Aircraft Operations. Volume II - Construction of Visual and Instrument ...

Part II — Section 1, Chapter 3 II-1-3-5
distance not exceeding 41.7 km (22.5 NM) from the azimuth antenna. When radar is used to provide track guidance to
the IF, the area shall be in accordance with 6.2, “Initial approach segment” (Section 2, Chapter 6, “SRE”).
3.3 INTERMEDIATE APPROACH SEGMENT
3.3.1 General
3.3.1.1 The intermediate approach segment for MLS differs from the general criteria in that:
a) the alignment coincides with the MLS azimuth specified for final approach track;
b) the length may be reduced; and
c) in certain cases the secondary areas may be eliminated.
3.3.1.2 The primary and secondary areas at the FAP are defined in terms of the ILS surfaces. Consequently, the
general criteria in Part I, Section 4, Chapter 4, “Intermediate approach segment” are applied except as modified or
amplified in the paragraphs below with regards to alignment, area length and width, and for obstacle clearance. For
RNAV initial approach segments, the criteria in the applicable RNAV chapters apply.
3.3.2 Intermediate approach segment alignment
The intermediate approach segment of an MLS procedure shall be aligned with the MLS azimuth specified for the final
approach track.
3.3.3 Intermediate approach segment length
3.3.3.1 The optimum length of the intermediate approach segment is 9 km (5 NM). This segment shall allow
interception with the final approach track and with the glide path (MLS elevation angle).
3.3.3.2 Segment length should be sufficient to permit the aircraft to stabilize and establish its course on the final
approach track prior to intercepting the glide path (MLS elevation angle), taking into consideration the angle of
interception of the final approach track.
3.3.3.3 Minimum values for distance between interception of final approach track and interception of glide path
are specified in Table II-1-3-1; however, these minimum values should only be used if usable airspace is restricted. The
maximum length of the segment is governed by the requirement that it be located wholly within the operational
coverage region of the approach azimuth, and normally at a distance not exceeding 37 km (20 NM) from the runway
threshold.
3.3.4 Intermediate approach segment area width
3.3.4.1 The total width at the beginning of the intermediate approach segment is defined by the final total width of
the initial approach segment. It tapers uniformly to match the horizontal distance between the OAS X surfaces at the
FAP (see 3.4.8.3, “Definition of obstacle assessment surfaces (OAS)”).
23/11/06