Trajectory-Based Operations (TBO) - Joint Planning and ...

Trajectory-Based Operations (TBO)
Study Team Report
17.10 Arrival/Approach and Landing TBO Automation
This automation replicates all the functions first described for departures, and integrates the exchange
of information relating to arrivals to the surface movement TBO automation. The capabilities are
highly coupled with en route TBO automation.
The big difference between the arrival/approach and landing TBO automation and en route TBO
automation is the number of tools available to manage sequencing, and merging and spacing for OPDs,
closely spaced parallel runway operations, wake turbulence spacing, and mixed equipage in the arrival
streams. The information exchange between en route TBO automation and arrival/approach and
landing TBO automation is essential for setting TOD due to the fact that this sequencing happens well
into the cruise phase of flight, and is updated as aircraft get closer to their TOD position and time.
There is a limited amount of time that can be gained or lost from TOD to touchdown. 25
Arrival/approach and landing TBO automation is continuously updating the landing sequence based on
the flight object, current position, and intent for all aircraft being handled. The automation also
identifies potential gaps in the arrival stream to handle aircraft being vectored that are not capable of
TBO operations. Best-equipped aircraft get the benefits of TBO and less equipped aircraft must accept
gaps in the arrival streams for high-density airports and metroplex terminal operations. Such gaps are
allocated in planning stages and adjusted to account for uncertainty. The automation injects new gaps
when needed and, to the extent practical, may delay non-equipped aircraft for which the gap is being
created.
Arrival/approach and landing TBO automation uses a combination of published arrival paths that are
connected to approaches, metering fixes, dynamic merge points, and variable descent points at TOD to
set the landing sequence and merge aircraft. Some aircraft are capable of doing their own merge and
many aircraft are capable of sustaining spacing through the use of ADS-B and cockpit display of traffic
information.
The arrival/approach and landing TBO automation also has conformance monitoring that relies on the
same parameters as used in climb, but with different, lower acceptable variability. To help manage the
variability, the arrival/approach and landing TBO automation uses learning capabilities from the
tracking and intent of previous flights, then leverages surveillance information to refine winds and
compression on arrival. By using surveillance and knowledge of aircraft performance, winds can be
estimated and corrections applied. In addition, using archived same day and same hour flight path
information, algorithms can apply corrections in near-real time to refine to seconds of performance.
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This is a rich area of research to identify the timing spread (+/-) for TOD and various other merge or
metering points along the path from cruise to touchdown.
Joint Planning and Development Office
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