Article related to research:

Pentagon awards $4.7bn F-35 LRIP-8 contract to Lockheed

http://www.airforce-technology.com/news/newspentagon-awards-47bn-f-35-lrip-8-contract-to-lockheed-4448274

I found this article interesting because it illustrates the number of aircraft and cost associated in the next Low Rate Initial Production (LRIP) contract. Also included in the LRIP award is manufacturing as well as all the sustainment resources to include Spares and Support Equipment. Currently their are 10 LRIPs in the F-35 procurement strategy. LRIP-8 will begin in 2016 and bring the total number of delivered aircraft to just over 200. F-35 OT&E is scheduled for 3rd quarter 2017 through 3rd quarter 2018. OT&E must be complete before the program can enter Full Rate Production. That's a lot of time to wait for stability in the system design. Another risk in concurrent acquisition.

Factors that Influence Maintainability 

The Defense Acquisition University defines Maintainability as a characteristic of design that can be defined on the basis of a combustion of time, frequency, and cost (Dallosta & Simcik). The time required to repair or return a system to a serviceable condition is a significant contributor to aircraft availability. Any efficiencies built into the system design would reduce the amount of time the aircraft is down or unavailable to perform its intended mission. How often or the frequency at which a system or component requires maintenance attention is also a significant contributor to aircraft availability. Any activity above and beyond routine servicing directly impacts maintenance and drives additional sustainment support such as manpower and support equipment.  Finally, the cost to perform maintenance can be influenced by factors such as number of personnel and skill level require to perform the task, follow on maintenance associated with the parent task, and any peripheral support such as special equipment, facilities, and operational check out requirements. All of these factors, independent or in combination, will have a direct impact on the life cycle management strategy.

Although far from perfect, the F-35 program tried to build in maintainability as part of the overall supportability solution. Bit-in-Test (BIT) is one of the primary design influences intended to minimize the time associated with troubleshooting deficiencies. The contract requirement for system diagnostic capability established a 90% BIT function across the entire platform. Relying on self test to isolate faults reduces the time to repair. Leveraging technology one step further, the F-35 also introduced Prognostics Health Management (PHM) to enhance its aircraft availability.  Admittedly PHM is still in its infancy stage however once matured, through data collection, modeling validation, software refinement, and a host of algorithms this system will predict pending failure and enable preventative maintenance to occur in step with routine servicing or unscheduled maintenance. This capability depends largely on the 90% BIT capability which stems from a backbone of continuous system, sub-system and component performance monitoring.  

Other aircraft design factors considered frequency and used reliability predictions to determine component location in the overall design. Placing infrequently replaced assets in less accessible location and life limited or less reliable items in open areas such as wheel wells, weapon bays, and quick access panels illustrates the programs acknowledgment to design-in maintainability to improve supportability.  Poor design is a major factor leading to maintenance

problems. Consideration such as elimination of components that can be installed incorrectly should be addressed during design to minimize maintenance errors (Hobbs, 2008). Not without challenge, fielded F-35 aircraft face significantly higher maintenance events as the fleet of Low Rate Initial Production (LRIP) aircraft have life limited parts, reliability issues, and insufficient spare. This is not completely unexpected as the F-35 procurement is being managed as a concurrent acquisition program. Operational Units are already receiving LRIP aircraft and the F-35 program is still four years away from completing Operational Test and Evaluation. Lacking design stability, installed as well as spare parts are intentionally limited to prevent rework of surplus or disposition of obsolescent parts. This is however the Department of Defense preferred acquisition strategy even though it assumes higher risk in cost overruns, schedule impacts, and performance delays (DODI 5000.02).  

Finally, maintenance costs is a significant maintainability factor to consider in the sustainment solution.  Reduction in the manpower to support the aircraft will reduce the total ownership cost. Minimizing the number of specialized skill sets also streamlines the sustainment costs by leveraging a smaller pool of equally trained technicians across the entire platform. High saturation of BIT capabilities and predictive tools like PHM enable manpower reduction and sustainment costs. 

Maintainability of the system is dependent on finding a balance between time, frequency, and cost. For example, if you insist on the highest reliability to reduce the frequency of repair the trade off will be excess research & development, acquisition, operations & sustainment costs (Dallosta & Simcik). Designing-in maintainability and leveraging technology to streamline maintenance efficiency will reduce the total ownership costs. When procuring a new system using the DoD preferred concurrent acquisition method, it is important to establishing the sustainment strategy and widely distribute the milestone plan in order to keep the program on a consistent path to maturity.  

References:

Hobbs, A. (2008, December).  ATSB Transportation Safety Report, An Overview of Human Factors in Aviation Maintenance.      

         Retrieved from: http://www.skybrary.aero/bookshelf/books/550.pdf

Dallosta, P & Simcik, T. Designing for Supportability. Retrieved from: 

         http://www.dau.mil/pubscats/ATL%20Docs/Mar_Apr_2012/Dallosta_Simcik.pdf

US DoD. (2013, November 26) Operation of the Defense Acquisition System. Retrieved from:  

        http://www.acq.osd.mil/docs/DSD%205000.02_Memo+Doc.pdf

Spares and the Life Cycle Management Strategy

       This week I decided to take a closer look at how the spares allocation for a weapon system is determined.  Procurement costs for a new aircraft encompasses much more than the individual article or aircraft. In fact, sustainment accounts for approximately 60 to 80 percent of the total life cycle cost. Life-cycle cost (LCC) is the total cost for the weapons or support for defense acquisition system research and development (R&D), investment, operation and support (O&S), and disposal. (MIL STD 881C, para 2.3.4) The spares allocation to support a system can account for between 50 and 80 percent of the total cost of procurement (Myerson, 2012).  This is why finding the correct balance between cost, schedule, and performance is so challenging. The manufacture is interested in minimizing or deflecting cost in order to increase profit while the customer is concerned with ensuring performance for the negotiated cost. Of course schedule delays can have negative impacts resulting in direct and indirect cost for both parties. The specific acquisition strategy will have direct impact on replacement parts procurement plan and must be decided during the technology development phase.

Acquisition strategies for procurement of spares can be grouped into two approaches, demand-based modeling and readiness-based sparing. Spares to support legacy systems are driven from demand data. Essentially, inventory levels are established based on the frequency each item is placed on order. High demand items will have a larger number of replenishment articles available than infrequently consumed items. Demand data may provide accurate sparing requirements over time but, may prove to be sporadic and unpredictable. For example, consumption of a modulating engine bleed air valve could dramatically increase due to a change in corrosion preventative or metal plating of a sub-component within the valve body. Demand data would identify the unusual rate of consumption but not before the fleet was struggling with limited spare availability. An item manager could choose to flooding the supply system with excess inventory to ensure the weapon system can meet the customers performance (aircraft availability) requirements. However, as stated earlier, spares allocation accounts for approximately 50 to 80 percent of the total weapon system procurement cost (Myerson, 2012). Therefore, reducing the number of spares in the supply system will have significant impact on reducing total life cycle cost. 

A different approach could be a readiness-based sparing practice to optimize aircraft availability while decreasing the logistics footprint for sustainment spares (DoD 4140.1-R). This strategy looks to modeling data to predict the spares allocation requirements for system and sub-system assets. Elimination of surplus spares inventory in exchange for lean supply chain drive the life cycle cost down. Unlike the feast or famine cyclic environment of the demand-based supply strategy, readiness-based procures exactly enough to support the total life cycle based on reliability and maintainability predictions. Initial spares availability may prove to be challenging as the modeling data is validated. However, once stable, the supply chain management strategy should be able to achieve the required performance (aircraft availability) as defined by the customer. The implementation plan may be designed as a phased approach to help manage customer expectations. For example, initial spares procurement levels may be somewhat limited to assess proper range and depth of available inventory. Establishing  performance milestones to track program readiness may prevent surplus spares inventory. Additionally, assessing performance against validation of the modeling data will ensure manufactures design in reliability from the ground up.  

The most sophisticated weapon system in the world would be rendered totally useless if it breaks and no spares are available to return it to service. Spares to sustain the total life cycle of the system is balancing act between cost and performance. The spares allocation can be determined by demand-based data or readiness-based sparing. Each approach has its challenges but readiness-based sparing strives to procure sufficient assets to ensure the right parts are at the right place at the right time which drives total ownership costs down. 

References:

MIL-STD-881C. Work Breakdown Structures or Defense Material Items. Retrieved from: 

(https://acc.dau.mil/adl/en-US/482538/file/61223/MIL-STD%20881C%203%20Oct%2011.pdf)

Myerson, P. (2012). Lean Supply Chain Logistics Management. United States: McGraw-Hill Companies, Inc.

DAU, ACQuipedia. Readiness-Based Sparing (RBS). Retrieved from: https://dap.dau.mil/acquipedia/Pages/ArticleDetails.aspx?   

         aid=5171139a-98c0-4726-b214-00abd4dcf474

Understanding the Supply Chain and Lifecycle Management

     During the past two weeks I have visited a massive aircraft storage site as well as a depot that performs repair and modifications to multiple military weapon systems. The first stop on my trip took me to Davis-Monthan Air Force Base outside Tucson, AZ. We were to assess the unit compliance within  the 309th Aerospace Maintenance and Regeneration Group (AMARG). Communally referred to as the "bone yard" Davis-Monthan houses approximately 4,400 military aircraft that have been pulled out of active service (AMARC Experience). Aircraft that have outlived their service life are stripped of any useful parts and recycled. Other aircraft are preserved awaiting regeneration or reentry into service as a fully operational aircraft. Management of the national assets is a very demanding task for the men and women of the 309th AMARG. Their responsibilities are outlined in Air Force Instructions, Standard Operating Procedures, and Policy Letters. Other sites such as Pinal Airpark in Marana, AZ serve the equivalent role as a bone yard for commercial aircraft.  Both AMARG and Pinal Airpark support similar activities however, Pinal responsibilities are defined solely from a host of FAA Regulations.

  One of the principle roles each bone yard serves is harvesting parts to support operational aircraft. Simply stated, Supply Chain Management (SCM) is the activity that tries to place the right part at the right place at the right time to support the organization's mission. If the existing spares allocation are exhausted, Item Managers can look to sites such as AMARG or Pinal to source additional inventory to increase the availability. This action may be as a necessity due to a number of different reasons. 

  One example of constraints on having an adequate spares allocation could be unforeseen challenges or changes in the lifecycle management plan. For example, if a manufacturer designs a component to perform without repair for half the lifecycle of the parent system, item managers will develop the sustainment solution to support that expectation. However, if over time the assets actual performance is half of what the manufacture predicted, the existing number of spares is approximately half of what is require while the planed sustainment cost has now doubled. Pulling resources from the bone yards may help relieve some of this lifecycle management pressure. Once inspected and tested for serviceability, by an approved authority, these parts could increase the number of available spares (FAR 43.2(2)).

Another example could be Diminishing Sources and Material Shortages (DMSMS). Essentially, this is the inability to sustain an item due to loss of the manufacturer or required material (DAG, page 237). An example would be a replacement 8-track tape player head. Once leading edge, this technology was overcome by caste tape and compact disk. Although you may find something through a specialized vender, chances of finding exactly the player head you are looking for would be nearly imposable and whatever you may find would definitely cost more. Pulling assets from the bone yard could provide you additional resources to sustain the assets no longer supported by manufacturers. Depending on depth of resources, this solution may prove to be temporary but it may provide sufficient time to implement something more permanent. CFR Part 43, paragraph 43.2(b) defines overhaul and testing requirements that must be met prior to returning an asset to serviceable inventory for use on aircraft (CFR 43.2).   

The second half of my recent trip gave me an in-depth look at the capabilities within the Air Logistics Complex (ALC) at Hill AFB, UT. The ALC provides support for both aircraft and commodities or component level assets. Not only is this site responsible for aircraft slated for Program Depot Maintenance (PDM) on several weapon systems, it also performs major repair and modification (Hill AFB). Schedulers work closely with the DoD and Foreign Military Services to define the planned workload and schedule the weapon system or sub-system for repair, overhaul, modification, or regeneration. Planning for induction into the depot is no small task and the effort is only compounded by the level of repair required. Running parallel to their PDM activities is a modification capability for both on and off equipment assets. From corrosion control to aircraft structural modifications the team at Hill runs the full spectrum of maintenance capabilities. One key element to successfully completing a PDM or a modification is parts availability. This is where the activities at Davis-Monthan and Hill interface with incredible synergy. Keeping the PDM or Mod lines fed with serviceable parts is the difference between an on-time delivery or delays in returning the weapon system to the customer. 

If additional aircraft or spare parts are required, recovering them from storage may be the only option. Regeneration of stored aircraft or parts begins at the bone yard and finishes with the ALC. For example, one of the assets the ALC had just released from flight test was a former US Marine Corp C-130 Hercules aircraft. This C-130 was removed from storage at Davis-Monthan and has now returned to fully mission capable for reuse as a Foreign Military Sale. Part of this effort was not only ensuring the aircraft met air worthiness requirements but also included several modifications to upgrade or modernize the platform to meet the customer requirements. Interesting thing to note is the airworthiness process in this case was twofold. Initially the aircraft had to meet certain certification criteria to be flown from Davis-Mothan to Hill under a US certificate. Once modified, the airworthiness certification must meet the requirements as defined by the nation policy of the country that takes possession of the FMS aircraft. The exporting agency has the responsibility of forwarding all documentation to the importing country (FAR 21.335).

Aircraft aren't the only things to come out of the bone yards. Components also find their way to the ALC at Hill. At first glance some of the items I saw looked more like scrap metal heading to salvage. However, these assets are desperately need to support the activities within the depot as well as replenishment to support the Warfighter.  Remember what was discussed earlier about returning aircraft parts for use on aircraft can only be accomplished after it has been inspected and tested by an approved person? Again CFR Part 43, paragraph 43.2(b) defines overhaul and testing requirements that must be performed (CFR 43.2) and CFR 43.3 further defines who is authorized to perform these tasks (CFR 43.3). Each of the items that passes through the ALC are meticulously tracked to ensure all requirements are met and the end product makes it way to the proper location, on-site or returned to the global sustainment pool managed by the Defense Logistics Agency or DLA. 

So what does all this really mean? First and foremost, spares are a critical element for sustainment of all weapon systems. Second, entire industries are in place to support the repair, overhaul, and modification of aircraft and their components. Third, the authority to the repair, overhaul, and modify assets is defined in FAA Regulations. Finally, nowhere in this research did the responsibility to maintain the airworthiness standard fall to the aircraft manufacturer. The owning agency or permit holder is responsible for ensuring proper inspection surveillance, preventative maintenance, and alteration of the aircraft (CFR 121.373). 

References:

AMARC Experience. What is AMARG. Retrieved from: http://www.amarcexperience.com/ui/index.php?option=com_content&view=article&id=2&Itemid=213

DAG. Diminishing Manufacturing Sources and Material Shortages. Retrieved from: https://acc.dau.mil/docs/dag_pdf/dag_complete.pdf

FAA. 14 CFR Part 21 Certification Procedures for Products and Parts. Retrieved from: http://www.ecfr.gov/cgi-bin/text-idx?rgn=div5;node=14%3A1.0.1.3.9#sp14.1.21.l

FAA. 14 CFR Part 43 Maintenance, Preventative Maintenance, Rebuilding, and Alteration. Retrieved from: http://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&SID=294de5e7173c97d9599f0fb0af600b6b&tpl=/ecfrbrowse/Title14/14cfr43_main_02.tpl

FAA. 14 CFR Part 91 Subpart E—Maintenance, Preventive Maintenance, and Alterations. Retrieved from: http://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&SID=49ecddd9db69b61c093fe6c9704dafd2&rgn=div6&view=text&node=14:2.0.1.3.10.5&idno=14

FAA. 14 CFR Part 121 Subpart L—Maintenance, Preventive Maintenance, and Alterations. Retrieved from: http://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&SID=294de5e7173c97d9599f0fb0af600b6b&rgn=div6&view=text&node=14:3.0.1.1.7.12&idno=14

Hill Air Force Base. Ogden Air Logistics Complex. Retrieved from: http://www.hill.af.mil/library/factsheets/factsheet.asp?id=5594