JohnBurke

You need to consider the regulation in context, and as applicable to the operation (what you're doing). There is no conflict.

https://www.ecfr.gov/current/title-1...-121/subpart-U

With 14 CFR 121.651(b)(2), you are specifically referencing a visibiity requirement required to fly beyond the final approach fix.

With 14 CFR 121.655, the latest weather becomes controlling. One may have departed with a better forecast, but the latest report is controlling, and if a report exists for a specific runway, then that, too, is controlling for that runway.

Adequate forecast weather must exist to dispatch the aircraft. Upon arrival adequate weather must exist in the latest weather report. Seems obvious: it's codified in the regulation. Where you appear to see the perceived conflict is a regulation which stipulates that the lastest weather report must show adequate weather above mininums (121.655 encompasses both ceiling and visibility), and a regulation which states one can't fly past the final approach fix unless the visibility. is good enough. Both can be correct; both are correct.

Elsewhere, the FAA has also recognized both ceiling and visibility as pertinent. in a FAA chief legal counsel letter of interpretation to Capital Cargo, the Administrator answered a question about a dispatch release for IFR or over the top operations. The administrator stated:

https://www.faa.gov/sites/faa.gov/fi...rpretation.pdf

That interpretation is answer a question about dispatch and release under IFR or VFR over the top, and points to 61.613, but the salent reference is the FAA's position on the relevancy of both ceiling and visibility.

121.655 is not irrelevant, nor redundant, and is not unnecessary. It should not be overlooked in both the key points in the paragraph: the latest weather (both ceiling and visibility) is what controls for takeoff or landing, and specific latest weather for a given runway, is controlling.

Don't overlook the fact that many operators have authorizations for lower minimums, and many approaches don't have a weather minimum for ceiling. Some do. Where a ceiling is prescribed, it must be adhered, just as visibility. Where only visibility is prescribed as a minimum, that must be adhered. On a typical category 1 approach, for example, a minimum visibility exists for the approach, but the altitude value is a minimum altitude to which one can descend and make a visibility decision. Other procedures may specify both ceiling and visibility, and one would be defenseless if attempting to fly an approach with 900' MDA when the latest reported ceilign is at 200'. Some takeoff procedures or departures specify a minimum visibility and ceiling for adequate visual reference to obstacles.

There is no one-stop-shop for the weather requirements. Applicable requirements include various sections of the regulation, the instrument procedures, operations specifications, and the nation-state in which one is operating, all come to bear; in nearly all cases, the most restrictive requirement applicable to that operator in that aircraft in that location, with that pilot or crew, determines what minima are required. 121.655 simply states that the current weather is the controlling weather for takeoff and landing; not the forecast, not the "tempo" in the forecast, not a recent PIREP. Current reported weather, which includes a tower report. Specific requirements exist to begin the approach, to fly beyond the final approach fix, and to go below minimums upon arrival at minimums, etc.

121.651(b)(2) is a narrow application. It covers required weather to go beyond the FAF. 121.655 has a broader application. One does not replace the other, nor take away from it.

No: 121.655 specifically states that it is applicable to VFR AND IFR takeoffs and landings, AND for instrument approaches:

https://www.ecfr.gov/current/title-14/section-121.655