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cork diversion

Posted: Wed Jan 04, 2006 4:51 pm
by Dutch Roll
ha amazed to read in the evening echo that shannon was fog bound yestrerday so an aircraft diverted to cork for once,it was none other than a USAF gulfstream 4,the antiwar idiots are causing a stir!!

Posted: Wed Jan 04, 2006 5:53 pm
by VNAV PTH
A diversion due to fog? Hardly a newsworthy event. Was the headline "400 in near death jet disaster as Boeing 320 pilot flies blind"?

Posted: Wed Jan 04, 2006 6:35 pm
by Dutch Roll
was more like ''US military aircraft enroute to bomb iraq also carrying terrorist suspects'' lands in cork.

Posted: Thu Jan 05, 2006 10:29 am
by Rallye EIBFP
Watch out Cork- the guys with the Anti War Banners will arrive soon!

that pilot said he could not accept a CATII approach or something....all other flights were grand operating CATII. Vis was down to 100m!

Posted: Thu Jan 05, 2006 12:59 pm
by VNAV PTH
Rallye EI-BFP wrote:...that pilot said he could not accept a CATII approach or something....all other flights were grand operating CATII. Vis was down to 100m!



Met vis isn't the critcal factor, it's the RVR.

Posted: Thu Jan 05, 2006 2:20 pm
by Dutch Roll
yip CAT2 is min RVR of 350M,i know some airlines wont shoot a CAT2 approach unless its 400M RVR,

The anti-war banners were already out i think!!!

Posted: Thu Jan 05, 2006 2:39 pm
by Rallye EIBFP
Ryanair flew in grand in the 100m visibility (and did not request CAT2, alas!) Aer Lingus wanted to fly a few orbits before landing to see if it cleared etc.......A World MD11 was saying if he could not make it in two approaches he would divert...but his alternate was Heathrow!!

Posted: Thu Jan 05, 2006 3:39 pm
by VNAV PTH
Rallye EI-BFP wrote:Ryanair flew in grand in the 100m visibility (and did not request CAT2, alas!)


Visibilty is the greater of:

a) the greatest distance at which a black object of suitable dimensions, situated near the ground, can be seen and recognised when observed against a bright background.

b) the greatest distance at which lights in the vicinity of 1000 candles can be seen and indentified against an unlit background.

RVR is:

The range over which the pilot of an aircraft on the centre line on a runway can see the runway surface markings or the lights delineating the runway or identifying its centre line.

These are ICAO definitons.


The reported values of these two can be distinctly different. However, TDZ RVR is the measurement used for approach minimums. Usually, but not always, minimums are CAT I...550m, CAT II...300m, CAT IIIA...200m. Company procedures can impose higher, but not lower values. If no RVR is available, met vis values can be used, but have a multiplication factor applied to them.
If an airfield is under LVP, this will be broadcast to aircraft on the ATIS, or informed by ATC. Therefore there is no need, under these circumstances, for an aircraft to explicitaly request a CAT II/III approach.

USAF diversion..

Posted: Sat Jan 07, 2006 12:12 am
by corkspotter
Just for information,

Aircraft was C-20D 163692. Have posted a photo in the photo section. Enroute Andrews to KWI.

Regards,

Paul D

Posted: Sat Jan 07, 2006 5:59 pm
by airoshane
The aircraft abuse the RVR rule. The RVR may be 300m and an ATR wants to do a Cat I approach. They usually wait a while and the RVR may jump to 600 m only for a few seconds. ATC announce the new RVR and the aircraft take a "pot shot" at it. The ATC calls out the RVR again when the aircraft are on finals but if it is back below the limit the aircraft still go ahead and try the approach.

Aer Arann are brilliant at taking pot shots at cork!

Posted: Sat Jan 07, 2006 6:14 pm
by VNAV PTH
airoshane wrote:The aircraft abuse the RVR rule. The RVR may be 300m and an ATR wants to do a Cat I approach. They usually wait a while and the RVR may jump to 600 m only for a few seconds. ATC announce the new RVR and the aircraft take a "pot shot" at it. The ATC calls out the RVR again when the aircraft are on finals but if it is back below the limit the aircraft still go ahead and try the approach.


I can guarantee it's not a "pot-shot". You may have a good career ahead of you writing for The Sun!! :lol:


An aircraft cannot commence an approach, ie leave the IAF unless the current RVR is above the minimum required.
If after leaving the IAF, the reported RVR falls below the minimum required, the approach can be continued as far as the OM/4DME fix/FAF or a point designated as such. On reaching this point, the minimum RVR must be above limits or a missed approach is required.
If all is above limits, but after passing the OM/4DME/FAF point, the RVR falls below minimum, the approach may be continued to DH and a landing made if the required minimum visual reference is attained.

Of course, this is a generic procedure, but most airlines will have SOP`s based around this.

Posted: Mon Jan 09, 2006 1:16 pm
by Dutch Roll
[quote="VNAV PTH]
I can guarantee it's not a "pot-shot". You may have a good career ahead of you writing for The Sun!! :lol:[/quote]

excellent