For the only published approach at your destination heliport, what are the minimum weather requirements for filing?

The minimum weather requirements for filing an IFR flight plan to a destination where the only published approach is available are typically based on the type of approach and its associated standards. In this case, the correct choice indicates that 0.5 miles visibility is required, allowing for a certain degree of flexibility with an estimated time of arrival (ETA) that is plus or minus 1 hour.

When a pilot files to an airport or heliport with a published approach, it is essential to consider the regulatory standards that dictate minimum visibility for making such a flight safe and compliant with air traffic control requirements. In this scenario, the 0.5 miles visibility permits operations under conditions that may not be ideal, but still ensure safety because of the established approach procedures.

The tolerance of an ETA within 1 hour allows pilots to adjust for en route conditions or delays while remaining within safe operating criteria. It's worth noting that the other options specify different visibility requirements which do not align with the regulations established for only published approaches at a heliport. Such alternatives reflect either higher visibility requirements or shorter ETA windows, which could exceed the regulatory minimum for this specific scenario and are therefore not appropriate.