Boroda
5th Feb 2010, 14:50
Such landings are approved according to Limitations under condition that the airline has checked the ILS beam quality and the effect of terrain profile before the RW.
Here is the question. How does your airline follow this requirement practically? And does your company try to meet this? If not what advice could you give me to avoid this limitation? Is such way out possile as to land on CAT 2, 3 installations only and inform ATC about autoland intentions before, so no need for statement above.
I'd love to hear an answer on this. The subject has come up several times here but never with a satisfactory conclusion. Maybe a fresh look.........
Here's the FCOM limitation:
The automatic landing system's performance has been demonstrated on runways equipped with CAT II or CAT III ILS approaches. However, automatic landing in CAT I or better weather conditions is possible on CAT I ground installations or on CAT II/III ground installations when ILS sensitive areas are not protected, if the following precautions are taken:
- The airline has checked that the ILS beam quality, and the effect of terrain profile before the runway have no adverse effect on AP/FD guidance. In particular, the effect of terrain discontinuities within 300 meters before runway threshold must be evaluated.
Using the above, you simply restrict the fields you want to do this at based on the appropriate threshold criteria (available from Airbus)
- The crew is aware that LOC or GS beam fluctuations, independent of the aircraft systems, may occur and the PF is prepared to immediately disconnect the AP and take appropriate action, should unsatisfactory guidance occur.
You can't guarantee beam integrity from one approach to the next. There will always be the chance of adverse fluctuations happening at critical moments without time to recover
- At least CAT2 capability is displayed on the FMA, and CAT II/CAT III procedures are used.
- Visual references are obtained at an altitude appropriate to the performed CAT I approach, otherwise go-around is initiated.