Evolution of Electronic Approval Request Procedures at Charlotte Douglas International Airport

At many major U.S. airports, a departure approval request, or `APREQ,' establishes a later runway departure time for a flight, allowing it to absorb tactical delay on the ground. APREQ times are traditionally coordinated by a process known as `call-for-release' whereby an airport surface traffic manager calls an airspace traffic manager on the telephone. This research examines new electronic APREQ coordination enabled by the NASA Airspace Technology Demonstration-2 system and compares it to the call-for-release method of coordination. During the initial deployment period, electronic APREQ coordination was used for more than half of eligible flights. A majority of electronic requests were approved in less than one minute on average. Data suggest that both the average tactical delay and compliance with the electronically coordinated departure times did not differ significantly from departure times coordinated using call-for-release.