Good morning. Short answer to your options is neither.
In the real world, it depends on whether the operation is private (Part 91) or commercial (Part 121, 135, etc.). (I use private vs. commercial and the Parts involved generally; there are nuances not that would make this a 9 page answer -- not worth it. )
Part 91, you can shoot approaches to airports that are reporting weather below minimums all day long (or until you run out of gas! ). There's nothing wrong with it. There are numerous possible reasons, but I'll mention just 2 to illustrate:
1. The weather is changing very rapidly and the conditions are hovering just about at minimums, but the latest observation is just below. When you shoot the approach, you may be pleasantly surprised.
2. You actually want to see what it looks like to get down to minimums and NOT see what you need to see to continue the approach to a landing. As a formerly very active flight instructor, I used to seek out those opportunities for the benefit of my students -- it teaches a marvelous lesson.
In either case as described above, you MUST have a good Plan B (so you don't end up turning your situation into an emergency, or worse, accident), and assume going in that you're not going to be landing there, and be very pleasantly surprised if you can....
So as to avoid another 9 pages worth of response, I'll cover commercial (Part 121 Air Carrier, Part 135 Air Charter, etc.) by saying that, in general, there are regulations (either FAR or Company Operating Specifications) that don't allow (or otherwise regulate) a crew to commence an approach when the current weather observation is reporting weather below minimums.
So back to how you'd handle your aviator, based on your example....
Example: A pilot is inbound to an airport, the weather is bad the ceiling and visibility are both below the published minimums for the ILS approach. You inform the pilot of the conditions offering both a hold or diversion. After reviewing his options the pilot would still like to proceed inbound for the approach.
You do inform the pilot of the conditions, but do not automatically offer a hold or a diversion. Let the pilot fly his aircraft. The pilot in command is responsible for the flight, and must make the decisions. (Foregoing a couple of extra pages of response based on what you might actually do in the event that the pilot has declared (or you have declared for him) an emergency and you are offering assistance). I would simply do one of two things:
1. Ensure he has the current weather and continue to vector/clear him for the advertised (or requested) approach.
2. Ensure he has the current weather and ask the pilot his intentions.
Getting back to your two options, advising him landing is at his own risk is not authorized in this scenario (unless you are acting as local control and the airport is closed for the landing operation he is seeking to perform, or unless he is in a helicopter planning to land off airport, etc.). You don't need to cancel his radar services - this type of scenario is when he needs your services the most, and when he needs you to be at your best!
You simply bring him in and clear him for the approach. If you are working Local, you ensure he has the current weather (particularly if it's different than the ATIS he has acknowledged), and then clear him to land.
Baron 7556Y, Wind 030 at 6, visibility now 1/16th mile in heavy snow, Runway 5, cleared to land.
Whether he lands or not is his business, and he'll have to deal with the FAA (or the Maker) if he makes the wrong choice.....
Sorry for the long reply, and hope this helps. [Disclaimer: There are a gazillion nuances associated with what I've typed above, but my fingers hurt and you don't want to read all about those anyway, so this is pretty generic, but covers the majority of situations out there, especially for VATSIM ]
Don Desfosse, ATP, CFII, MEII
FAA Aviation Safety Counselor and FAASTeam Lead
vZBW Air Traffic Manager
