Confused: "CAT 2" and "LVP"

LVP is my experience is used in relation to ground movements. It can often mean the tower can’t see the full airfield. It can require reporting when you get to certain holds and limit taxiing multiple aircraft at once. My understanding of CAT II and CAT III is that they relate to the cloud and visibility minima.

Isn’t “CAT” only a category for landings? I thought as a private pilot with IR you’re not allowed to go lower than 200 ft AGL, and that’s CAT 1. And wasn’t it 550 m for take-off?

LVP are low visibility procedures for ground traffic. Some airports (wrongly) call them CAT II or III conditions, because they are often implemented and certain stages correspond to the conditions for CAT II or III approaches.

Low visibility procedures are usually in force when the airport tower can not see the traffic it is controlling other than by the use of ground radar (where available) or procedural control (position reports of the airplanes). Additional restrictions come in place when CAT II or III ILS operations are conducted as this means that the holding points for the runways change to the CAT II/III holdings as well as increased separation (also on the ground for ground traffic) and some other stuff.

I can look it up once I get back home next week but that is the gist of it. LVP describe the ground procedures used in low visibility, which can but not necessarily are limited to CAT II or III ops (LVP can start with as much as 1000m visibility in some places). So the term CAT II conditions is not quite correct but it can describe additional restrictions to the basic LVP with higher visibility.

Mooney_Driver wrote:

Low visibility procedures are usually in force when the airport tower can not see the traffic it is controlling other than by the use of ground radar (where available) or procedural control (position reports of the airplanes).

No.
We activate LVP when some ceiling or visibility (or RVR as applicable) criteria are met.
At my airport, we activate LVP when the RVR is 600m (or less) or ceiling is 200 ft (or less).

Here are two counterexample :

• When we have ceiling at 190 ft and visibility more than 10 km : we are LVP although we can see everyone on the ground.
• When we have about 800 m RVR : we are not LVP and we don’t see the runways from the tower.

For the airport, it implies :

• The localizer of the opposite runway in use is shutdown (to prevent interference)
• CAT II/III runway lighting is in use.
• Two power sources are available.
• Some firecrews are ready in their firetruck (engine started).
• We activate some red stopbars to prevent runway incursion…
• The runway protected areas are bigger/larger.
• ….

For aircraft crews “LVP in force” just means you can perform CATII / CATIII or LVTO.
CATI and “regular” take-off are still possible even when LVP are in force (according to the current weather).

Your minimums for the CATII/CATIII approach should be calculated according to :

• The minimums stated on the approach chart.
• The aircraft minimums.
• The operator certification
• The crew qualification.

One important thing about LVP (or LVO, as they are also called) is that their cancellation is not automatic as the visibility improves. On my overnight stop at Charleroi EBCI last winter, the visibility dropped to CAT II levels shortly after I landed, and the airport promptly imposed the LVO; in the morning, the visibility was a lot better (see photo), but LVO remained in effect until after I departed – in particular, I was not allowed to taxi to the fuel pump but had to call a fuel truck instead (for an extra €10 or so).

But there are plenty of airports eg Oxford that have LVPs without anything other than a CAT I ILS. And there the initiation of LVP is entirely visibility related:

1. INSTRUMENTED RUNWAY VISUAL RANGE (IRVR)
An IRVR sensor is installed at Oxford Airport to facilitate the CAT I ILS. It is
positioned to the right of the runway adjacent the 19 threshold.

2. ACTIVATING OF LVPs
In deteriorating weather conditions, the DATCO will initiate LVPs. There are two
stages which may be initiated dependant on the visibility.
2.1. LVPs Stage 1
When the visibility is less than 1500m the DATCO will initiate LVP Stage 1. In this
event the DATCO shall:
a) Select all runway lighting, including the stop-bars and runway guard lights;
b) Inform Operations, RFFS and Security that LVPs have been initiated;
c) Disseminate meteorological information; and
d) Request that RFFS complete a runway and lighting inspection and display LVP
signage at all non-essential access points to the manoeuvring area (see
section 3.1.

When ATC have been informed that the above actions have been completed the
DATCO shall make an entry in the ATC Watch Log stating that Stage 1 LVPs are in
force.

2.2. LVPs Stage 2
ATC will monitor the promulgated and forecast weather. If the Met Visibility reduces
to 1000m or below, the DATCO shall, in addition to the steps in Section 2.1 above:
a) Select auxiliary power;
b) Instruct all non-essential vehicles to leave the manoeuvring area;
c) Inform all persons conducting work-in-progress on any part of the manoeuvring
area to cease immediately and vacate the manoeuvring area;
d) Suspend any routine maintenance;
e) Ensure that all activity on the manoeuvring area is brought under the specific
control of ATC;
f) Request that the RFFS make an additional inspection of any areas vacated by
work parties; and
g) Ensure that all persons and vehicles are clear of the ILS critical areas.

When the DATCO has completed all of the above and a satisfactory aerodrome
inspection report is received from RFFS, the DATCO shall make an entry in the
ATC Watch Log stating that Stage 2 LVPs are in force.

One important thing about LVP (or LVO, as they are also called)

No LVP and LVO are different things. LVO are aircraft operations in less than Cat I minima for arrivals or 400 m RVR for departures. LVP are the procedures at the airport. Usually, an operator’s LVO approval will be dependent on LVP being in place at the airport.

SPA.LVO.115 Aerodrome related requirements
(a) The operator shall not use an aerodrome for LVOs below a visibility of 800 m unless:
(1) the aerodrome has been approved for such operations by the State of the aerodrome; and
(2) low visibility procedures (LVP) have been established.
(b) If the operator selects an aerodrome where the term LVP is not used, the operator shall ensure that there are equivalent procedures that adhere to the requirements of LVP at the aerodrome. This situation shall be clearly noted in the operations manual or procedures manual including guidance to the flight crew on how to determine that the equivalent LVP are in effect