# Airport Operational Flows Airport operations is not one optimization problem. It's five coupled flows that must be coordinated simultaneously. Optimizing any one in isolation sub-optimizes the whole. ## Aircraft Flow Approach, landing, taxi-in, docking, on-blocks, turnaround (dwell), off-blocks, pushback, taxi-out, takeoff. This is the flow that [[Aircraft Turnaround]], [[Stand and Gate Allocation]], and [[Ground Support Equipment Scheduling]] address. The airside domain. ## Passenger Flow (Departure) Check-in, baggage drop-off, security screening, border control, lounge/dwell, pre-clearance, gate hold, boarding. See [[Passenger Flow Optimization]]. The terminal domain. ## Passenger Flow (Arrival) Arrival at pier, border control, baggage reclaim, customs, landside departure. Mirrors the departure flow but with different bottleneck physics: the constraint shifts from screening throughput to immigration processing speed and baggage system delivery time. ## Baggage Flow Transport from aircraft, unloading, transfer sorting, storage, reconciliation, loading and weighing, transport to aircraft. Baggage has its own optimization problem with hard deadlines (the aircraft departs whether the bags are loaded or not) and complex routing for transfer connections. ## Cargo Flow Distinct from baggage. Cargo moves on its own timeline: transport to/from warehouse, breakdown or build-up of unit load devices (ULDs), customs clearance, dangerous goods screening, cold chain management for perishables, acceptance and documentation. Cargo operates 24/7 while passenger operations cluster in peaks. The interaction: cargo and baggage share belly space on passenger aircraft, so cargo loading competes with baggage for the same physical constraint (aircraft hold capacity and loading time window). Freighter operations add dedicated stands, separate ground handling, and different turnaround profiles. Most passenger-focused optimization systems ignore cargo entirely. That's a blind spot when belly cargo revenue can be 5-15% of an airline's revenue on a given route. ## The Transfer Coupling The fifth coupling. A passenger connecting between flights must clear security, border control, and potentially baggage re-check within a connection window set by the stand allocation of both the arriving and departing aircraft. This creates a feedback loop between airside decisions and terminal throughput. Transfer baggage adds another layer: bags must be physically moved between aircraft within the same connection window, through sorting systems that serve all flights simultaneously. Hub airports with 40-60% transfer traffic live and die by this coupling. The minimum connection time (MCT) published by airlines is a promise made by the commercial team that the operations team must deliver. ## The Core Insight [[Total Airport Management]] exists because these five flows need joint visibility and coordinated decision-making. Today, most airports optimize aircraft flow and passenger flow through completely separate teams, separate systems, and separate KPIs. Related: [[Airport Operations MOC]], [[Aircraft Turnaround]], [[Stand and Gate Allocation]], [[Passenger Flow Optimization]], [[Total Airport Management]] --- Tags: #deeptech #systems