Air Traffic Management Concept Baseline Definition - The Boeing ...

function of all the ICPs of elements between the users (i.e., communications elements
between a pilot and a controller). Once ICP T is determined, it can be compared against a
specific RCP to determine if the RCP is met.
Determination of ICP T is part of the process of gaining operational approval for the given
RCP airspace or operation. ICP is inherently tied to one or more specific technologies. It
is the term used to describe the performance of the particular communication path as
certified by the cognizant authority. ICP can be associated with a given aircraft because it
is strongly influenced by the aircraft’s equipage and the communication support
arrangements that have been made for it.
5.1.2.3 Actual Communication Performance
Actual communication performance (ACP) is an observation of the dynamic operational
communication capability of the same communication elements as was used for the
determination of ICP. ACP is expressed in the same terms and parameters as are RCP and
ICP, but at a given instant may differ from the ICP of a particular path. ACP can be
determined by monitoring the communication path or by monitoring the current condition
of the elements of the path. It is recognized that various cognizant authorities may wish to
specify the necessary reactions of the airspace manager and flight crew when ACP differs
from ICP.
5.1.3 Navigation Performance
Airplane navigation requirements for each phase of flight are a function of airplane
separation requirements. The separation of aircraft and obstacles also provides
requirements especially in the approach/landing phase. A high degree of confidence in the
aircraft staying within a specified volume of airspace is needed to establish separation
standards. The dimensions of this volume are based on the probability of the aircraft
navigation system performance not exceeding a specified error. However, airplane
separation criteria established by the FAA also account for the availability and limitations
of communications, and surveillance services, as well as operational factors (e.g., the
crew/autopilot’s use of the navigation information to control the airplane position) in
addition to navigation requirements.
The increased equipment accuracy and world wide coverage of new systems based on
Global Positioning System (GPS) navigation will greatly improve operations because of
the performance limitations of ground aids. This is achieved in large part by providing
increased integrity monitoring and more reliability. As navigation evolves to satellite based
aids, consideration of additional failure modes will have to be considered. These and
potentially more sophisticated crew alerting schemes will keep driving new requirements
as applications evolve. Cost considerations may become driving factors, but minimizing
the impact on crew interfaces as a fundamental design philosophy will help as will the
potential use of navigation technology developed for the mass market.
RTCA’s document DO-236, “Minimum Aviation System Performance Standards:
Required Navigation Performance for Area Navigation” (RTCA, 1997) establishes the
requirements for the airborne navigation component of the CNS/ATM operating
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