Team ILCS

PERFORMANCE MEASUREMENT OF MAINTENANCE USING SRT, AMT, AND TAT

Another in our series of ideas and topics for discussion within the Life Cycle Support community… this time looking at time-based metrics for maintenance repair tasks, oriented towards military equipment maintenance. Effective maintenance of military equipment is central to force readiness, operational availability, and life‑cycle cost control. Defense organizations rely on structured time‑based metrics to understand how long maintenance should take, how long it actually takes, and how long equipment remains unavailable to the warfighter. Three complementary measures—Standard Repair Time (SRT), Active Maintenance Time (AMT), and Turn‑Around Time (TAT)—can provide a comprehensive view of maintenance performance across planning, ex*****on, and operational impact.

THE ROLE OF TIME‑BASED METRICS IN MILITARY MAINTENANCE
Military maintenance operates under unique constraints: dispersed operating environments, mission‑critical timelines, complex weapon systems, and strict configuration control. DoD policy emphasizes consistent, measurable maintenance processes across the life cycle. DoD Instruction 4151.18 establishes the requirement for structured maintenance performance management across all components and levels of repair, reinforcing the need for standardized metrics to evaluate readiness and sustainment effectiveness. Time‑based metrics support:
• Predictable planning and scheduling
• Accurate manpower and resource allocation
• Identification of systemic delays
• Sustainment design improvements
• Readiness reporting and decision‑making

STANDARD REPAIR TIME (SRT): THE PLANNING BASELINE
Standard Repair Time (SRT) represents the expected duration required to perform a specific maintenance task under normal conditions. In military contexts, SRTs may be derived from OEM technical manuals, engineering analyses, historical performance, and standardized task libraries (e.g., maintenance allocation charts). SRT is used to:
• Estimate labor requirements
• Develop maintenance schedules
• Support manpower modeling
• Benchmark technician performance
Because military systems often have complex fault isolation procedures, SRTs must account for diagnostic steps, tooling requirements, and multi‑skill labor. When SRTs are inaccurate or outdated, planning becomes unreliable, leading to cascading delays across units, intermediate shops, and depots.

ACTIVE MAINTENANCE TIME (AMT): MEASURING HANDS‑ON WORK
Active Maintenance Time (AMT) captures the actual hands‑on time a maintainer spends performing corrective or preventive maintenance. The RMQSI Knowledge Center defines Active Corrective Maintenance Time as the portion of maintenance during which corrective actions are performed, explicitly excluding logistics and administrative delays such as waiting for parts or shift changes. AMT is essential for:
• Technician efficiency measurement
• Identifying training or tooling gaps
• Understanding variance from SRT
• Supporting continuous improvement
In military environments, AMT is often tracked through Maintenance information systems (e.g., LMP, NALCOMIS, GCSS‑Army), Time charging codes, and automated data collection tools Comparing AMT to SRT can highlight whether deviations stem from ex*****on inefficiencies or from unrealistic planning standards.

TURN‑AROUND TIME (TAT): THE OPERATIONAL READINESS METRIC
Turn‑Around Time (TAT) measures the total elapsed time from when an item becomes unavailable due to failure until it is restored and returned to service. The US Warfighter (formerly Defense) Acquisition University defines Repair Turnaround Time (RTAT) as the elapsed time from component failure to capability restoration, emphasizing its direct impact on system availability and mission readiness. TAT can include time segments attributed to various elements affecting repair task completion, such as:
• Time to deliver equipment to the repair facility
• Queue time at the facility before maintenance begins
• AMT (hands‑on work)
• Supply delays (awaiting parts)
• Other administrative delays, such as waiting for a repair bay or specific tools/test equipment
• Quality assurance and testing after repair is completed
• Shipping, transportation or transfer of the equipment back to the customer
TAT is the most comprehensive metric because it reflects the customer/warfighter’s experience: how long equipment is actually deemed to be out of service by those who use/need it.

HOW SRT, AMT, AND TAT WORK TOGETHER
A three‑tier structure (shown below) illustrates how each metric contributes to measuring maintenance performance and readiness. Generally, we can say:
• SRT → establishes expectations
• AMT → measures ex*****on against expectations
• TAT → reveals full operational consequences

APPLICATION ACROSS MILITARY MAINTENANCE LEVELS
At the organizational/Unit Level (1st line):
• SRT supports daily scheduling and mission planning.
• AMT, when compared to SRT, can highlight technician skill gaps or equipment access issues, or even poor SRT job estimates.
• TAT reflects the customer operational downtime, which can affect their mission capability.
Analyzing non-AMT segments of it to determine dominant causes can highlight maintenance process inefficiencies and areas for improvement. At an intermediate Level repair facility (2nd line):
• SRT informs shop loading and shift planning.
• AMT may identify inefficiencies in troubleshooting or repair processes.
• TAT reveals supply chain, personnel, facility or test equipment constraints.
At an in-depth Depot Level repair facility (3rd line):
• SRT supports workload planning and industrial base capacity modeling.
• AMT can be used for labor standards, cost accounting, and productivity.
• TAT is critical for managing repair pipelines and meeting readiness goals.

EXAMPLE: APPLYING THE METRICS TO A MILITARY REPAIR SCENARIO
A radar component fails during operations and is removed for repair.
• SRT for the repair is 6 hours based on depot standards.
• AMT recorded by technicians is 5.2 hours.
• TAT is 19 days due to shipping, parts delays, and QA testing. A possible interpretation from the analysis and comparison of these times may suggest:
• Ex*****on was efficient (AMT < SRT).
• Readiness impact was driven by supply and logistics delays, not technician performance.
• Improvement efforts should target supply chain responsiveness and depot queue management.

WHY THESE METRICS MATTER FOR MILITARY READINESS
As shown, these metrics can:
• Support force availability by reducing downtime.
• Improve sustainment support solution design by identifying maintainability issues early.
• Enable data‑driven decisions for resourcing, training, and modernization.
• Support DoD policies requiring measurable, performance‑based maintenance management.

SOURCES:
DoD Instruction 4151.18:https://www.esd.whs.mil/Portals/54/Documents/DD/issuances/dodi/415118p.pdf
RMQSI Active Corrective Maintenance Time definition: https://www.rmqsi.org/glossary/active-corrective-maintenance-time/ Warfighting Acquisition University - Repair Turnaround Time (RTAT): Repair Turnaround Time (RTAT) | www.waru.edu

ILCS IDEA - IKEA Meets Military Parts Inventories

Traditionally, defense supply chains catalogue and hold individual spare parts as separate items. While this can ensure minimum items are used in repair, and optimize use of common items, it can mean 10,000+ items are identified, separately procured, packaged and distributed to support a single vehicle system and the 100s of repair tasks needed to sustain the fleet. Often 10+ spare part orders need to be raised to complete a single repair task.

WHAT IF WE STOCKED PARTS LIKE IKEA??
What if instead of individual piece parts, we catalogued and stocked repair task kits (RTKs)? ONE number, ONE order for ONE job? Advantages could be:
1. simplified ordering
2. no need to store partial orders until last item arrived (and risk losing something and needing to reorder)
3. Much reduced cataloguing effort and supply chain actions below central warehouses
4. easier Available-to-Promise (ATP) parts delivery estimations and easier/more accurate maintenance planning.

EXAMPLE - Swedish BV206 stocking
Our founder was the Canadian PM for a purchase of Swedish BV206 vehicles and support in the 1980s. At that time, Sweden had a predominantly conscript army, with most vehicle operators, technicians and supply staff all serving less than two years. An example RTK for replacing an alternator could include the alternator, mounting bracket, attaching hardware and even wrenches. The RTK could also include repair task instructions to reduce the need to refer to maintenance manuals. By applying this RTK concept, the Swedish Army could:
1. catalogue/stock only ~ 600 RTKs, vice the usual ~ 5,000 individual parts
2. have simpler planning and ex*****on of maintenance jobs
3. provide standard sets of RTKs pre-stocked at unit and supporting maintenance organizations, based on their assigned maintenance responsibilities.

EXAMPLE - Canadian Army Vehicle Modification Kits
Modifications and upgrades to in-service fleets were often done as a lower priority maintenance job. Based on provided modifications, 10-20 items were ordered separately and stored locally at the maintenance unit until all items were available and technicians/vehicles were available for the installation. Often, items were lost/misplaced and reordered. As a result, central equipment management teams often needed to procure or reprocure excess items well beyond the actual installed quantities needed. By switching to a RTK concept for modification kits, much of these issues disappeared and modification programs were completed faster and cheaper!

DOES THINKING LIKE IKEA WORK FOR YOU?
Would use of RTKs make sense for support of your equipment fleets? Do you already use this concept? We'd love to hear your thoughts!

Going through annual performance review cycles had me remembering a conversation with Martin P., one of Pennant Canada's consultant contractors (and an avid model aircraft enthusiast). Martin was talking about his time working at General Dynamics Mission Systems–Canada as an ILS manager. His program manager came around and said they were instituting a new performance bonus regime and asked "what would be a good metric for an ILS manager like you". Martin thought a moment and then said... "the phone doesn't ring!" A cheeky but valid response... if we put in place an optimized and resilient support solution, a true indicator can be the LACK of CRISIS CALLS.

How would you measure success in creating and managing an IL(C)S support solution? Does Martin's answer work for you??

Another in our series of ideas and topics for discussion within the Life Cycle Support community, this time looking at an idea (and, in fact in our experience, an often-used fix) to improve repair parts supply and reduce downtime.

This graphic depicts the traditional hub & spoke military supply chain model and adds the idea of lateral flows (often called lateral transshipments or inventory pooling) for spare parts between local units, for discussion.

Head over to our website to read the full article: https://www.teamilcs.com/lateral-thinking-in-defense-parts-invent

I recently had some discussion regarding the name I choose for my company and in particular, the acronym ILCS.
Check out this article on my website for full details: https://www.teamilcs.com/why-we-like-ilcs

A little bit about Pat:

Pat Read brings more than 55 years of combined military and industry experience in product support, equipment management, and integrated life cycle support (ILCS). Throughout his distinguished career, he has led Canadian Army and Multi-National Force allied maintenance workshops, directed Department of National Defence (DND) Equipment Program Management Directorates, and contributed to major equipment acquisition initiatives.
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A recognized authority in supportability and product life cycle standards, Pat has developed business process models for DND and contributed to the ISO 10303 AP239 Product Life Cycle Support standard. He remains actively engaged in international product support standards organizations, helping shape best practices that influence defence and industry worldwide.
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Pat retired from the Canadian Army in 2000 at the rank of Lieutenant-Colonel, following 30 years of service in maintenance and engineering leadership roles within the Corps of Royal Canadian Electrical and Mechanical Engineers (RCEME). His military career established the foundation for his deep expertise in operational readiness, sustainment strategy, and engineering leadership.
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In 2001, Pat joined Pennant Canada, where he founded the company’s consulting services division. Under his leadership, the team became widely recognized for developing integrated life cycle support policy and guidance for DND and for enabling effective ILCS implementation across major industry providers. He continues to serve as a Director of Pennant Canada while focusing his efforts on building and expanding Team ILCS and fostering a global ILCS community of practice.
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Pat is a registered Professional Engineer with Professional Engineers Ontario (PEO), holding a Bachelor of Science in Mechanical Engineering along with advanced military technical and operational staff training. He is an active member of the Project Management Institute (PMI), SAE International, and the Council of Logistics Engineering Professionals (CLEP). He also served as Past President of the EME Association, a core organization within the Canadian Conference of Defence Associations (CDA).
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Outside of his professional life, Pat is married to Maggie and is the proud father of four grown children. Their household includes three cats and two dogs. Pat continues to pursue his long-standing goal of consistently breaking 100 on the golf course, or at least beating his buddies occasionally.