7754 Vol 1 Flyleaf - ICAO Public Maps

II-4 EUR BASIC ANP
30. Aircraft using ATS routes will, to the extent
possible, be operated along the centre lines of the routes
and will, in any case, remain within the specified lateral
31. Aircraft are capable of navigating satisfactorily
under the following conditions:
a) that normal navigational guidance along a given ATS
route is considered to exist if the designated operational
coverage of a navigation aid is specified up to at least
the halfway point between it and the next aid on the
route in question, plus a specified overlap (see also
criterion No. 6 in Attachment J to Part IV — CNS of
the EUR FASID);
b) that significant points, either en route or within TMAs,
are established with reference to:
1) the radial of a VOR used for track guidance and its
intersection with a radial of another VOR, provided
the angle of intersection of the two radials is not less
than 45� and not more than 135�;
2) a radial of a VOR, combined with a specified DME
indication from its co-located DME or from the
co-located DME of the next VOR intended to be
used for track guidance, provided the point is
located within the designated operational range of
that DME.
Note.— Other arrangements may be made subject
to agreement between States and operators concerned.
32. For operation on RNAV routes where specified
limits of such routes.
[Annex 6, Parts I and II, Chapter 7; Annex 2, 3.6.2.1.1]
values of navigation accuracy are prescribed by regional air
navigation agreement, aircraft will be capable of meeting
these values. In the EUR region, two levels of navigational
accuracy have been established. For en-route purposes the
values are as follows:
a) basic RNAV, having a navigation performance equal to
or better than a track-keeping accuracy of ± 9.3 km
(± 5 NM) for 95 per cent of the flight time of all aircraft
using basic RNAV equipment. This level is similar to
that currently achieved by aircraft without RNAV
capability operating on existing routes defined by VOR
or VOR/DME, where VORs are less than 185 km (100
NM) apart;
b) precision RNAV, having a navigation performance
equal to or better than a track-keeping accuracy of 0.93
km (0.5 NM) standard deviation. This level of accuracy
is currently achieved by aircraft with a capability
similar or superior to continuous automatic dual DME
position fixing and updating.
Note.— While this accuracy level is still under
evaluation, it is expected to be compatible with total
route widths of less than 11 km (6 NM). Trials are
planned to validate the basic criteria and to develop the
precision criteria into a recommended route width.
These criteria will then be expressed in terms similar to
those used for basic RNAV.