Speed control on RNAV OPD for near-term ATM TRACON operations

The use of RNAV procedures in the terminal area coupled with optimal profile descents (OPD) is showing promise as a viable near-term step towards full blown NextGen trajectory based operations. A strong point of RNAV OPD operations in the TRACON is that they can be performed with existing avionics capabilities as most modern transport aircraft have Flight Management Systems (FMS) capable of RNAV and Vertical Navigation (VNAV). In fact, such an operation is currently being considered by the FAA as a candidate for extension of 3D Paths in Arrival Management (3D PAM) operations through the TRACON. The objective is to determine how controllers and pilots can support this RNAV-based operation with little or no reversion to manual vectoring, even in complex high-density airspace. This paper examines the use of speed intervention during an RNAV procedure as a means of ensuring safe spacing through terminal area merge points, while executing OPD procedures.