Q-ROUTES
Naturally, the routes between some points are very
popular, so these paths are given route designators and
published on charts. The U.S. and Canada use "Q" as
a designator for RNAV routes. Q-Routes 1 through
499 are allocated to the U.S., while Canada is allocated
Q-Routes numbered from 500 through 999. The
first Q-Routes were published in 2003. One benefit of
this system is that aircraft with RNAV or RNP capability
can fly safely along closely spaced parallel
flight paths on high-density routes, which eases airspace
congestion. While the initial overall HAR
implementation will be at FL390 and above, some of
the features may be used at lower altitudes, and some
Q-Routes may be used as low as FL180. A Q-Route is
shown in figure 3-40.
![](images/chapter_3_36.jpg)
NON-RESTRICTIVE ROUTING HAR also includes provisions for pilots to choose their
own routes, unconstrained by either conventional airways
or Q-Routes. This non-restrictive routing (NRR)
allows pilots of RNAV-equipped aircraft to plan the
most advantageous route for the flight. There are two
ways to designate an NRR route on your flight plan.
One method, point-to-point (PTP), uses the traditional
fixes in the aircraft equipment database and is shown
by placing “PTP” in the first part of the “Remarks”
block of the flight plan. For
aircraft that have the additional
waypoints of the
Navigation Reference System
(NRS) in their databases,
“HAR” is placed in the first
part of the “Remarks” block.
NAVIGATION REFERENCE SYSTEM
The NRS is a grid of waypoints
overlying the U.S. that
will be the basis for flight plan
filing and operations in the
redesigned high altitude environment.
It will provide
increased flexibility to aircraft
operators and controllers. The
NRS supports flight planning
in a NRR environment and
provides ATC with the ability
to more efficiently manage
tactical route changes for aircraft
separation, traffic flow
management, and weather
avoidance. It provides navigation
reference waypoints that
pilots can use in requesting
route deviations around
weather areas, which will
improve common understand understanding
between pilots and ATC of the desired flight path.
The NRS will initially include waypoints every 30 minutes
of latitude and every two degrees of longitude. In its
final version, the NRS waypoints will have a grid resolution
of 1-degree longitude by 10 minutes of latitude. As
database capabilities for the preponderance of aircraft
operating in the high altitude airspace environment
becomes adequate to support more dense NRS resolution,
additional NRS waypoints will be established.
T-ROUTES
T-Routes are being created for those who operate at
lower altitudes. T-Routes have characteristics that are
similar to Q-Routes, but they are depicted on low altitude
en route charts and are intended for flights below
FL180. The first T-Routes are being pioneered in
Alaska.
IFR TRANSITION ROUTES
In order to expedite the handling of IFR overflight
traffic through Charlotte Approach Control Airspace,
several RNAV routes are published in the
Airport/Facility Directory and available for you when
filing your flight plan. Any RNAV capable aircraft filing
flight plan equipment codes of /E, /F, or /G may
file for these routes. Other aircraft may request vectors
along these routes but should only expect vector routes as workload permits. Altitudes are assigned by ATC
based upon traffic. [Figure 3-41]
![](images/chapter_3_38_1.jpg)
IFR transition routes through Class B airspace for general
aviation aircraft en route to distant destinations are
highly desirable. Since general aviation aircraft cruise
at altitudes below the ceiling of most Class B airspace
areas, access to that airspace for en route transition
reduces cost and time, and is helpful to pilots in their
flight planning. Establishing RNAV fixes could facilitate
the implementation of IFR transition routes,
although every effort should be made to design routes
that can be flown with RNAV or VOR equipment. IFR
transition routes are beneficial even if access is not
available at certain times because of arriving or
departing traffic saturation at
the primary airport. For these
locations, information can be
published to advise pilots when
IFR transition access is not
available. |