When the Aircraft Is AOG, Who Gets the Part First?by Editor - Daniel Brindley | September 6, 2026

There’s nothing worse than an AOG caused by a part that should be straightforward but isn’t.

Take an aircraft window for a leading mid-to-large business jet. The aircraft may be serviceable otherwise, but a cracked or delaminated window that affects the pilot’s visibility can keep it on the ground.

The first call will probably go to the aircraft OEM or its authorized distribution channel. If the window is backlogged, the search expands to brokers, listing sites, repair sources, and teardown companies.

At that point, the question isn’t simply, “Who has the window?”

The real question is, “Who has the best route to the window, and what will it take to get that part released?”

AOG priority usually comes with conditions

I once received a call about an aircraft that was down and needed one of these hard-to-find windows.

I had a relationship with the aircraft OEM, even though it wasn’t the actual window manufacturer. As a major customer of the manufacturer, the OEM had more leverage and better visibility into the production schedule than an individual operator or broker normally would.

Under normal circumstances, the lead time for the window was approximately 12 months. However, there was an arrangement that allowed the OEM to obtain one sooner for a legitimate AOG requirement.

There was a condition: the customer had to provide evidence that the installed window was cracked or delaminated and that pilot visibility was in question.

That information was valuable. In this case, we obtained the window.

It also showed that declaring an AOG isn’t always enough. The request may need photographs, the aircraft serial or registration number, the installed part number, the maintenance squawk, and a description of the defect.

The OEM or distributor may also want confirmation that the part is for an installed aircraft and isn’t being purchased for inventory or resale.

The buyer who can quickly provide the required aircraft details, photographs, and proof of the AOG may have a better chance of getting the part sooner.

Relationships affect access to information

In a shortage, different sellers see different parts of the market.

The aircraft OEM may have access to production allocations that aren’t visible to independent buyers. An authorized distributor may know about inventory moving between warehouses. A broker may know about a part sitting on another operator’s shelf. A repair station may have a serviceable unit approaching completion. A teardown company may know that the correct part is still installed on an aircraft waiting to be dismantled.

That’s why an accurate lead time can be almost as valuable as the part itself.

There’s a big difference between being told “12 months” and learning that an AOG allocation may become available in ten days if the operator submits the right evidence. There’s also a difference between a teardown company saying it has the part and confirming when that part will be removed, inspected, documented, and ready to ship.

A part isn’t available just because someone knows where it is.

Legacy aircraft create a different problem

On older or legacy aircraft, there may be no AOG production option.

The manufacturer may no longer produce the part regularly. Tooling may have been retired, minimum quantities may apply, or the original supplier may have changed. A part may technically remain available, but its lead time won’t help an operator that is already grounded.

That’s when the secondary market takes over.

If only a few sellers have the required window, they can dictate the price. A part that would normally be purchased through the OEM channel may appear in the aftermarket at four times the normal OEM price.

Buyers understandably push back against paying that much. But the comparison isn’t only between the seller’s price and the OEM list price. It’s between the available part and the total cost of leaving the aircraft grounded.

That calculation will be different for a private owner, charter operator, flight department, or aircraft dealer.

The search quickly becomes global

Once the normal channel fails, the search becomes global and every credible source comes into play.

The fastest quote isn’t necessarily the best solution. The buyer still needs to confirm the exact part number, modification status, aircraft applicability, condition, trace, release documentation, location, and realistic shipping time.

A seller may have a serviceable part, but its documentation might not meet the operator’s requirements. The part may have incomplete trace, an unacceptable repair history, or a configuration that doesn’t match the aircraft.

Shortages create pressure, but they don’t remove the need to establish that a replacement part is eligible and properly documented. FAA guidance points buyers toward supporting records, identification, and traceability when evaluating replacement parts and suspected unapproved parts.

A teardown part isn’t ready until it’s ready

Teardown aircraft can provide solutions for older fleets, but the timing is frequently misunderstood.

The required part may still be attached to an aircraft that is weeks away from being dismantled. After removal, it may need inspection, testing, repair, or overhaul before it can ship with the appropriate documentation.

There may be competing demand. If several buyers want the same part, the teardown company may require a deposit or firm purchase commitment before prioritizing its removal.

The buyer needs to ask whether the part has been removed, what condition it is in, who will inspect or repair it, what documentation will accompany it, and whether a shop slot is available.

A promise that the part is “coming off an aircraft” is not the same as having a serviceable unit ready for dispatch.

Damaged parts and cores can become viable options

Sometimes the only available asset is a damaged unit or repairable core.

The part has to be evaluated to determine whether it is technically repairable and whether repairing it makes economic sense. There may be damage beyond published repair limits, replacement material may be backlogged, or specialized outside processing may be required.

The commercial question is straightforward: what will it cost to acquire and repair the core compared with its known market value and the cost of the aircraft remaining down?

If the core is in good condition and the customer authorizes expedited work, it may be possible to obtain a usable part faster than a standard 30-day repair turnaround. That depends on shop capacity, material availability, inspection findings, applicable repair data, and the buyer’s ability to approve additional charges.

A core can be found quickly and still sit in the shop because nobody has authority to approve the revised quote.

AOG procurement is also decision management

The best AOG buyers don’t just search faster. They remove delays from the decision process.

Before the quotes arrive, they know what condition and documentation they will accept, whether an exchange or repaired unit is an option, who can approve a premium purchase, and whether an international purchase creates import or export complications.

They also make sure the RFQ is complete. An incomplete request can waste hours while sellers ask for the aircraft serial number, installed part number, modification status, required condition, paperwork requirements, delivery location, and core availability.

When the market is tight, a seller may receive several inquiries for the same part. The buyer who can confirm the requirement, review the documents, provide payment, and arrange shipping is in a stronger position than a buyer still trying to determine whether the part will work.

Availability is more than an inventory count

An aircraft part is only truly available when it has the correct configuration, acceptable condition and records, a workable delivery date, and terms the operator can approve.

A window sitting in a warehouse may solve the AOG tomorrow. A cheaper window expected from the OEM next year won’t.

A core may be the fastest answer, but only if it can be repaired. A teardown part may look promising, but only if it comes off the aircraft on schedule and passes inspection.

That’s what parts shortages have changed. Procurement is no longer just about finding a part number and comparing three quotes. It’s about knowing where the leverage is, what questions to ask, what documentation to have ready, and when paying a premium is less expensive than continuing to wait.

This article describes a real-world aviation maintenance situation. Company and individual names have been withheld to respect commercial confidentiality, and certain nonmaterial details have been generalized.