SystemInflight Services & Supply Chain

Aircraft Spare Parts Demand Forecasting

Aircraft spare parts demand forecasting that puts the part on the shelf before the aircraft needs it

Parts on the shelf before the aircraft needs them, and idle stock turned back into cash.

See one case, screen by screen ↓
demo9brakesforecast for O'Hare's 787-9s in 30 days against 4 on the shelf, from 11 brake wear alerts on six aircraft
demo120daysplanning lead time for a brake the supplier quotes at 60 — its last four orders took 112 to 127
target40%fewer aircraft grounded for a part: 9 a month to 5
target60%less emergency spot buying, paid at about 4.8 times the planned price
In short

What is Aircraft Spare Parts Demand Forecasting?

Aircraft spare parts demand forecasting predicts how many of each part every station will need, and when, so the part is on the shelf before the aircraft needs it. Aircraft Spare Parts Demand Forecasting does it with eight agents that read component removals, health alerts, the flying, check and fleet plans and the supplier's real delivery record, forecast each part at each station for 30, 60 and 90 days, set min/max stock levels and propose a borrow, transfer, order or sale. The materials planner approves, edits or rejects every one.

How to choose AI for airlines: a buyer's guide to agentic AI solutions →

Updated

The problem

Why aircraft spare parts demand forecasting still misses the part you could see coming

Aircraft spare parts demand forecasting at most airlines still means min/max levels set once a year from 24 months of issues in the maintenance and engineering system, reorder points that fire a requisition when stock dips, and the lead time the supplier quoted. The materials planner learns a part is short when maintenance control calls. Brake wear alerts, a slow APU start, a supplier's slipping deliveries and the new aircraft on the fleet plan never reach the forecast.

So a no-go part — one the MEL gives no relief for — grounds an aircraft at one station while the same part sits idle at another. The AOG desk borrows, robs another aircraft or buys at spot, and a spot buy costs about 4.8 times the planned price. Meanwhile slow-moving stock from retiring fleets waits for the annual write-down, and an acquired airline's shelves sit under part numbers nobody has mapped.

typical1.4$Bspent by airlines on holding surplus spare parts in 2025, as they stockpile against unreliable deliveries
typical11$Band more in supply-chain costs to airlines in 2025, from extra fuel, extra maintenance, engine leasing and surplus spares
typical4.8×the planned price, for a part bought in an emergency when an aircraft is on the ground
Where one no-go shortfall's hours goestimated
By hand11 days
With the solution1.4 days
  • Reading health alerts and removals to judge what is coming3 → 0.3 d
  • Finding the supplier's real lead time and open orders2 → 0.2 d
  • Looking for a spare at other stations and in the pool2.5 → 0.2 d
  • Comparing borrow, transfer, exchange and order1.5 → 0.2 d
  • Checking the release certificate and the approval limit1 → 0.2 d
  • Raising the loan request and purchase order, and signing off1 → 0.3 d

Estimated split for one no-go shortfall at a hub station, from the first warning to an approved borrow and order, by hand and with the solution.

How it works

How a shortfall is closed

Eight agents forecast every part at every station and propose the move; the materials planner approves every order.

What comes in
Signals in7 systems · removals, health alerts, flying, POs, pool
Agents at work
Fleet Health Readeralerts to removals
Demand Forecaster30, 60, 90 days
Lead Time Watcherreal lead times
Then
Stock Level Setterlevels by criticality
Sourcing Plannerborrow, transfer, order
Proposal Checkerre-derives independently
Then
Surplus Finderidle stock to cash
Fleet Change Plannerdeliveries, acquired fleet
A person decides
Materials plannerapproves, edits or rejects
What comes out
Part on the shelf in time
Loan request and PO on record
Idle stock back to cash
One case, step by step

One shortfall in aircraft spare parts demand forecasting: O'Hare's 787-9 brakes

Thursday, October 15, 2026, 08:40 at O'Hare. Brake wear alerts are rising on the 787-9s that Corvane Airways bases at ORD. Here is how the agents and the materials planner close the gap, screen by screen, in the working solution.

  1. 0108:40

    The next decision, first

    Marisol Ortega · Materials planner, ORD

    The agents re-planned every station at 08:12. Marisol's Today screen opens on one card: brake assemblies at ORD run 3 short from Oct 24. Below it, 14 shortfalls ahead at 8 stations, 9 proposals waiting for her worth $1.24M, and $38.6M of idle stock with a proposal. A feed shows what each agent found since 06:00.

    “The agents propose to borrow 3 from the pool and order 2 at $96,000 each: $203,700. Decide by 16:00 to catch the pool's 48-hour delivery.”

  2. 02Review on the map

    Every station's shelf against its 30-day need

    Marisol Ortega · Materials planner, ORD

    The stock map shows brake assembly BRK-789-4120, a no-go part, at every Corvane station: ORD 4 on the shelf against 9 needed, SFO 5 / 4, DEN 3 / 2, LHR 2 / 1, NRT 2 / 2. The Meridian pool at DFW has 6 free, and a dashed arc marks the proposed borrow of 3 arriving Oct 17. Beside the map is the conversation with the agents about ORD.

    “Label: on the shelf / needed in 30 days · click a station to talk to the agents about it”

  3. 0308:12

    The aircraft are saying it, with the source

    Fleet Health Reader

    Eleven brake positions on six ORD-based 787-9s fell below 20% wear remaining in 9 days, against 4 in a normal 9 days. The first, Ship 2914 brake 3, is at 17% and reaches its 10% removal limit about Oct 24. Every number in the conversation opens its source: here, the aircraft health monitoring brake wear report, position by position.

    Confidence 0.93 · 11 alerts read

  4. 0408:13

    9 needed at the 98% level, likely 7 — history alone said 4

    Demand Forecaster

    The part forecast shows 90 days of weekly demand at ORD with its range and the first short day. What moved it, each driver cited: the wear alerts add 3, removals history says 4, flying is up 4% with the added ORD–GRU frequency from Nov 1, and Ships 2945–2948 join ORD from January, so its stock level rises from 6 to 8. Brakes have no MEL relief, so the plan-to level is 98%.

    Confidence 0.91 · range 6–10. The forecaster shows a range, never a single number.

  5. 0508:14

    The supplier quotes 60 days; its brakes take 120

    Lead Time Watcher

    Ardent Brake Systems quotes 60 days, but its last four brake orders took 112, 118, 121 and 127 days, so the agents plan on 120: an order placed today arrives about Feb 12, 2027. On Supplier lead times, the watcher also read Halvorsen Hydraulics' email moving PO-48610 from Nov 20 to Jan 8, and proposes 96 days for its pumps — waiting for Marisol to accept.

    “Rule: plan on the 80th percentile when actual exceeds the quote by 25%”

  6. 0608:15

    Every way to close the gap, compared

    Sourcing Planner and Proposal Checker

    Four on the shelf plus 2 back from repair by Oct 29 leaves ORD 3 short from Oct 24. The Sourcing Planner compares a pool borrow of 3 plus an order of 2 ($203,700, covered Oct 17), a transfer from DEN ($200,450, DEN short risk 19%), waiting for the repairs ($192,000, a 61% chance of a grounding) and an AOG spot buy (about $1.38M). The Proposal Checker re-derives the forecast from raw removals and alerts, confirms each pool brake ships with an FAA 8130-3 under clause 4.2, and that $203,700 is inside Marisol's $250,000 limit.

    Proposal P-2041 · confidence 0.91 · Proposal Checker: “Agrees · independent check”

  7. 0708:40

    “Use DEN's spare first”

    Marisol Ortega · Materials planner, ORD

    Marisol tells the agents what she would try. The Sourcing Planner re-plans: move 1 from DEN by road, here Oct 16 for $650, borrow 2 and order 2 — $200,450, $3,250 less. The Proposal Checker answers in the same thread: DEN would then hold 2 for its own 2 expected changes, with nothing spare until Nov 9, and its chance of a short day rises from 2% to 19%.

    Proposal Checker: “I would keep the pool borrow.” · Switch to this plan · Keep the original

  8. 08Approved

    She keeps the plan and approves with a reason

    Marisol Ortega · Materials planner, ORD

    Marisol keeps the original and approves P-2041 with the reason “Forecast agreed”. Only then does the Sourcing Planner send loan request LR-58213 to Meridian Component Pool, which acknowledges it, and put purchase order PO-48862 into purchasing for release. ORD turns from short to covered on the map, and each step is on the audit trail.

    “ORD covered from Oct 17 · logged”

  9. 09The rest of the morning

    Nine proposals, each with a clock

    Proposal Checker

    Decisions lists every borrow, transfer and order the agents propose, sorted by when it must be decided. The Proposal Checker re-derived all nine from raw data: P-2043, bleed air valves for the Halden A220s at BOS, is below 0.80 confidence, and P-2045, $284,000 of engine-driven pumps for SFO, is over the limit, so Angela Brooks-Hale co-signs. Three are under $5,000 and can be approved together.

    “Every borrow, transfer and order the agents propose. Nothing is sent until a person approves it.”

  10. 10Maintenance control

    A false alert never buys a part

    Kenji Abernathy · Maintenance control manager

    Fleet health signals lists the 37 alerts read since 06:00 and the forecast each changed. Eight changed a forecast. One — a brake temperature sensor reading 0 °C on one wheel of Ship 6077 at EWR — looks like a sensor fault, so the Fleet Health Reader did not count it and asked maintenance control to confirm. Maintenance control can correct any signal, and the agents re-forecast.

    “Not counted: likely a sensor fault, not wear”

Who it’s for

Built for everyone who answers for the shelf.

The same spares network, seen by four of the people who carry it — what their week looked like, and what it looks like now.

MO
Marisol OrtegaMaterials planner, ORD hub · approves to $250,000
Materials planner
Before
Owns the shelves at ORD and the line stations it supplies. “I find out a part is short when maintenance control calls me.”
Now
Starts with what will run short, sees the proposal and its reasons beside the station on the map, asks the agents about any shelf and approves with a reason.
TL
Trevor LindqvistInventory manager · surplus, provisioning and stock rules
Inventory manager
Before
Sets stock levels in the annual review and owns surplus and write-downs. “Half my surplus is the same part someone else is short of.”
Now
Decides each sale, move or consignment the Surplus Finder proposes, keeps insurance spares with a reason, and decides the Halden one-way interchangeability items.
AB
Angela Brooks-HaleSupply chain director · $612M of spares · co-signs above $250,000
Supply chain director
Before
Answers to the VP Technical Operations for the spares budget. “Show me the reason before you show me the invoice.”
Now
Co-signs only the orders over the limit, approves service levels and approval rules, and reports results measured from the maintenance control log and purchasing.
KA
Kenji AbernathyMaintenance control manager · 24/7 maintenance control center
Maintenance control manager
Before
Needs the part before the aircraft is grounded. “A brake I can see coming should never ground an airplane.”
Now
Sees every health alert with the forecast it changed, corrects a known sensor fault, and is alerted when a no-go shortfall is under 72 hours away and undecided.
Built on the engine

8 agents. Each with one job, and hard limits.

Eight agents forecast every part at every station and propose the move; the materials planner approves every order.

Fleet Health Reader

Turns aircraft health alerts, maintenance messages and wear trends into expected removals per aircraft and date — brake wear, slow APU starts, bleed faults, pump pressure.

  • Never treats a single alert as a removal without a trend or a confirmed fault
  • Flags likely sensor faults and asks maintenance control
Demand Forecaster

Forecasts demand per part, station and horizon — 30, 60 and 90 days — from 36 months of removals, utilization from the flying plan, the check plan, the fleet plan and health-driven removals.

  • Shows a range, never a single number
  • Lowers confidence on less than 12 months of history
Lead Time Watcher

Reads purchase-order acknowledgments, receipts and supplier email, works out each supplier's actual lead time and flags slips on open orders before the part is late.

  • Never changes a planning lead time without the planner
  • Never contacts a supplier unseen — chases are drafts
Stock Level Setter

Sets min/max per station by MEL criticality — no-go, go-if or go — with the service level, the planning lead time and the repair turn.

  • Proposes only; levels change after approval
Sourcing Planner

For each gap, compares a pool borrow, a transfer from another station, an exchange and a purchase on cost, arrival and risk, and writes the proposal with its reason in one sentence.

  • Never sends a loan request or an order
  • Prefers stock the airline already owns
Proposal Checker

Re-derives the forecast and the arithmetic from raw data, checks the release certificate and traceability terms of every borrowed or bought part, and the approval limit.

  • Cannot approve
  • Disagreement or low confidence goes to a person
Surplus Finder

Finds slow-moving and excess stock, matches it to shortages at other stations, and proposes a move, a sale, a return to the pool or a consignment.

  • Never sells
  • Keeps stock for new deliveries and insurance spares
Fleet Change Planner

Provisions new deliveries against what the airline already holds, and maps an acquired airline's stock to its own part numbers through the parts catalogs' interchangeability.

  • One-way interchangeability always goes to a person
Materials planner and supply chain director

Approve every order; the director co-signs over $250,000. The agents propose; a named person decides.

Ask in plain words

Ask about any part, station or supplier

Ask a question or give an instruction in plain words. The answer cites its sources and can act — open the right screen, or put a proposal on hold with your reason.

Why does O'Hare need 9 brakes?

Eleven brake wear alerts on six ORD 787-9s in 9 days add about 3 likely changes to the 4 that history predicts; flying is up 4%, and four new 787-9s arrive from January. Brakes are no-go, so the agents plan to 9, likely 7.

Which proposals need the director?

One: P-2045, 2 engine-driven pumps for SFO at $284,000, over the $250,000 limit. Halvorsen's slip to Jan 8 is the reason it is needed now.

How much surplus can we sell this quarter?

$24.1M: A320ceo rotables ($11.2M, best bid 61% of book), A320 engine units ($6.4M), 757 parts ($4.1M) and cabin parts ($2.4M). Another $14.5M can move to stations that need it or go to the pool. Trevor Lindqvist approves each.

Hold every A220 order until the Halden stock is merged

Done: P-2043 (3 bleed air valves for BOS, $184,500) is on hold, with your reason logged. Halden's 2 valves of the older -3301 number may cover part of it once Trevor decides on the one-way items. BOS is short from Jan 14 and the lead time is 88 days, so it must be decided by Oct 20.

Every screen

The working solution, as it ships.

13 screens from the working solution, on its sample data. Pick one to see it large.

The stock mapA route map of the airline's stations with each one's shelf against its 30-day need for one part, the proposed pool borrow drawn as an arc, and the conversation with the agents about the station.
TodayThe materials planner's next decision first, shortfalls ahead, proposals waiting by decide-by time, idle stock with a proposal and what each agent found overnight.
Every number opens its sourceThe aircraft health monitoring brake wear report behind the forecast, position by position, with the passage that moved it highlighted.
The part forecastSpare parts demand for 90 days at one station — weekly actuals, the likely line, the range at the service level and the first short day — with each driver cited and the stock level worked out.
Supplier lead timesQuoted against actual lead time per supplier, the planning lead time the agents use, open orders, and the slips read from supplier email this week.
Options comparedA pool borrow, a transfer from another station, waiting for repairs and an AOG spot buy, compared on when each covers the gap, its cost and its risk.
Talking to the agentsThe planner's instruction, the re-planned proposal and the independent check of what it would do to the donor station, with the choice left to her.
Approved and coveredThe approval with its reason, the loan request and purchase order sent only after it, and the station turned from short to covered.
DecisionsEvery borrow, transfer and order proposed, with value, decide-by clock, low-confidence and director co-sign flags, and the small ones that can be approved together.
Fleet health signalsHealth alerts by fleet and system, the forecast each one changed, and the likely sensor fault held out of the forecast until maintenance control confirms.
Surplus stockSlow-moving and surplus aircraft parts with what the agents propose — sell, move, consign or keep — each waiting for the inventory manager.
ResultsAircraft that waited for a part, no-go fill rate, emergency buying and forecast accuracy, measured from the maintenance control log and purchasing, with each miss graded.
Approval rulesThe planner's approval limit, bulk approval, the low-confidence flag, the release certificate rule and the rule that agents never send orders without a person.
Governance

Built for airworthiness and spend: cited, checked twice, signed.

Every number cites its sourceEach forecast, lead time and price links to the health alert, removal record, purchase-order acknowledgment, supplier email, pool agreement clause or price list it came from. Click it to read the passage.
A named person decides, with a reasonEvery borrow, transfer, order, sale and stock-level change is approved, edited or rejected by a named person with a reason code. A rejection's reason goes into the next forecast.
Above the limit, the director co-signsA materials planner approves up to $250,000 per proposal; above it the supply chain director co-signs before anything is released. Bulk approval is only for transfers and pool borrows up to $5,000.
No release certificate, no partAny borrow or purchase without an FAA Form 8130-3 or EASA Form 1 release certificate is blocked, and the Proposal Checker checks the pool agreement's traceability terms for every borrowed part.
Agents never send on their ownLoan requests, purchase orders and supplier messages are never sent without a person. Proposals below 0.80 confidence are flagged for the planner's judgment, and service-level changes need the director.
An audit trail that cannot be editedEvery agent step and every decision is recorded with the time, the reason and the evidence. An evidence pack per proposal holds the forecast, its sources, the checks and the decision.
Configuration

Your stock policy, not ours

Aviation inventory optimization here runs on your stock policy: the service levels, lead-time rule and approval limits the agents plan to are settings. Every change is logged, and stock rules and limits change only when the supply chain director approves.

SettingDefaultChoose from
Service level, no-go parts98%99% · 98% · 95% — proposed by the planner, approved by the supply chain director
Service level, go-if · go · consumables95% · 90% · 85%Editable; changes need the supply chain director
Re-planningNo-go hourly · go-if daily · go and consumables weeklySet by criticality
Plan on actual lead timeOn — 80th percentile of the last 6 receipts when it exceeds the quote by 25%A new supplier lead time is used once the planner accepts it
Planner approval limit$250,000 per proposalAbove it, the supply chain director co-signs
Bulk approvalTransfers and pool borrows up to $5,000Orders are approved one by one
Low confidence0.80Below it, the Proposal Checker flags the proposal for the planner's judgment
Slow-moving threshold12 months without movementStock a delivery in the next 12 months needs is never proposed for sale
Connections

Aircraft spare parts demand forecasting from the systems you already run

Maintenance and engineering systemstock, component removals, the MEL and the check plan
Purchasing (ERP)purchase orders, acknowledgments and receipts
Aircraft health monitoringalerts and wear trends, live
Component pool portalavailability and loan requests
Supplier inboxacknowledgments and supplier email
Flight schedule and fleet planthe flying plan, deliveries and retirements
What it changes

The difference, in numbers.

Every figure is labelled: a target the solution is built to, an estimate, a typical published result, or a proven one.

target
40%fewer
aircraft grounded for a part: 9 a month to 5 in the pilot design
Today9 a month
Target5 a month
estimated
$24Myear one
of idle stock sold or put to use: 16% of $151M slow-moving
of $151M idle stock acted on
surplus spares cost airlines $1.4B in 2025 (IATA)
target
60%less
emergency spot buying, at about 4.8 times the planned price
less spent on AOG spot buys

“demo” = seen in the working solution, on its sample data · “target” = the design goal, measured in the live solution · “estimated” = our estimate (the hours split) · “typical” = published figures (IATA with Oliver Wyman, Oct 2025 — over $11B of supply-chain costs to airlines in 2025, including $1.4B of surplus spare parts holding cost · emergency AOG sourcing at about 4.8 times planned procurement, from published MRO industry data). Rules and forms named: the Minimum Equipment List (14 CFR 121.628) · FAA Form 8130-3 · EASA Form 1. Corvane Airways, Halden Air, Ardent Brake Systems, Halvorsen Hydraulics, Northgate Pneumatics, Meridian Component Pool, the other suppliers and the people named on this page are fictional — characters and sample data in the working solution.

Questions

What airline materials teams ask about aircraft spare parts demand forecasting and spares planning.

What is Aircraft Spare Parts Demand Forecasting?

Aircraft spare parts demand forecasting predicts how many of each part every station will need, and when, so the part is on the shelf before the aircraft needs it. Aircraft Spare Parts Demand Forecasting does it with eight agents that read component removals, health alerts, the flying, check and fleet plans and the supplier's real delivery record, forecast each part at each station for 30, 60 and 90 days, set min/max stock levels and propose a borrow, transfer, order or sale. The materials planner approves, edits or rejects every one.

How do airlines forecast spare parts demand?

In most MRO inventory planning, from removal history in the maintenance system, with min/max levels reviewed once a year. Here the Demand Forecaster uses 36 months of removals and adds what history cannot see: health-driven removals from the Fleet Health Reader, utilization from the flying plan, the check plan and new deliveries. Each forecast is a range with its drivers cited — in the demo, ORD's brakes go from 4 on history alone to 9 at the 98% level.

How are min/max stock levels set for aircraft parts?

The Stock Level Setter reads each fleet's Minimum Equipment List (the MEL, under 14 CFR 121.628 for US carriers) and marks every part no-go, go-if or go, then sets min/max per station from the service level for that criticality — 98%, 95%, 90% and 85% for consumables by default — the planning lead time and the repair turn. It only proposes; a level changes after approval.

Can it prevent AOG caused by a missing part?

It aims to see the shortfall early enough to borrow or move a part. The design goal is 40% fewer aircraft grounded for a part. In the working solution's back-test on 24 months of sample data, 31 of 44 parts-caused ground events would have been seen at least 10 days ahead; 5 had no warning in any data, and the results screen grades each miss.

Does it use the supplier's quoted lead time?

No — it uses what the supplier actually delivers. The Lead Time Watcher reads acknowledgments, receipts and supplier email, and when actual lead time exceeds the quote by 25% it plans on the 80th percentile of the last 6 receipts. A new planning lead time is used once the planner accepts it, and slips on open orders re-plan the shortfalls they affect.

What happens to surplus and slow-moving spare parts?

The Surplus Finder lists stock with no movement in 12 months or more and proposes to sell it, move it to a station whose forecast needs it, consign it or return it to the pool. It keeps anything new deliveries will need and every insurance spare. Nothing is sold, moved or consigned without the inventory manager.

Do people stay in control of what is ordered?

Yes. The agents never send a loan request, purchase order or supplier message on their own. A named planner approves, edits or rejects each proposal with a reason, the supply chain director co-signs above $250,000, and no borrowed or bought part goes ahead without an FAA 8130-3 or EASA Form 1 release certificate.

How long does it take to go live?

The Agentic Solution Engine builds and deploys it from your requirements and documents — your stock policy, MEL criticality, approval limits and a sample of removals, stock and supplier history — and it goes live once every quality gate has passed. We will walk you through it on your own stations first.

See it on
your stations.

We'll run Aircraft Spare Parts Demand Forecasting on your own removals, stock and supplier history.