Piloted simulation of NextGen time-based taxi clearances and tailored departures

This paper describes the results of a medium-fidelity piloted flight deck simulation of future surface operations. Sixteen commercial transport pilots conducted time-based taxi-out operations at DFW airport under two next generation airspace (NextGen) implementations. In the limited NextGen implementation, time-based operations were defined by providing a taxi clearance with a commanded average speed to the pilot. In the advanced NextGen implementation, advanced avionics allowed for time-based taxi operations to be conducted with speed error-nulling algorithms and arrival time information. Results indicated that the Advanced NextGen implementation substantially improved pilots' ability to arrive at airport traffic flow points at the required time. An additional ldquotailored departurerdquo (i.e., NextGen 4-D departure) clearance verification task assessed the impact of time-based taxi on the departure phase of flight. Results indicated that time-based taxi operations in general, and specifically the advanced NextGen implementation, might add to pilot workload during taxi out. Future research regarding the assessment and the impact of time-based taxi operations is required.