The CTMA Connector May 2001

Welcome to The CTMA Connector, a monthly newsletter designed to provide news and ideas about the Commercial Technologies for Maintenance Activities (CTMA) program. The CTMA program is a joint Department of Defense/National Center for Manufacturing Sciences (DoD/NCMS) effort promoting collaborative technology development between industry and the DoD maintenance and repair facilities. This newsletter will give you selected highlights of ongoing projects, serve as a forum for promoting new project ideas, and share other news of interest to the program. Our goal is to stimulate your participation and solicit your input. Feel free to submit items for the newsletter as well as any suggestions to make it more useful.

Plan to be in Hilton Head, South Carolina, on Tuesday, May 8, for the 2nd Annual CTMA Program Symposium. Held in conjunction with the NCMS Spring Conference, the symposium will include presentations showcasing active projects, identifying DoD needs, and promoting new ideas. In addition, there will be three focused workshops in telemaintenance, solid freeform fabrication, and laser shock peening. The workshops will bring together other programs within the DoD, as well as other federal agencies sponsoring projects in these three areas, to share information and to better coordinate our activities.

If you wish to participate in the afternoon presentations or would like more information, contact Chuck Ryan. The government room rate of $99 expires on April 10. To ensure availability at this rate, make your reservation by contacting the Hilton Head Marriott Resort directly at 800-228-9290 or 843-686-8400 and mention NCMS. To register for the event, sign up on the CTMA website. For those arriving on Monday evening, you can also sign up for dinner and entertainment by the Capitol Steps. For more information contact Beth Bolog at 734-995-7962.

The Oklahoma City Air Logistics Center needed a box cover for an E-3 aircraft overhead air-cooling unit. A good candidate for building via rapid prototyping, the cover was quickly made on an FDM machine by project participant United Technologies, and sent to OC-ALC. The part was lightly sanded and sealed with a clear Krylon acrylic spray, and is now being used directly in the aircraft. There is no need to make a mold for future parts, thus greatly reducing time and avoiding added costs. In addition, the part has material properties preferred to those found in a part molded by conventional techniques.

Several projects ideas have been recently submitted through the Joint Depot Maintenance Activities Group (JDMAG). If you are interested in any of the following, please contact Chuck Ryan.

In-service honeycomb parts on U.S. Navy aircraft are degrading much sooner than expected from a number of different types of energy. These types of energy consist of impact damage, heat damage, maintenance induced prying damage, and corrosion damage to the aluminum honeycomb cores. NADEP CP has had to deal with chromate treated core problems on H-1, H-46, H-53 and H-60B rotorcraft. The ramp on the H-46 requires 300 man-hours for repair and is in need of constant attention. Replacement of this part is prohibitively high ($3M for 10 parts) because of non-availability of tooling. The H-53 work platform door is another high maintenance component needing 80 man-hours per repair. The main cabin door of the H-60B can have as little as 25% of the total 17 ft²of conventional core corroded and still require component replacement at $34,000 a copy. NADEP CP has recently proposed replacement of existing aluminum core with PAA aluminum core for floorboards for existing H-1 helicopters experiencing corrosion related problems and for H-1 upgrade aircraft.

NADEP Jacksonville recently requested approval from the Naval Air System Command (NAVAIR) for use of PAA aluminum core to address extensive EA-6B degradation of conventional aluminum honeycomb core. Rudders, inboard slats and outboard flaps are some of the control surface parts of this aircraft requiring rework and/or replacement. Total maintenance costs for these three parts alone are estimated to be $3.4M per annum. Core around fasteners in inlet walls of F-14 aircraft requires frequent refurbishment and replacement at NADEP Jacksonville.

Wiring is a complex system that includes insulated power and signal conductors, fiber optics, connectors, protection devices (circuit breakers, current limiters and fuses), and power distribution and control components. The wiring system performs vital functions such as electrical power, control signal and information distribution throughout an aerospace vehicle. The aerospace wiring system is the infrastructure linking electrical, electromechanical and avionics subsystems. Wiring has emerged as a critical safety-of-flight system because of the increasing complexity, high density, and critical interface between electrical and electronic sub-systems.

The aging effects experienced by wiring systems are accumulated damage from exposure to chemical, thermal, electrical and mechanical stresses over time. The operational environment, installation and maintenance practices most often induce these aging mechanisms. Wiring failures often appear as broken conductors, failed connector interfaces and damaged insulation, which can disrupt electrical signals, cause short circuits or lead to arcing.

Today, aircraft are routinely flown well beyond their design life. The mechanical and thermal stresses and environmental degradation effects experienced by an aircraft during that time has an aging effect on the aircraft’s wiring systems. The Navy currently expends approximately 1.8 million man-hours annually troubleshooting and repairing aircraft wiring systems. Approximately 1,077 mission aborts and 147,674 non-mission-capable (NMC) hours per year are due to wiring incidents. In-flight electrical fires related to wiring failures are occurring at a rate of approximately two per month. A recent study on Air Force aircraft mishaps or accidents revealed 43% were related to the wiring interconnection system.

To manage costs and define work content, DoD maintenance depots normally tailor repair processes for items upon induction for repair. This process, known as evaluation and examination (E&E) or evaluation and inspection (E&I), is performed by specialists with extensive knowledge of repair processes and the end item being examined. As the depots become more focused on repair cycle time and supply chain integration, E&I becomes more critical to their success. Errors caused by citing the wrong repair process, technical documentation or part data can slow the entire process down and increase the cost of repair.

Enhancing the E&I process can provide more accurate access to technical and repair data and make the E&I itself more accurate. Creating hyper-linked, standardized descriptions of repair processes can speed E&I by as much as 40%, based on a 1998 DARPA study. In addition, the portable digital checklist can provide a consistent and accurate database for process and product engineers to use in defining future maintenance tasks. Making this data available to the engineering teams can be an essential part of efforts to lower the product’s total operating cost once it is repaired.

This proposed project addresses an intelligent, integrated manufacturing cell that is intended to produce detail machined aircraft structural members directly from digital engineering data through near net-shape metalworking processes as an integrated, intelligent process. This system would employ accepted computer integrated manufacturing (CIM), computer integrated design (CID), finite element modeling (FEM), intelligent processing of materials (IPM) and nonlinear analytical techniques to convert digital engineering data to the appropriate intelligent manufacturing models. The models provide the design for, and allow the manufacture of, metalworking tooling and dies that will be used in the production of the near net-shape high strength aluminum alloy replacement structures. These models are also shared in the detail machining of the near net-shaped products. Furthermore, to improve efficiency and maintain the properties and quality of the original wrought products, the intelligent near net-shape manufacturing cell shall employ additional intelligence by integrating a material or alloy selector as part of the modeler and nonlinear analysis to identify and idealize mechanical properties and to predict and minimize distortion. The objective of this effort would be to develop an integrated, near net-shape manufacturing cell to provide improved mission effectiveness and manufacturing supportability.

Enhanced Plasma Nitriding for Reduced Gas Turbine Engine Maintenance and Repair Costs (submitted by EMT, Inc.)

This project proposes using enhanced plasma nitriding (EPN) to achieve reduced maintenance and repair costs for gas turbine engines. EPN is an improved version of commercially mature conventional plasma nitriding. EPN has been successfully used to treat materials including titanium, stainless steels and aluminum. EPN utilizes lower pressures and temperatures than those used during conventional plasma nitriding, and produces durable, erosion resistant surfaces on these metals without decreasing their corrosion resistance (stainless steels) or fatigue life (titanium). EPN is also an environmentally friendly process that utilizes only nitrogen gas and electricity.

On cold-section parts, EPN is expected to yield the performance benefits of titanium nitride coatings yet also allow spot repair without stripping. On nickel-based hot-section parts, EPN has potential for producing durable and spot-repairable surfaces that could:

Depot-based Laser Ultrasonic (UT) Inspection for Rapid Non-Destructive Inspection of Composite Components (submitted by OO-ALC)

Current non-destructive inspection (NDI) techniques for aircraft composite components have known limitations including being manpower intensive, detail limited and image limited — all of which contribute to high cost-of-ownership and production impacts in the depot. Laser UT is a laser based ultrasonic testing process for rapid, detailed nondestructive evaluation of composite components. As a minimum, this would involve developing and testing the capability for 3-D, wide-angle image capturing, real-time image display, and capture of sample components data to identify inclusions, anomalies, discrepancies in advanced composite components and applications, including low observable applications. This would require the ability to continuously measure large-sized samples including complete aircraft parts such as spars, fittings, rudders, wing sections, etc. This project will involve the building, testing, and evaluation of an advanced prototype unit at OO-ALC depot Composite Technical Repair Center. Investigation of a movable system is also an interest (i.e., everything above the concrete could be moved to another facility).

Airborne generator repair frequently requires the rotor and stator assemblies to be rewound. This process is labor intensive and generally lacks the degree of precision to produce the highest quality product. More complex geometries, those that cannot be wound on 2-axis winding machines, are particularly difficult to produce manually. Installation of the coils into the end-item rotors and stators is also a labor-intensive process, which could be enhanced through the use of automation and robotics.

Currently, automated test equipment (ATE) is externally plugged into separate electrical outputs. This can cause a problem with the common ground requirement for testing avionics hardware. Although electrical power supplied to the ATE is commonly grounded, “floating” can randomly occur. Since avionics hardware is tested at the milli-volt and even micro-volt level, even a slight amount of noise can alter testing results and cause problems. The routing for the ATE and the power distribution module are needed to help eliminate noise. The proposed project will investigate and develop alternative techniques, processes, tooling, and strategies.

Retrograde Part Identification Using Second Generation Permanent Marking Techniques (NAVAIR)

NAVAIR is moving toward serial number tracking (SNT) to achieve total asset visibility, improvements in material reliability determinations, and removal/lessening of paperwork required from the war fighter. To achieve SNT’s goals, a quantum leap in data capturing/gathering techniques, data integrity, and data transferring will be necessary. At the heart of this effort is the need for automated information technology (AIT) to identify — uniformly, inexpensively, and permanently — a wide range of components/material that are routinely exposed to harsh environments (i.e., operating environment of an engine, exposure to industrial cleaning solvents, etc.). This project proposes to develop a cost effective/low cost, permanent application tool capable of applying AIT (i.e. 2D bar code, etc.) in a post-procurement environment to engine components (blades, hubs, vanes, etc.) that will not negatively impact the properties of the material being identified.

OO-ALC hosted our first Industry "Field Trip" on 14 March. Organized by Jim Freed, the industry participants learned of the needs and capabilities of OO-ALC, and had a chance to tour several of the facilities and discuss needs with the Ogden staff. We expect one or more projects to result from this interaction. We thank everyone at Ogden for their assistance. We are soliciting suggestions for the next depot visit; contact Chuck Ryan, 734-995-4905.

The NCMS 2001 Conference, being held May 6-8 at the Hilton Head Marriott Resort in Hilton Head, South Carolina, offers a “think tank” forum at which knowledgeable speakers and conference participants can interact to discuss the game changers that will come into play in building our preferred future. The purpose of this conference is to challenge our images of the future in an energized, exciting, and stimulating environment. Setting the stage for this environment will be keynote speaker Glen Hiemstra, whose work as a futurist is widely known and respected through his broad experience as an international speaker and consultant on future planning for enterprises. Mr. Hiemstra offers insight into surprising developments shaping the 21st Century, and then goes beyond that to the deeper challenge of understanding our new world and creating our preferred future.

If you have interest in any of the projects listed below, contact Chuck Ryan at 734-995-4905.

1	Equipment Parts Information Management System
2	Oxy Fuel Cutting Alternatives
3	Radio Frequency Locators
4	Reliability Based Maintenance
5	On-Site Paint Destruction
6	Robotic Painting Optimization
7	Propulsor Manufacturing Cell
8	Lead Free Solder

We appreciate your feedback. Please contact Chuck Ryan with suggestions or input on other topics that would be of interest to you in this newsletter. The CTMA Program is sponsored by the Department of Defense; the content of the information in this newsletter does not necessarily reflect the position or policy of the government; no official endorsement should be inferred.