education Section. Many UFGSs for paints and coatings are listed at the end of this page including UFGS 09 96 00, UFGS 09 97 02, UFGS 09 97 13.00 40, UFGS 09 97 13.15, UFGS 09 97 13.16, UFGS 09 97 13.17, UFGS 09 97 13.27 (see below for links to these UFGS).
Cathodic Protection Specifications: This series of UFGSs includes extensive requirements to address corrosion protection of metallic structures through the use of CP. The requirements include description of the areas to be protected and the qualifications of the individuals to be involved in the design, supervision, testing and inspection the CP system. These UFGSs also define submittal requirements and describe CP by galvanic anodes, sacrificial anodes, and impressed current. Additional guidance is provided for steel water tanks. See also the CP Knowledge Page.
UFGS 26 56 20 Airfield and Heliport Lighting and Visual Navigation Aids: Section 1.6.6 Prevention of Corrosion states the requirement to protect metallic materials from corrosion. Aluminum should not be used in contact with earth or concrete, and aluminum conductors should not be used at all. Steel conduits installed underground must be protected from corrosion.
UFGS 32 13 13.43 High Temperature Concrete Paving for Airfields Using Lightweight and Traprock Aggregates discusses heat-resistant concrete-mix design for high-temperature-resistive pavements using lightweight and traprock aggregates. Also states mix design to mitigate alkali-silica aggregate reaction and sulfate attack.
UFGS 32 13 14.13 Concrete Paving for Airfields and Other Heavy Duty Pavements discusses alkali-silica reactivity aggregates, combinations of cementitious materials and concrete mix design.
UFGS 33 52 43.11 Aviation Fuel Mechanical Equipment provides important CPC requirements for various pieces of the aviation fuels system. Coating requirements are defined to include surface of tankage as well as connectors, valves, and mechanical equipment. Corrosion-resistant materials are to be used in components such as grounding straps and pump components.

Sustainment

CPC plays a significant role in aviation installation facility Sustainment, Restoration and Modernization (SRM) and Operations and Maintenance (O&M) of DoD installations. SRM and O&M are complimentary efforts that leverage good engineering practice and requirements identification to ensure that the CPC program is robust and consistent with ensuring that the installation and its facilities are operationally ready. In order to determine the best course of action, it is often essential to determine the cause and rate of corrosion. Specific areas of corrosion often visible on an aviation facility include:

POL storage and distribution
Airfield pavements
Water-tower coatings
Hangar doors and hardware
Fire protection piping and fittings
Metal roofs
Any metallic structure
Fencing
Elevated steam-line supports and aboveground utility systems
Swimming-pool enclosures (e.g., structure, surfaces, doors, windows) to include mold and mildew effects

It is relatively easy to resolve visible deterioration above ground, but more difficult to protect buried and hidden structures. If conduit steam lines are used, for example, the weak, more corrosion-prone areas of the utility should be monitored as part of a preventive-maintenance inspection program. Hangar-door tracks and mechanical works become problematic because of the immense weight impact on components that wears on coating protections.

While the criteria listed along with the discussion of locations is not all-inclusive, it does contain some insights into the magnitude of designing, constructing and sustainment of structures found on aviation installations in ESC Zones 1 through 5. Considering and addressing these issues will assist in achieving a corrosion-resistant design that supports mission effectiveness and meets life-cycle expectations.

Summary

The broad collection of Aviation Facility categories on an installation such as hangars, runways, roads, paved areas, administrative, barracks, dining, generation and distribution of utilities, waste and water treatment structures presents a challenge for the facility manager. Many facility categories are both visible and hidden from view, all of which are at risk of corrosive degradation. Some corrosion becomes immediately dangerous. If a concrete apron is not designed to handle the heat signature of aircraft in the inventory, it will degrade and result in a high potential for FOD potentially damaging the aircraft. Undiscovered underground-utility corrosion can result in loss of steam services. Petroleum-related system corrosion can produce a devastating series of events, including loss of product, suspension of operations, environmental violations, negative publicity, and heavy financial costs.

There are other CPC Source web pages addressing common issues such as fencing, doors, cathodic protection and pavements that relate to aviation facilities. Establishing and conducting a thorough maintenance management program that includes inspections, a recurring maintenance program, service calls, and related SRM actions, will provide confidence that corrosion-driven failures have been minimized. By conducting an active maintenance management program, SRM managers will be able to convey essential knowledge to designers and constructors to improve newly constructed and repaired facilities.

There is typically no single CPC criteria reference, so designers, constructors and sustainers often have to do research into multiple criteria and guidance documents to determine the best CPC approach. That effort will result in newly constructed or repaired facilities that meet durability and operational needs. Many of those resources are listed below.

Additional Resources

Unified Facilities Criteria (UFC)

Unified Facilities Guide Specifications (UFGS)

U.S. Army Corps of Engineers - Public Works Technical Bulletin (PWTB)

U.S. Naval Facilities Engineering Command

Interim Technical Guidance (ITG 2003-01) – Aircraft Maintenance Facility Design, 1 November 2002

Aviation Facilities and Support Structures CPC Knowledge Area