3 Million NOTAMs Processed: What Affected Elements Reveal

Notamify reached 3,000,000 processed NOTAMs.

At one million, the useful question was how much NOTAM activity we could process and classify. At three million, the question moves closer to the operation itself: which runway, taxiway, service, procedure, airspace, or aid changed, and how often.

The aim behind the analysis is simple: make the operational signal inside NOTAMs easier to use. In Affected Elements V2, a runway closure, fuel outage, CTR restriction, ILS degradation, or PPR carve-out can be reviewed as an affected operational object instead of only read as prose.

We started with the affected objects: taxiways, runways, airspace, approaches, lighting, navigation aids, services, aprons, and aerodromes. Then we asked what happened to each object: restricted, closed, unserviceable, hazardous, cautionary, or work in progress.

What we measured

The dataset contains about two million affected-element exposures. An exposure is one affected object represented by a NOTAM. One NOTAM can affect more than one object, so this count differs from the raw NOTAM count.

Throughout this article, shares refer to affected-element exposures unless noted.

The object is only the start. Context such as aircraft, time window, operation type, altitude, permission, or exception determines whether a notice applies to the flight being planned.

Surface movement carries the largest share

The largest signals are concrete things crews and dispatchers already plan around: taxiways, runways, airspace, approaches, and aprons.

Runway, taxiway, and apron objects together account for 55.7% of the affected-element signal.

A large share of NOTAM impact is surface movement and airport capacity: the route from gate to runway, the runway configuration, the declared availability of surfaces, and the constraints crews absorb before the aircraft leaves the ground.

Most affected elements constrain operations

Separating object from effect changes the analysis. A runway restriction and a runway closure create different planning work. A fuel service outage is different from a limited schedule. An approach can remain available while a required capability is degraded.

Restricted, closed, and unserviceable are the dominant effects. Together, they account for 84.2% of the affected-element matrix.

Runway impact is usually a restriction

Runways are a good example of why this matters.

Restrictions outnumbered closures by nearly four to one.

Closures are decisive. Restrictions are where much of the planning work lives: displaced thresholds, shortened declared distances, work areas, inspection windows, lighting limitations, surface conditions, aircraft-type limits, or other changes that alter the performance calculation.

A restricted runway may still support some operations. The question becomes which aircraft, which configuration, which time window, and which margins remain acceptable.

Airspace disruption can be tracked by place and reason

At FIR, UIR, CTR, and TMA level, the affected airspace stays attached to the effect and reason, which makes disruption visible beyond the individual briefing.

Rocket, space, missile, conflict, and security signals dominate this slice of the airspace dataset. Drone, UAS, GNSS interference, fuel, and smoke-related signals appear as smaller but operationally meaningful clusters.

The ranking is the first layer. A flight ops team can also follow whether a specific FIR, control zone, terminal area, danger area, or restricted airspace object is closed or restricted, and why. That supports network monitoring, alternates, overflight planning, disruption response, and OSINT-style analysis.

Fuel reads as service status

Fuel NOTAMs cover several operational states: no fuel, limited fuel, a specific fuel type unavailable, a supplier closed, hydrant service unavailable, a bowser-only condition, or availability only with prior coordination.

Most fuel-service rows were outages: 68.8% were marked UNSERVICEABLE.

For dispatch, this is airport-service status. If the fuel service is unserviceable, the response is different from a simple restriction, a limited schedule, or a prior-permission condition.

Counts of jet-fuel exposures should be treated as a conservative lower bound, because many fuel NOTAMs describe fuel service without naming a specific fuel type.

Low-visibility capability is a separate operational layer

The largest low-visibility signals were unserviceable navaids and lighting, followed by restricted and unserviceable approaches.

For crews and dispatchers, each of these points to a different planning problem. An ILS, localizer, glideslope, DME, RVR service, PAPI, approach lighting system, or approach minima change can affect alternate planning, dispatch minima, landing performance, and the practical reliability of the route under weather pressure.

This is the kind of signal that disappears inside a long briefing. It becomes manageable when the exact affected object is separated from the surrounding text.

What changes at three million

Three million processed NOTAMs is enough scale for the patterns to stabilize across airports, FIRs, services, procedures, and airside infrastructure.

The more important change is the unit of analysis. The useful unit expands from the NOTAM to the affected object, the effect on that object, and the applicability context that determines whether the change matters.

Across this run, surface movement objects dominate the affected-element signal. Constraints and outages dominate the effect mix. Runway impact is usually a restriction rather than a closure. Airspace disruption can be followed by affected identifier and reason. Fuel is largely an airport-service outage signal. Low-visibility capability depends on many small equipment and procedure states that text alone tends to flatten.

The milestone is the number. The value is that the NOTAM stream becomes measurable: what changed, where it changed, how severe it is, and who it applies to.

If this is the kind of signal you need operationally, check Notamify Alerts to get important NOTAM first, by email.