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Traditional airport surface management provides limited ability for controllers to anticipate aircraft movements, resulting in suboptimal route assignments that contribute to conflicts, delays, and increased fuel consumption. With continued growth in air traffic demand, these operational inefficiencies are expected to become increasingly significant.

To address these issues, surface trajectory-based operations (STBO) have been proposed, enabling air traffic controllers to preplan and optimize aircraft trajectories. For STBO to be effective, aircraft movements must be fully predictable: pilots must conform to assigned speed profiles along their route to and from the runway, thereby reducing positional uncertainty. This fundamentally changes how flight crews operate and requires new guidance systems.

Visual guidance interfaces have been investigated, continuously indicating where the aircraft should be along its route according to the assigned speed profile. These systems allow pilots to track their target position while remaining within a 250 meter allowable deviation band. However, most simulation studies demonstrating the potential gains of STBO in reducing fuel burn and delays assume tighter spacing between aircraft, revealing a discrepancy between optimization targets and currently achievable human performance. Indeed, such reduced tolerances have been shown to result in more frequent loss of conformance—triggering costly reroutings—and excessive attention to the display (head-down time)—a significant threat to safety. These issues highlight a key gap: current guidance techniques are insufficient to safely support pilots at the level of precision required to fully realize the potential of STBO.

This thesis proposes improved STBO guidance systems designed to enable pilots to safely conform to reduced deviation bands. Based on a cognitive task analysis of pilots' information requirements for STBO, we identified ways to support situation awareness, improving performance by enhancing their ability to perceive, understand, and anticipate relevant operational constraints. The task analysis highlighted an opportunity to support the highest level of situation awareness (anticipation) by conveying future changes in trajectory speed. To explore this, we investigated visual representations of trajectory speed that are glanceable—minimizing head-down time—while still conveying a complete and accurate picture of the speed profile. We found that an appropriate representation improves conformance to reduced deviation bands but does not reduce excessive head-down time.

To address this remaining limitation, we explored the use of haptic cues delivered directly through the speed control interface, i.e., the thrust lever. Among the cue types evaluated, we found asymmetric vibrations to be the most effective for conveying thrust commands.

An improved STBO support system, combining visual trajectory speed representations and haptic thrust cues, was evaluated with professional pilots. Conformance to a 100 meter deviation band—representing the average deviation used in STBO simulation studies—increased from 84% with existing guidance systems to 90% with trajectory speed symbology and to 99% with the addition of haptic cues. Furthermore, head-down time decreased from 38% with current guidance systems to 27% when haptic cues were introduced.

This thesis contributes to the implementation of STBO and the associated reductions in delays and fuel burn by improving pilot conformance, paving the way for safer and more efficient airport surface operations."