How to Handle AOGs: An Airline's Perspective

You're no stranger to an AOG. You despise them. They make you sweat. They make you mad. They may even make you cry.

No matter how much work engineers and technicians put on the aircraft, or how much time you spend planning, AOGs still occur. There’s no luck involved. They’ll happen and we’ll need to fix it. 

Anything is possible. It’s madness I tell you!

Skylink, AOG

Skylink, AOG

The biggest challenge is getting the right aircraft part and having an expert solution backing you up as fast as possible. Every minute counts.

An AOG is an emergency, but there's different priority levels.

I like to call "real" AOGs term AOGs. Your aircraft is on the ground now. It’s losing money every minute it sits. These are the palm sweating, I’m super stressed moments.

Sometimes we still call AOGs that aren't quite grounded yet--for whatever reason. A good example is a flight not scheduled again for 7 days, or there’s only 14 days left in the C check and now we’re “AOG”. The term is used to incite panic. People are getting stressed and the time frames are getting cut close. These AOGs I like to refer to as pre-term AOGs.

Both are still problems and both cost time and money.

All operators must have an AOG strategy.

How to plan your Aircraft on Ground (AOGs)

When you plan for possible AOG situations, it's important to keep a few variables in mind. As you know, these situations can vary far and wide, but starting with these variables is good.

The 3 variables are:

  • Knowing critical and no-go items.
  •  Locations where your aircraft flies.
  •  Frequency of flights.

Now that you've considered these, you can begin to plan for your AOGs.

In the beginning it starts with aircraft material readiness and a recommended spare parts list

The entire planning process starts with identifying critical parts. When you're inducting a new fleet, you'll get this during the material readiness process.

aircraft parts, aircraft component pooling

aircraft parts, aircraft component pooling

The document provided by the manufacturer, you know, Boeing, Airbus, Embraer, ATR, outlines all the parts and material installed on your fleet. It categorizes them as no-go, go-if and go items, and shares critical information as MTBUR (mean time between unscheduled removal), QPA (quantity per aircraft), lead time for ordering, mean shop processing time, among other "necessary" calculations. After all that you'll finally receive a spare float quantity required to ensure smooth operation of the aircraft.

Seems simple, right?

Airline experience

History is important. I know, bummer for you new operators reading this.

When you're able to administer a tracking system, it's easier to identify frequency of removals for critical material and use during your AOG planning process. You'll then need to establish your history of how long it'll take to get from your base station to your AOG location. The larger the fleet, the more routes you have, the more complicated this gets.

Once you have the experience, you'll have a better idea of what components you need more often and what logistical methods you'll take to alleviate the AOG.

Borrow or own your material

After that you determine what aircraft parts you need and where they need to be, it's now time to allocate your resources (money) to the right strategy.

The most important decision you'll make is to own or borrow your material and how you'll transport them in case of an emergency.

Flyaway kit

Some airlines maintain a flyaway kit, This kit holds important items that have a high chance of becoming faulty. They're immediately available during groundings at outstations.

The airline can own these items, or they can work with a material partner to provide these kits.


Airlines then develop partnerships with companies operating at stations where they have flights (frequency of flying is a key determinant). Most important among these is to have arrangements with other airlines operating from/to a given station. Of these, the best partner is the airline which is based in that station or operates from the same country (and maintains a similar fleet).

This is for AOG planning only. You don’t share the same inventory and you only rely on them to support your material needs.

Aircraft Material Partner

Aircraft Material Partner

It’s true airlines are competing companies. But it’s an unmarked rule that they support each other in times of need, especially when an AOG situation occurs. Through industrial platforms such as IATP (International Airline Technical Pooling), airlines have maintained a longstanding gentlemen's agreement to support each other in times of need. Airlines develop bilateral loan and borrowing arrangements at a pre-determined rate. They participate in pooling arrangements for a defined set of critical items, paying a minimal amount per year, getting support in an AOG situation.

There are good pooling options out there. Just be careful. I see a lot of contracts happen and the contracting partner makes things difficult.

Airline capital is expensive, and there are great options available from experts who only focus on material and supply chain solutions. This is all they do, all day long.

It's really about finding the best fit strategy for your unique operation.


Cannibalization or robbing a unit from an aircraft grounded for maintenance is another option. This helps get the AOG aircraft back in the air and the material can be sourced for the routine maintenance aircraft.

When all else fails

The techniques mentioned are all prior to AOG planning, and are found to be very effective in minimizing the impact of AOG situations. Even then, situations happen that even the best planning is not good enough.

During these situations you have to adopt a number of approaches to get the support you need and fast.

Here are some more ideas:

  • Borrow or take a unit on loan. The quick fix solution for an AOG involving lesser cost impact (procuring a unit on an AOG basis can be costly). The first to approach are airlines, handling agencies, MRO’s located at the station of AOG. Then you look around the country, and then in the given region.
  • Getting your unit on exchange can also be a good solution in a time of need. Also, airlines can use trading platforms to source a unit in demand or call a trustworthy material partner.
  • When all else fails, airlines approach OEM’s, airline manufacturers, distributors and suppliers to procure the desired unit. This involves higher cost but cost becomes secondary in AOG situations.

The moral of the AOG story is: plan right, use trustworthy partners and resolve AOGs fast. We can't escape them, so we'll tackle them one AOG at a time.

Do you have an AOG story? Please do share below...

This post was brought to you by Irfan Alam. He’s an aircraft engineer for Pakistan International Airlines and has expertise in technical contracts, rotable planning, and provisioning.