- Every 50 starts
- Bearing temp above 90 °C
- Every 12 months
Preventive maintenance
Every cycle counts.
Epsilon3 maintains aircraft, engines, ships, vehicles, spacecraft hardware and the tools that service them on the hours, cycles and readings your procedures record. Not on a calendar, and not in a separate system.
Preventive maintenance film
- SN‑09Inspection
- SN‑07Due soon
- TS‑2Stand check
Count the use.
A Record Usage step in every run logs flight cycles, hours, starts and readings against the engine, tool or stand that did the work. Nobody keys in a meter reading later.
See it coming.
Routines trigger on cycles, hours, readings or dates, and turn Due Soon early enough to plan the work around flights, campaigns and deployments.
Out of limits. Out of service.
When a limit is reached or a routine comes due, check‑out, kitting and install can warn, ask to confirm or block the asset outright.
Maintenance is work.
Maintenance runs as a procedure: steps in order, readings captured, sign‑offs at the time. Finishing the run records it and resets the count.
Ready, and on the record.
One status view for every routine across the fleet, and a history where each maintenance action points to the run that did it.
- Verify stand and range clear3.1
- Chill‑down and start3.2
- Ramp to 100% throttle3.3
- Record usage · Engine SN‑073.4
- Sign off3.5
- UsageOverhaul at 200 startsResets those below
- UsageEvery 50 startsDue soon at 45
- ReadingBearing temp above 90 °CMeasurement
- ScheduleEvery 12 monthsFrom last done
- SN‑07Turbopump inspectionDue soon
- SN‑09Turbopump inspection22 starts left
- TS‑2Test stand checkDue in 3 days
- TW‑0312Torque wrench checkAt limit
- TW‑0318Torque wrenchAvailable
- TW‑0312Torque wrenchAt limit · blocked
- SN‑07EngineAvailable
- Borescope turbine blades1.1
- Record bearing clearance1.2
- Torque inlet flange to 45 N·m1.3
- Sign off for flight1.4
- SN‑07Turbopump inspectionDone today
- SN‑09Turbopump inspectionDue soon · 4 starts
- TS‑2Test stand checkDue in 3 days
- TW‑0312Torque wrench checkDeferred to Nov 24
- LF‑3Lift fixture proof testDue in 5 months
- Done · SN‑07 turbopump inspection
Recorded by run MAINT‑014 with three sign‑offs. Start count reset.
- Deferred · TW‑0312 torque wrench check
To Nov 24. Replacement anvil on order; tool blocked until then.
One solution. All platforms.
An airline counts flight cycles, a launch team counts starts, a destroyer counts running hours and an armored brigade counts rounds fired.
Airworthy, every cycle.
Track flight hours and cycles against every engine, life‑limited part and tool. Task cards run step by step, required inspections are signed in place, and return to service lands on the same record.
- HPT stage 1 diskLife‑limited partAt limit · blocked
- Torque wrench TW‑0312Tool cribAvailable
- Flight hours
- 41,236FH
- Flight cycles
- 18,412FC
- UsageEvery 1,500 flight cycles
- ReadingEGT margin below 15 °C
- ScheduleEvery 24 months
- Borescope HPT stage 1
- Record findings and images
- Inspector sign‑off
Ready to fly again.
Reusable vehicles live or die on turnaround. Count starts, burn seconds and flights against every engine and test stand, and refurbish on what the last flight actually did.
- Engine SN‑072 flights leftDue soon
- Hold‑down clamp set HC‑2Stand TS‑2Check due · blocked
- Starts
- 46
- Burn time
- 3,912s
- UsageEvery 10 flights
- UsageIgniter swap every 25 starts
- ReadingBearing temp above 90 °C
- Borescope turbine blades
- Leak check at 48 bar
- Replace igniter
Readiness is maintained.
Phase inspections on flight hours, landing gear on landings, and nothing flies on an overdue task. Mission capable rates start with maintenance done on time and on the record.
- Phase inspection12 FH leftDue soon
- Main gear brake assemblyWear pin readingAt limit · blocked
- Flight hours
- 2,412.6FH
- Landings
- 1,904
- UsageEvery 200 flight hours
- UsageLanding gear every 1,000 landings
- ScheduleEvery 400 days
- Inspect flight control linkages
- Record actuator readings
- QA sign‑off
Ready to deploy.
Running hours on every gas turbine, pump and generator. Planned maintenance on what the ship actually did at sea, with each check signed when it’s done, not when the availability ends.
- Fire pump 2Monthly testOverdue · blocked
- GTM 1A80 h leftDue soon
- Running hours
- 14,620h
- Starts
- 3,104
- UsageEvery 1,000 running hours
- ReadingLube oil metals above limit
- ScheduleEvery 6 months
- Borescope stages 1–3
- Record blade condition
- Supervisor sign‑off
Ready to roll.
Miles, engine hours and rounds fired, counted against every vehicle and weapon. Services come due on whichever arrives first, and a barrel at its round limit stays off the line.
- Barrel SN 4471Round limitAt limit · blocked
- Vehicle 3‑12Service in 410 miAvailable
- Odometer
- 18,240mi
- Engine hours
- 2,106h
- UsageEvery 6,000 miles
- UsageEvery 300 engine hours
- ScheduleEvery 12 months
- Change engine oil and filters
- Record brake wear
- Inspector sign‑off
Nothing lifts unproven.
Satellites aren’t serviced on orbit, but everything that touches them on the ground is. Lift fixtures, slings and test chambers are maintained on use, and an unproven fixture can’t be picked.
- Lift fixture LF‑312 lifts leftDue soon
- Sling SL‑9Proof testOverdue · blocked
- Load tests passed
- 6
- Days since proof
- 342
- UsageEvery 200 lifts
- ScheduleEvery 12 months
- UsageVisual check every 25 lifts
- Load to 125% rated capacity
- Record deflection
- Engineer sign‑off
Calendars guess. Separate systems forget.
Time‑based intervals treat a hard‑worked asset and an idle one the same. Maintenance tracked apart from the work turns every count into a re‑keyed number and every sign‑off into a lagging record.
Fixed intervals ignore the work. A fixed calendar pulls lightly used equipment in for work it didn’t need, and lets heavily used equipment run past its limit between checks. Studies cited by the US Department of Energy and DoD found most failures aren’t age‑related at all.
The gap is the record. When maintenance lives in its own system, usage is copied in after the fact, nothing stops a due tool from being picked, and the sign‑off trails the work. In Epsilon3 the procedure that runs the work records the usage, the same platform enforces the limit, and the maintenance is itself a signed run.
Same 90‑day interval, two machines
Illustration · inspection limit of 150 cycles
What it does
- Preventive maintenance triggered by recorded use (hours, cycles, starts, rounds, lifts), by readings and conditions your teams capture, and by schedule
- Limits and due routines enforced where assets are picked, kitted and installed
- Maintenance executed as procedures, signed at the time, on the same record as build, test and operations
Works alongside the condition‑monitoring tools you already run: Epsilon3 runs the work, enforces the limits and proves it was done.
What changes on the floor and in the field.
Last longer
Life limits, shop‑visit intervals, service life
Assets come due on the cycles, hours and readings they actually see, and warning levels flag wear before it becomes damage.
Run safer
Airworthiness, safety, mission assurance
Out‑of‑limit or due equipment can be blocked at check‑out, kitting and install. Maintenance follows the procedure and is signed when the work is done.
Cost less
Maintenance cost, O&S cost, spares
No teardown because the calendar said so, and no duplicate work: an overhaul resets the checks beneath it. One routine covers a whole fleet.
Stay ready
Dispatch reliability, uptime, MC rate
Due Soon windows give planners time to fit maintenance around flights, campaigns and deployments, and one status view shows what’s coming.
Plan.
Define the work, align schedules and dependencies, and keep teams coordinated as the program evolves.
For maintenance: maintenance windows sit beside flights, campaigns and depot periods. Routines are planned work, not a separate calendar.
Build.
Parts, BOMs, inventory and work orders, with the as‑built record written as the work runs.
For maintenance: every serialized unit leaves the floor with the history its routines attach to.
Test.
Test plans and requirements verified against live telemetry, with pass/fail limits and a complete as‑run record.
For maintenance: acceptance and qualification runs log each unit’s first hours, cycles and readings.
Operate.
Flight, launch, mission and range operations run live with go/no‑go gates and shift logs.
For maintenance: every run records usage as a step in the procedure, so nobody re‑keys a meter reading.
Sustain.
Routines come due on that usage, maintenance runs as signed procedures, and the unit in service carries the history it left the floor with.
Back to Plan: what maintainers find feeds the next procedure revision and the next build.
One system for the whole life of the program.
How it works.
- 1
Set up usage types
One list of usage types for the whole team. Each is a running total like cycles or hours, a current measurement like pressure, or a category like oil color, with its own units, decimals and reset rules.
Creating a usage type - 2
Apply usage and limits
Parts, tools and locations pick their usage types from that list, and every item or instance inherits them. Add a limit and choose what happens when it’s reached: allow use, warn and confirm, or block use.
Adding a usage type with a limit to a part - 3
Record usage anywhere
The Usage card on every item, tool instance and location shows each type’s current value. Record a reading, set a new total or reset it, and see the full history of readings.
Recording usage, then the history view - 4
Capture usage as the work runs
The Record Usage block logs usage for items, tool instances or locations inside any procedure, with several rows per block. Existing part and tool usage blocks keep working and convert in one click.
Converting an old block, then recording in a run - 5
Build maintenance routines
A routine has one or more triggers, each with its own procedure: a schedule, a usage amount or reading, or a number of check‑outs. Link it to a part to cover every item, or to a tool to cover every instance. Higher‑ranked triggers reset the ones below.
Creating a routine with a usage trigger - 6
Record maintenance
Status lists everything a routine covers with its due state. Record it as done, defer it to a new date with a reason, or cancel one occurrence with a reason. Finishing the maintenance procedure’s run records it automatically.
Recording maintenance from Status - 7
Find what’s due
Inventory and tool instance lists filter on Maintenance Overdue, Due and Due Soon next to expiry and usage‑limit alerts. Turn on the Maintenance column to see it at a glance.
Grouping Status, then the Alerts filter
Most of the cost comes after delivery.
Fleets are older, flown harder and kept longer, in airline service and in defense alike. Maintenance is where cost, safety and availability are decided.
- Civil aviation$136B
Global commercial MRO demand in 2025, on track for almost $193 billion by 2036.
Oliver Wyman, 2026–2036 forecast - Civil aviation~13 yrs
Average age of the global airline fleet in 2025, up about a year and a half in a year, with each aircraft flying more hours.
Oliver Wyman, 2026–2036 forecast - Workforce41%
Share of US certified aviation mechanics over 60. About 45,000 are expected to retire in the next decade.
Oliver Wyman, 2026–2036 forecast - Defense~70%
Share of a weapon system’s life‑cycle cost spent operating and sustaining it.
GAO‑26‑108140, April 2026 - Defense67%→44%
F‑35 mission capable rate, fiscal 2021 to fiscal 2025.
Defense News on GAO, June 2026 - Industry12–18%
Estimated savings of preventive maintenance over reactive maintenance.
DOE FEMP, via PNNL
Figures describe the industries, not Epsilon3 customer results.
Already on Epsilon3? Your schedules are already here.
Nothing to rebuild
Maintenance schedules, maintenance history, usage types, limits and usage history moved over automatically. Each schedule became a routine with one trigger, linked to the same part, item, tool or instance, with the same procedure.
What looks different
Anything Overdue reads Due. Usage‑based routines count from the latest reset, so some due dates may shift. Saved views that used the old Maintenance filter use the Alerts filter instead.
Convert at your own pace
Record Part Usage and Record Tool Usage blocks keep working in procedures and runs in progress. Each shows a Deprecated tag with a one‑click convert to Record Usage.