21.03.2013 Views

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

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

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

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

<strong>II</strong>I-3-6-6 Procedures — <strong>Aircraft</strong> <strong>Operations</strong> — <strong>Volume</strong> <strong>II</strong><br />

23/11/06<br />

6.4.2 Origin<br />

The precision segment starts at the final approach point, that is the intersection <strong>of</strong> the nominal glide path <strong>and</strong> the<br />

minimum altitude specified for the preceding segment. The FAP should not normally be located more than 18.5 km<br />

(10.0 NM) before threshold, unless adequate glide path guidance beyond the minimum specified in Annex 10 is<br />

provided.<br />

6.4.3 Glide path verification check<br />

A fix at the FAP is necessary so as to permit comparison between the indicated glide path <strong>and</strong> the aircraft altimeter<br />

information.<br />

6.4.4 Descent fix<br />

A descent fix shall be located to start the final approach segment <strong>and</strong> it becomes the final approach point linking the<br />

MOC in the preceding segment smoothly with the precision surfaces. The descent fix should not normally be located<br />

more than 18.5 km (10.0 NM) before threshold, unless adequate glide path guidance beyond the minimum specified in<br />

Annex 10 is provided. The tolerance <strong>of</strong> the descent fix does not need to be considered due to accuracy.<br />

Note.— Guidance material for determining the distance to the descent fix from the l<strong>and</strong>ing threshold is contained in<br />

Part <strong>II</strong>, Section 1, Chapter 1, Appendix C.<br />

6.4.4.1 The provisions <strong>of</strong> Part I, Section 2, Chapter 2, 2.7.4 which allow obstacles close to the fix to be ignored,<br />

apply in the area below the 15 per cent gradient within the precision surfaces.<br />

6.4.5 Missed approach<br />

The missed approach shall be initiated no lower than the intersection <strong>of</strong> the nominal glide path with the decision<br />

altitude/height (DA/H). The DA/H is set at or above the OCA/H, which is determined as specified in 6.4.7 to 6.4.9 <strong>and</strong><br />

6.5.<br />

6.4.6 Termination<br />

The precision segment normally terminates at the point where the final phase <strong>of</strong> the missed approach commences (see<br />

Part I, Section 4, Chapter 6, 6.2.3, “Final phase”) or where the missed approach climb surface Z starting 900 m past<br />

threshold reaches a height <strong>of</strong> 300 m (1 000 ft) above threshold, whichever is lower.<br />

6.4.7 Obstacle clearance <strong>of</strong> the precision segment using basic<br />

ILS surfaces for GBAS operations<br />

6.4.7.1 General. The area required for the precision segment is bounded overall by the basic ILS surfaces defined<br />

in 6.4.7.2. In st<strong>and</strong>ard conditions there is no restriction on objects beneath these surfaces (see 6.1.3, “St<strong>and</strong>ard<br />

Conditions”). Objects or portions <strong>of</strong> objects that extend above these surfaces must be either:<br />

a) minimum mass <strong>and</strong> frangible; or<br />

b) taken into account in the calculation <strong>of</strong> the OCA/H.

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!