Satellite and midfield concourses

How does Satellite and midfield concourses work, step by step?

1. 1

   Step 1: Justify the configuration and fix the connection strategy

   The airport operator decides between extending piers and building a satellite on the basis of apron capacity, aircraft manoeuvring, connection times and the growth it forecasts. The connection strategy is settled at the same time, because it drives the cost and the programme: an automated people mover in tunnel, a people mover on a viaduct, a walking tunnel, or buses. Once chosen it is effectively permanent, so the decision considers the capacity needed decades ahead rather than at opening.

2. 2

   Step 2: Coordinate with airfield operations before design is fixed

   A midfield site sits inside the operational airfield, so the design has to work around runway and taxiway clearances, obstacle limitation, navigation aid protection and emergency access, all set by the airport operator and the aviation regulator. Construction height limits, crane oversail restrictions and permitted working hours come out of that coordination, and they shape everything from the structural form to the choice of erection method. These constraints are established before the design is committed.

3. 3

   Step 3: Build the connection tunnel or viaduct

   The connection is usually the longest lead item on the project. A tunnel beneath live taxiways and runways means settlement control, monitoring of the surface above and working within movement limits the operator will not relax. A viaduct means lifting over or beside operational areas, generally at night. Either way the connection is programmed first, because the concourse cannot open without it and it cannot be accelerated at the end.

4. 4

   Step 4: Establish the site and the logistics route out on the airfield

   The construction site is fenced and secured within the airfield, with its own access route, escorting arrangements and vehicle discipline. Every worker needs airside clearance and every vehicle needs a permit and often an escort. Deliveries are scheduled around movements, and the logistics of getting materials and people to a site in the middle of an airfield become a major cost that has no equivalent on a landside project. Foreign object debris control is enforced continuously, not periodically.

5. 5

   Step 5: Bring the utilities and the baggage connection out to the site

   Power, water, drainage, communications, fire mains, fuel and the baggage transfer route all have to reach the concourse, usually along the same corridor as the passenger connection. Those services are installed early and are frequently on the critical path, since crossing a live taxiway with a service duct needs its own closure and its own reinstatement of the pavement above. Capacity for future expansion is built into the corridor now, because reopening it later is far harder than sizing it generously today.

6. 6

   Step 6: Construct the concourse structure and envelope

   The building itself is a gate concourse: a long-span or repetitive structure with lounges, circulation, retail and services. Erection methods are constrained by the height limits and the working hours the operator imposes, which often favours ground assembly and short high-consequence lifts over long periods of working at height. Materials arrive by escorted convoy, so laydown on site is planned carefully and deliveries are batched.

7. 7

   Step 7: Install the people mover and the concourse systems

   The automated people mover vehicles, track, power, signalling, platform doors and control systems are installed and integrated, along with the concourse baggage transfer, fire and smoke control, security and communications systems. Systems integration between the concourse, the connection and the main terminal is the hardest part, because a passenger journey now crosses two buildings and a transit system that were procured separately.

8. 8

   Step 8: Commission the whole journey and prove the failure modes

   Commissioning covers the entire journey from the main terminal to the gate and back, including what happens when it goes wrong. The evacuation strategy for a detached concourse, the arrangements when the people mover fails, the emergency access route for the fire service, and the way passengers are recovered from a stalled transit are all proven with the operator before opening. Trials involving volunteers and the operator's own staff are the final gate before the concourse enters service.