The CUSS Handbook / What common use actually means
What common use actually means
“Common use” is one of those terms that gets applied loosely enough to stop meaning anything. It has a specific sense in airport operations, and it is worth pinning down before anything else on this site will make sense.
The definition
Common use describes airport equipment that is owned or controlled by one party — usually the airport operator, sometimes a service provider — and made available in turn to many airlines, each of which runs its own software on it. The equipment is shared. The applications are not. A passenger at a common-use kiosk chooses an airline from a launch screen, and the airline's own check-in application takes over the screen and the attached devices for the duration of that transaction.
The critical word is in turn. Common use is sequential occupancy of a shared physical resource, mediated by a platform that both parties trust. It is not a single generic check-in application that all airlines agree to use. Nobody has ever succeeded in getting airlines to agree on that, and the standard does not ask them to.
Common use, shared use, dedicated
Three arrangements are usually distinguished, and the boundaries matter commercially more than technically.
- Dedicated equipment belongs to one airline and runs only that airline's software. A home carrier's own check-in row is the classic case. It is simple, it is fast to change, and it is idle whenever that airline is not operating a bank of departures.
- Common use equipment belongs to the airport or a provider and is offered to any carrier that has certified software for the platform. Utilisation goes up, per-airline capital cost goes down, and the airport gains the ability to reallocate hall space as schedules change.
- Shared use is a term the industry uses somewhat interchangeably with common use, but it also has a precise regulatory meaning in the United States. Under the US Department of Transportation's air travel accessibility rule, a shared-use automated airport kiosk is one jointly owned, controlled or leased by an airport operator and carriers and/or an independent service provider. That definition matters because it determines who is liable for making the machine accessible — see kiosk accessibility requirements.
The problem it solves
Terminal floor space is the scarcest thing an airport has, and it is fixed for decades at a time. Passenger numbers are not fixed, schedules change seasonally, and the mix of carriers in a hall changes on a timescale of years. Dedicated equipment locks physical space to a commercial relationship, and the lock is expensive to break: moving an airline means moving its counters, its kiosks, its cabling and its signage.
Common use decouples the two. If the equipment in a hall is generic and any certified airline application can run on any unit, then reallocating a hall becomes a scheduling exercise rather than a construction project. That is the airport's business case, and it is a large one: it defers terminal expansion, which is the single most expensive thing an airport ever does.
The airline's business case is different and needs stating separately, because a deployment that only serves the airport's interest tends not to get adopted. For a carrier, the appeal is that one certified application can be deployed at every common-use airport in the network without a bespoke integration at each one. The integration cost is paid once. Against that, the airline gives up control of the hardware and of the passenger's first impression, which is a real cost and is the usual source of resistance.
What common use is not
A few persistent misconceptions are worth clearing.
It is not a check-in application. The standard defines how an application gets access to a kiosk. It says nothing about how an airline checks a passenger in, what its fare rules are, or how its screens should look. Two carriers on the same kiosk may have completely different flows.
It is not only kiosks. Self-service kiosks are the most visible case, but the same idea covers shared check-in desks and gate podiums — that is the CUPPS side of the family — and increasingly bag-drop units and boarding gates.
It is not automatically cheaper for everyone. Common use moves cost around: capital from airlines to the airport, integration cost from many to one, and operational responsibility onto whoever runs the platform. Whether it is cheaper in a specific terminal depends on the carrier mix and on how the recharge model is written, which is why evaluation deserves proper attention rather than a spreadsheet of unit prices.
It does not remove the airline's obligations. A carrier using a shared kiosk is still the carrier. Accessibility duties, data protection duties and the passenger relationship all remain with it, which is precisely why the US rule makes carriers jointly and severally liable with airport operators for shared-use kiosk compliance.
Where the standards fit
Two published Recommended Practices carry most of the weight. CUSS covers self-service devices — the kiosk a passenger operates alone. CUPPS covers staffed positions, meaning check-in desks and gate podiums where an agent is the operator. They developed separately, they solve related problems, and an airport of any size will typically run both. IATA publishes and maintains them, and its common use standards page is the canonical index of what currently exists and at what version.
Alongside them sit narrower specifications for the things a common-use device has to do: bar coded boarding passes, baggage messaging, and web-services interfaces for functions such as bag drop, identity management and boarding. The glossary maps the acronyms.