AERONEXUM
Request a Demo

Reference

Aviation MRO Software

An MRO takes in a unit that cannot be used and gives back one that can, with a document that says so. The technical work is well understood and well controlled. The difficulty that costs money sits elsewhere — in discovered scope, in five coordination surfaces the shop does not control, and in the fact that most turn time is waiting rather than working.

What MRO software is actually being asked to do

An MRO exists to take in a unit that cannot be used and give back a unit that can — accompanied by a document that says so, signed by somebody authorised to say it. Everything else in the operation is in service of that sentence.

That framing matters, because it explains why MRO software is not simply a work order system with aviation labels on it. A work order system schedules and costs labor against a job. An MRO has to do that, and simultaneously hold together four other things: the physical unit and its changing condition, the material being consumed or fitted, the quality decisions being made about it, and the evidence that will eventually leave with it.

This page is about the operational coordination that job requires. It is not about the commercial system of record — that is covered on aviation ERP — and it is not a description of any particular product's screens.

The governing constraint

In almost every MRO, the metric that decides whether customers stay is turn time. And in almost every MRO, most of turn time is not work. It is waiting. Understanding where the waiting happens is the whole of the operational problem.

The path a unit takes

The sequence below is deliberately generic — a component shop, an engine facility and a line station differ enormously in the detail — but the shape is consistent across the industry.

Induction and incoming inspection

The unit arrives, usually with paperwork and usually not with all of it. Incoming inspection establishes what actually turned up: is it the part number claimed, is the serial number the one on the paperwork, is there shipping damage, is the removal reason consistent with what is visible, and is the documentation sufficient to work on it. A unit can be rejected here on paperwork alone, and a unit accepted here with a discrepancy that nobody recorded becomes an argument three weeks later.

Evaluation and quotation

The shop determines what is actually wrong and what it will cost. For anything beyond a routine inspection this usually requires disassembly, which means real cost is incurred before the customer has approved anything. Most MROs manage this with an evaluation fee and a not-to-exceed figure — and this is the point at which the first significant wait appears, because the unit now sits until somebody at the customer approves the quote.

Work, and the findings that change it

Work begins against an agreed scope. Then the scope changes, because that is the nature of the business: a part that looked serviceable is not, corrosion is worse than visible, a sub-assembly needs replacement that was not in the quote. Every one of those findings is a small commercial event requiring customer notification and frequently re-approval — and each one restarts the waiting.

Material

The unit needs parts. Those parts may be in stock, on order, on backorder with a long lead time, or available only as an exchange. If material is the constraint, the shop faces choices with real cost implications — wait, expedite at a premium, source used serviceable material with the trace burden that carries, or in some organizations rob a part from another unit and inherit that unit's problem instead.

Quality

In-process inspection at defined points, then final inspection, then the return-to-service decision by somebody holding the authority to make it. Quality is not a stage at the end; it is a series of gates through the job, each of which can send work backwards. How those gates get defined, applied and enforced is covered on aviation quality management software.

Release and documentation

The unit is only finished when its evidence is. The airworthiness approval tag, the teardown or work-performed report, any material certifications for parts fitted, and whatever else the contract specifies. A physically complete unit with an incomplete package has not been completed — it has been moved to a different queue.

Where turn time is actually spent in an MRO A horizontal sequence of MRO work steps — induction, evaluation, quotation, repair, quality inspection, release and shipping — with wait states shown between them. The waits are labeled with who is being waited on: the customer for approval, a vendor for material, a subcontractor for outside processing, and internal quality. A band beneath notes that the work steps are usually short while the waits between them are long. THE WORK STEPS — USUALLY THE SHORT PART Induction & inspection Evaluate & quote Repair Fit material Final inspection Release & ship THE WAITS BETWEEN THEM — USUALLY THE LONG PART Waiting on customer to approve the quote Waiting on customer to approve findings Waiting on material or outside processing Waiting on quality or rework Waiting on paperwork to be complete Four of the five waits depend on someone outside the shop floor. None of them is visible in a labor-hours view of the job, which is why shops that measure only work content are frequently surprised by their own turn times.
Turn time is dominated by the gaps rather than the work. The gaps are mostly dependencies on people outside the shop — which is exactly the part a job-costing view of the work does not show.

Why MRO is operationally difficult

The technical work in an MRO is demanding but well understood — it is performed by skilled people against defined data under an approved quality system. The difficulty that actually costs money sits elsewhere.

Scope is discovered, not specified

Most industries begin work knowing what the work is. An MRO frequently cannot know until it has begun disassembly, and the answer changes as the job proceeds. That makes every job a small commercial negotiation running concurrently with the technical work, and it means quoting, approval and communication are not administrative overhead — they are part of the production process.

Most of the elapsed time belongs to someone else

As the diagram shows, the dominant waits are on the customer, on vendors, on subcontractors and on internal quality. A shop can be extremely efficient at the work and still turn units slowly, because the constraint is rarely capacity. It is usually a decision or a delivery that has not arrived.

Several clocks run at once

A single job can simultaneously be waiting on an approval, on a part, on an outside process and on an inspection. Each has its own owner and its own expected date. Knowing which one is actually the critical path — as opposed to which one somebody asked about most recently — is genuinely hard, and it is where experienced coordinators earn their reputations.

The unit changes identity as it goes

A unit inducted as as-removed becomes work in progress, becomes a serviceable unit with a new tag, and may acquire a modified configuration along the way. Its condition, its value, its documentation and sometimes its part number are different at the end than at the beginning — while remaining the same physical asset, frequently still owned by the customer throughout.

Evidence accumulates as a by-product

The document package is assembled from things that happened during the job: inspection findings, parts fitted and their certifications, processes performed, approvals given. If those are captured as they occur, the package assembles itself. If they are captured afterwards, somebody spends the last day of the job reconstructing it — and that day is turn time too.

The five coordination surfaces

An MRO job touches five other parts of the business, and each contact point is a place where a job can stall without anybody deciding that it should.

  • The customerQuote approval, findings approval, status expectations, and the decision to repair, exchange or scrap. Usually the largest single component of elapsed time.
  • PurchasingMaterial for the job, outside processing, subcontract repair, and expedite decisions when a lead time will not meet the promise date.
  • InventoryWhat is on the shelf, what is allocated elsewhere, what is available as an exchange, and whether used serviceable material carries acceptable trace for this customer.
  • QualityIn-process gates, final inspection, disposition of discrepancies, and the return-to-service authority that no amount of schedule pressure can bypass.
  • DocumentationThe tag, the report, the certifications for material fitted, and the completeness check that determines whether the unit can actually ship.

Note what these have in common: the shop does not control any of them. A job's progress is a function of five relationships, and the coordination between them is the work that most MRO software leaves to people.

What organizations should think about

If turn time is the metric, these questions tend to locate where it is actually going:

  • For every job currently open, can you say what it is waiting on — in one place, without asking anyone? Most shops can produce a list of open jobs. Far fewer can produce a list of what is blocking each one.
  • How long does the average job spend awaiting customer approval? If this is not measured, it is almost certainly larger than assumed, and it is the cheapest thing to improve.
  • How many jobs are physically complete but not shipped? That queue is usually documentation, and it is pure turn time with no work content at all.
  • When a finding requires re-approval, how does the customer learn about it, and how do you know they saw it? If the answer is an email, the follow-up is somebody's memory.
  • How often is material the constraint, and how early do you know? Discovering a backorder in week three is a different business problem from discovering it at induction.
  • If the person who coordinates the shop floor were away for two weeks, what would degrade? The honest answer describes how much of your operating capability is held in one head.

How this connects to the Aviation Operating Platform

MRO makes the general argument unusually visible. The technical work is well controlled. The commercial record is well kept. And yet units sit — because the thing that determines turn time is the state of the coordination, and the coordination lives between systems and between organizations.

An Aviation Operating Platform is defined by holding exactly that: the state of the work rather than the record of it. What is committed, what is moving, what is blocked and what each blocked item is waiting on — including when the thing being waited on belongs to a customer or a vendor rather than to you. For an MRO that is not a reporting improvement. It is the difference between managing turn time and observing it afterwards.

The material side of the same problem is covered on aviation inventory software and aircraft parts inventory software. Where a repair is replaced by an exchange — a common and often better answer for the customer — the obligation that creates is covered on exchange core tracking.

Common questions

Is MRO software the same as a work order system?

No. A work order system schedules and costs labor against a job. An MRO also has to hold the physical unit and its changing condition, the material fitted or consumed, the quality decisions made about it, and the evidence that leaves with it — and has to coordinate all of that with a customer whose approvals are frequently the critical path.

Why is MRO turn time so hard to control?

Because most of it is waiting rather than working, and most of the waiting depends on people outside the shop: a customer approving a quote or a finding, a vendor delivering material, a subcontractor returning an outside process. None of that appears in a labor-hours view of the job, so shops that measure only work content are routinely surprised by their own elapsed times.

Why does scope change so often during a repair?

Because in most cases the full condition of a unit cannot be known until it has been disassembled and inspected. Findings that were not visible at evaluation are normal rather than exceptional, and each one is a commercial event requiring customer notification and often re-approval.

Why can a finished unit still not ship?

Because in aviation a unit is only complete when its documentation is complete. The airworthiness approval tag, the work-performed or teardown report, and certifications for any material fitted all have to be present and correct. A physically finished unit with an incomplete package has simply moved into a different queue.