CAT I approach with conditions change

[GT3]

If you are approaching an airfield that at the time of commencing the approach is in CAT I conditions, you have also briefed as such, and the weather whilst you are on final changes to just below CAT I conditions into CAT III LVPs. What would you expect in this scenario?

Firstly as you are flying CAT I do you expect protection of the localiser above what CAT I (non-LVP) conditions require? Also if the weather on the approach that you are flying in permits a CAT I landing would you be happy to land even if the reported wx has just changed to CAT III conditions?

[Miles Magister]

If it deteriorates before you reach the FAF then you must abandon the approach. If you have passed the FAF then continue to DA and make the appropriate decision based on the visual references you achieve.

MM

[brain fade]

After 4 miles or OM etc, RVR is advisory. So have a look!

[Musket90]

Regarding protection of Localiser when conditions change from Cat I to Cat III, there should be low vis procedures in place at airports when conditions are forecast to drop below Cat I. If you have started the approach in Cat I and it deteriorates below this then it is very likely Localiser safeguards are already in place and ATC should inform you that low vis procedures are in force. If the Localiser is not safeguarded for Cat II/III then ATC should inform you.

[captjns]

If, after passing the outer marker or equivalent position, the reported RVR/visibility falls below the applicable minimum, the pilot-in-command may continue the approach to DA or MDA and the landing may be completed provided that the required visual reference is established.

[drag required]

Approach Ban - All Aircraft
8.1 The requirements for the commencement and continuation of an approach are defined in Articles 47, 48 and 49 of the Air
Navigation Order 2005.
8.2 An aircraft may commence an instrument approach regardless of the reported RVR/Visibility but the approach shall not be
continued below 1000 ft above the aerodrome if the relevant RVR/Visibility for that runway is at the time less than the specified minimum
for landing.
8.3 Where RVR is not available, RVR values may be derived by converting the reported visibility in accordance with paragraph 7.
8.4 If, after passing 1000 ft in accordance with paragraph 8.2, the reported RVR/Visibility falls below the applicable minimum, the
approach may be continued to DA/H or MDA/H.
8.5 The approach may be continued below DA/H or MDA/H and the landing may be completed provided that the required visual
reference is established at the DA/H or MDA/H and is maintained.

[GT3]

Thanks for the replies. If we (LHR) are in CAT I conditioins the runways will be safeguarded if LVPs are forecast to happen or the weather is near to the limits. However for example as cloud base and vis are rounded to 100ft or 100m increments. If the vis fell below 700m to the extent that it is reported as 600m but is greater than that whilst officially in LVPs the actual weather may not warrant LVPs.

Would you expect to be sent around as the LSA will not be clear or are you happy to continue the approach and make your own descision on the CAT I levels you briefed for?

[despegue]

You can legally continue the whole approach until DA. Just do not ask for an RVR over the FAF/OM/1000' whichever appropriate for the approach in question. Before these, you can continue, after these also until minimums.
There is really no such thing as an "approach ban"!

[chevvron]

At my airport, we only have Cat 1, but safeguarding commences at RVR 1500m/ceiling 200ft or less. Maybe airports with Cat 11/111 capability should do likewise in order to reassure you guys that it's safe.

[SpringbokDreamer]

despegue...:=

You're talking absolute Twoddle!!! Read Drag required post... and learn something...PLEASE!

Basics really, I hope your defence is that you don't have your IR yet?

Regards Dreamer