Ratan Khatwa

Flight simulator evaluation of pilot performance with the runway awareness and advisory system (RAAS)

This paper provides an overview of a human factors evaluation to objectively assess pilot performance and the operational safety benefits of the runway awareness and advisory system (RAAS). This evaluation was the last one of a series that formed a critical element of the iterative design process adopted to develop the RAAS. The purpose of the RAAS is to enhance flight crew position awareness during aircraft surface operations and on final approach. Factors such as effect of RAAS on pilot spatial (position) awareness, decision-making, workload, overall pilot acceptability and ease of learning the RAAS functionality were evaluated. A non-RAAS group served as the reference group A Boeing 737-400 flight simulator was used in a between-subjects experiment design. Crews were subjected to a range of operational scenarios that included both normal and, non-normal conditions associated with runway incursions. Evaluation data show that RAAS improved pilot position awareness during surface operations and on approach to landing. RAAS resulted in earlier pilot recognition of potential position awareness related conflicts. Furthermore, RAAS improved pilot decision-making and did not increase workload. There were no RAAS-induced crew errors observed in any of the scenarios. Subjects were able to satisfactorily complete all flight deck tasks, execute crew procedures and crew co-ordination associated with all scenarios with the aid of RAAS. Ratings for overall pilot acceptability and learnability of RAAS were very favorable. Overall, these data indicate a favorable impact of RAAS on crew performance and operational safety.

Human Centered design of an In-Trail Procedures (ITP) system

This paper provides an overview of a development program to design and certify an In-Trail Procedures (ITP) system for the Boeing 747-400 aircraft. ITP offers aircraft broader flexibility to change flight levels during oceanic flight. The classical elements of a Human Centered Design (HCD) process were integrated within a commercial systems engineering process to develop the system. Previously reported user difficulties in formulating ITP clearances, design challenges posed by touch screen user interfaces and retrofit avionics architecture, as well as the associated certification challenges were addressed during the program. Data from both simulator and in-flight evaluations confirm that pilots are able to perform the intended function under a broad range of operational conditions. The ITP system has undergone successful certification and is operational on a Convair 580 and Boeing 747-400 aircraft.

Flight simulator evaluation of an Airport Surface Display with Indications and Alerts (SURF IA)

This paper presents the results of a flight simulator evaluation of an Airport Surface Display with Indications and Alerts (SURF IA). The objective was to investigate the independent effects of display type on traffic conflict detection. The study included a comparative evaluation of a Cockpit Display of Traffic Information with Indications & Alerts (CDTI IA) and CDTI without IA (CDTI baseline). Eight commercial airline pilots each flew nine scenarios in a B737–700 part-task flight simulator. Dependent measures included both subjective and objective data. The display symbology for traffic and runway indications and alerts was acceptable and understood by the pilots. The traffic velocity trend vector was considered a significant cue with which to detect traffic conflicts. Workload was perceived as acceptable for both CDTI types. There was no significant difference in traffic conflict detection rates between CDTI baseline and CDTI IA groups. However, the CDTI IA facilitated faster conflict detection and decision making during final approach scenarios when compared to the CDTI baseline display. Similar differences were not observed for take-off scenarios, primarily due to the absence of an alert: either the scenario did not progress to a point where an alert was generated, or the alert was inhibited above 80 knots per the system design.