How do you spec a passenger boarding bridge — apron-drive vs fixed, glass vs steel, single vs dual?

A passenger boarding bridge (PBB) is a longlived, expensive piece of fixed infrastructure, and the specification choices made at purchase — drive type, tunnel material, reach, and single versus dualbridge — lock in…

A passenger boarding bridge (PBB) is a long-lived, expensive piece of fixed infrastructure, and the specification choices made at purchase — drive type, tunnel material, reach, and single- versus dual-bridge — lock in which aircraft a stand can serve and how it ages for decades. This brief is about those selection decisions for a terminal planner or procurement team, not a general explainer of how jet bridges work. The leading manufacturers you will evaluate are TK Elevator (formerly thyssenkrupp), Oshkosh AeroTech (the Jetway PBB line, formerly JBT AeroTech), ADELTE and CIMC.

Decision 1: Apron-drive vs fixed (nose-loader)

This is the first and most consequential choice, because it sets how much of the apron the bridge can reach.

	Fixed / nose-loader	Apron-drive
Movement	Telescopes in/out from a fixed pivot; little lateral sweep	Drives across the apron on a wheel bogie; large sweep area
Aircraft flexibility	Limited — best where door positions are predictable	High — reaches multiple door positions and a wide aircraft mix
Cost	Lower	Higher
Best for	Simple stands, narrow aircraft mix, lower traffic	Busy stands serving a diverse fleet; multi-type gates

An apron-drive bridge starts from a rotunda fixed over a column anchored to the ground, with the tunnel carried on a wheeled bogie (the traction system) and raised on twin steel elevation pillars, giving it the sweep to serve many aircraft positions. A fixed/nose-loader bridge has far less sweep and suits stands where the aircraft and door position vary little. Choose apron-drive when the stand must serve a broad aircraft mix or high traffic; choose fixed when the aircraft mix is narrow and budget is the priority.

Decision 2: Glass vs steel tunnel

Tunnel construction has been shifting from traditional all-steel to a steel frame with glass panels, and the choice is a real trade-off, not just aesthetics.

Glass-panel tunnels (glass side walls in a diagonal steel-tube frame) give passengers daylight and a modern terminal feel, and are increasingly the premium default. Glazing can be specified as single template, NFPA 415-compliant, or even bulletproof depending on the security and fire requirement.
Steel tunnels are more robust, simpler and cheaper, and shrug off impacts and weathering.

In Gulf-climate operations the glass choice carries a thermal cost: large glazed areas admit solar heat, raising the cooling load inside the tunnel. If you specify glass for the passenger experience, also specify appropriate solar-control glazing and ensure the bridge's air conditioning is sized for the heat gain — otherwise the tunnel becomes uncomfortably hot on a summer afternoon.

Decision 3: Reach, height and A380 / Code-F capability

A bridge must physically reach the aircraft's doors, and large aircraft push the envelope. An A380 apron-drive bridge must elevate higher than a normal bridge — up to around eight metres — to reach the upper-deck and main-deck doors, and that extra height demands extra structural strength, which in turn adds cost. The rule for procurement: size reach and elevation for the largest aircraft the stand will regularly serve, not the average, and confirm the bridge is certified for that type. Specifying a Code-F-capable bridge on a stand that will only ever see narrowbodies wastes capital; under-specifying on a stand that must take A380s strands the aircraft.

Decision 4: Single vs dual (and triple) bridges

The number of bridges per stand follows the aircraft and the turn-time target.

Single bridge — adequate for narrowbody and most widebody stands where one door handles boarding within the turn-time target.
Dual bridges — used to speed boarding/deboarding of large widebodies by working two doors at once, cutting turnaround time on high-utilisation stands.
Triple / multi-door bridges — associated with the A380, where serving both the main and upper decks (and multiple doors) simultaneously is what makes the turn time achievable for ~500+ passengers.

The decision is economic: more bridges per stand cost more capital but cut minutes off every turn. On a high-frequency A380 or widebody stand those minutes compound across the day; on a low-frequency stand they do not justify the second bridge.

Decision 5: Drive and elevation system

PBBs use either hydraulic or electro-mechanical drive and elevation systems. Electro-mechanical systems are generally cleaner (no hydraulic fluid), quieter and lower-maintenance, and are the common modern default; hydraulic systems remain in service and are well understood. Treat this as a maintenance-philosophy and total-cost choice rather than a capability one.

GCC relevance

Gulf hubs (DXB, DOH, AUH, JED, RUH) combine flagship A380/Code-F operations with dense widebody and narrowbody traffic, which pushes specifications toward apron-drive bridges with high reach, dual or triple configurations on the marquee widebody stands, and glass tunnels for the premium passenger experience — with the explicit caveat that glazing must be solar-controlled and the bridge HVAC sized for extreme heat. The same heat argues for electro-mechanical drive and robust, heat-rated components throughout.

Honest limitations

PBB selection is stand-specific: the right answer for a flagship A380 gate is wrong for a remote narrowbody stand, and over-specifying every stand to the worst case wastes capital. Glass tunnels and dual/triple bridges are premium choices justified by passenger experience and turn-time economics, not universal upgrades. Always confirm type certification and structural rating for the specific largest aircraft a stand will serve, and validate HVAC sizing against local summer conditions — vendor nominal ratings are often quoted for temperate climates.

The bottom line

Spec apron-drive for flexible, busy, multi-type stands and fixed/nose-loader only for narrow, low-traffic ones. Choose glass for passenger experience but pay for solar-control glazing and bigger HVAC in the Gulf. Size reach and elevation for the largest regular aircraft, add dual/triple bridges only where turn-time economics justify them, and prefer electro-mechanical drive for lower maintenance. Match the spec to the stand — never spec every gate to the A380 worst case.