Originally Posted by
WhiteKnight
Maybe I am just pedantic. According my company procedure I cannot fly a CAT 2/3 approach, unless low visibility procedures are in force. ( I assume it’s not only signal protection but also other precaution measures)
As far as I understand in JFK they only put them in force below RVR 1200. Above 1200 RVR they somehow protect the signal. But what’s the difference? Why don’t they apply low visibility procedures as soon as the weather gets below CAT 1 minima?
To the best of my knowledge as a line Pilot:
Any time ceiling and visibility are below 800' or 2 miles, ATC has procedures to protect the signal accuracy of the ILS. Those include holding short further away from the RWY for departing/taxiing aircraft, vehicle traffic in the antenna area, and so on. So any time you have to do an ILS approach because weather doesn't allow for a visual, you know the signal is protected, at least at a towered airport.
The FAA has decided that for ground movement RVR of 1200 and above does not require LVP, as, in their opinion, there is no problem maneuvering around the airport at low speed in those conditions. For operations below RVR 1200, there will be different taxi diagrams, and for operations below RVR 600 there would be another set of diagrams, but not all airports will have those.
If you work for a US company your OpSpecs will authorize and explain how to comply with these rules.
If you work for a foreign company, and fly into the US, you should have a chapter somewhere in your manual explaining the difference between your local rules and the US, and how to handle this situation.
If there is nothing in your manual, it sounds like you would be unable to accept an approach into JFK with a visibility between RVR 1200 and RVR 1800, and that doesn't really make sense.
https://www.faa.gov/documentLibrary/...er_800094A.pdf
ORDER 8000.94A
4. Scope. This order establishes an FAA inter-service agreement that provides for consistent low-visibility (less than RVR 1200) airport operations; establishes requirements for uniform lowvisibility airport equipment and enhancements; and implements uniform air traffic control (ATC) and airport operator practices and expectations. Note: For the purposes of this order, LVO means those airport operations conducted at visibilities of less than RVR 1200.
https://www.faa.gov/documentLibrary/...9-22_FINAL.pdf
FAA Order JO 7110.65, Air Traffic Control
3−7−5. PRECISION APPROACH CRITICAL AREA a. ILS critical area dimensions are described in FAA Order 6750.16, Siting Criteria for Instrument Landing Systems. Aircraft and vehicle access to the ILS critical area must be controlled to ensure the integrity of ILS course signals whenever conditions are less than reported ceiling 800 feet or visibility less than 2 miles. Do not authorize vehicles/aircraft to operate in or over the critical area, except as specified in subparagraph a1, whenever an arriving aircraft is inside the ILS outer marker (OM) or the fix used in lieu of the OM unless the arriving aircraft has reported the runway in sight or is circling to land on another runway.