Author Topic: What is a CAT2 Landing  (Read 29064 times)

Offline bogman

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What is a CAT2 Landing
« on: September 22, 2008, 09:42:01 AM »
I was listening to my local ATC the other day and the pilots requested an updated weather forecast.The controller gave it to him,can't remember what it was but there was mist,fog and broken cloud mentioned.

When the pilot heard this he straight away requested a CAT 2 landing,hence my question what is a CAT 2 landing.


Also is there a difference to a CAT 1 landing and is there a higher CAT landing or is CAT 2 the highest.



Offline MathFox

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Re: What is a CAT2 Landing
« Reply #1 on: September 22, 2008, 09:51:26 AM »
There also is CAT 3, subdivided in 3A, 3B and 3C.
See the excellent description on Wikipedia: http://en.wikipedia.org/wiki/Instrument_landing#ILS_categories

Offline cessna157

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Re: What is a CAT2 Landing
« Reply #2 on: September 22, 2008, 02:58:06 PM »
The wiki pretty much sums up all three categories.  You'll probably never see someone fly a Cat IIIc landing, as once you're on the ground, you're completely screwed because you cannot see the taxiway to turn on to.

Offline MathFox

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Re: What is a CAT2 Landing
« Reply #3 on: September 22, 2008, 05:24:31 PM »
I think one could get a plane in when there's about 20 meters of visibility... Have a follow-me car guide the plane off the runway to the gate.
The car driver is low enough to see the centreline on the taxiway... the lights on the car are visible enough for the taxiing pilot. If that doesn't work one can tow in the plane...

(I have sailed in 20 meter visibility... with a boat that's 20 meter long. There were people at the bow of the boat shouting steering instructions to the stern. It is weird to steer a boat when you can not see the bow, or anything in front of the boat. It works thanks to good teamwork.)

Offline bogman

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Re: What is a CAT2 Landing
« Reply #4 on: September 24, 2008, 02:34:27 PM »
Thanks guys that explains everything.... :-D :-D :-D :-D :-D

drfinal

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Re: What is a CAT2 Landing
« Reply #5 on: September 24, 2008, 03:56:06 PM »
We did a Cat3 landing in the old TWA sim at JFK years ago. We didn't see a thing until the 'plane' touched down and we saw the centerline.

A thing of beauty.

Offline Seaton Tower

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Re: What is a CAT2 Landing
« Reply #6 on: November 07, 2008, 12:21:50 PM »
The wiki pretty much sums up all three categories.  You'll probably never see someone fly a Cat IIIc landing, as once you're on the ground, you're completely screwed because you cannot see the taxiway to turn on to.

I was under the impression that for CATIIIC the minimum requirement was for the aircraft to be able to taxi to the gate completely automated? And that the main reason for them not being used much is that there are no airports with the capability to allow this (I believe some sort of sub-taxiway guidance system is required)
« Last Edit: November 07, 2008, 12:23:32 PM by Seaton Tower »

Offline cessna157

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Re: What is a CAT2 Landing
« Reply #7 on: November 07, 2008, 12:35:07 PM »
I am not aware of any aircraft type that can steer itself on the ground.  I am also not aware of any type of system you speak of with taxiway guidance.  There are too many obstacles for an aircraft to avoid while on the groud, especially in the ramp area.  No aircraft would be able to do this.

Offline Seaton Tower

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Re: What is a CAT2 Landing
« Reply #8 on: November 07, 2008, 01:03:10 PM »
I am not aware of any aircraft type that can steer itself on the ground. 

Neither am I. Which is another reason why CAT IIIC approaches are never seen. But I am sure that the minimum requirement for CAT IIIC is full autoland, auto-rollout and auto-taxi from runway to terminal.

Quote from: Avionics Magazine
While today’s autoland systems could perform CAT IIIc operations, there are currently no certified surface guidance systems that would then take the aircraft safely and accurately off the runway and guide it to the terminal.
« Last Edit: November 07, 2008, 01:11:45 PM by Seaton Tower »

Offline cessna157

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Re: What is a CAT2 Landing
« Reply #9 on: November 07, 2008, 02:04:25 PM »
But I am sure that the minimum requirement for CAT IIIC is full autoland, auto-rollout and auto-taxi from runway to terminal.


Which reg is that?   I cannot find it in either 121 or 91.  I was aware that IIIc is autoland and rollout, I was not aware taxi guidance was required too.  Which raises my next question:  Why would they certify approach systems and procedures to IIIc, but then have no system to guide the aircraft to the gate?  Thats why I don't think there is any requirement for taxi-in.  Most airlines and operators do not permit it in their own company specs as the taxi in would be very dangerous.  But I do not agree that it is a legality thing.

Offline Casper87

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Re: What is a CAT2 Landing
« Reply #10 on: November 08, 2008, 07:14:41 AM »
There is no "minimum taxiway" requirement for CATIIIC approaches. Just the approach minima.

Offline Seaton Tower

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Re: What is a CAT2 Landing
« Reply #11 on: November 08, 2008, 11:00:03 AM »
I think you'll find there is. Unfortunately the only place I can find where it is detailed is in JAR-OPS publications which I have no access to. What would be the point in having a no-minima RVR approach when the pilot cannot then taxi to the gate because he can't see the taxiway? CAT IIIC requires Auto-Land, Auto-Rollout to safe taxi speed and taxi guidance from runway to gate.

Offline glencar

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Re: What is a CAT2 Landing
« Reply #12 on: November 08, 2008, 11:09:49 AM »
From the Wiki Wiki link above, this might help youse: "Category III C - A precision instrument approach and landing with no decision height and no runway visual range limitations. A Category III C system is capable of using an aircraft's autopilot to land the aircraft and can also provide guidance along the runway surface."

Offline FlySafe

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Re: What is a CAT2 Landing
« Reply #13 on: November 13, 2008, 07:57:44 AM »
CAT II, IIIA, IIIB and IIIC requires special aircrew and aircraft certification (many times the aircraft is capable but the crew isn't).  Visibility triggers a CAT II-III checklist.  CAT II and any III operation cannot be conducted until all of the checklists are complete.  This involves, uninterrupted power (generators on) to the approach lights, ILS and runway lights (including centerline and touchdown), visual inspection of all lighting componenets and required notifications.

CAT IIIc is 100% auto-land AND  specified airport improvements are required to be designated IIIc.  One of the requirements are taxiway lead-in/center-line lead-in lights. 

When an airport is in this condition SMGCS (Surface Movement Guidance System) is also in effect.  That is where the airport is required to have a follow-me vehicle available upon request.