14 CFR § 135.611

If a certificate holder is authorized to conduct helicopter IFR operations, the Administrator may authorize the certificate holder to conduct IFR helicopter air ambulance operations at airports with an instrument approach procedure and at which a weather report is not available from the U.S. National Weather Service (NWS), a source approved by the NWS, or a source approved by the FAA, subject to the following limitations:

The certificate holder must obtain a weather report from a weather reporting facility operated by the NWS, a source approved by the NWS, or a source approved by the FAA, that is located within 15 nautical miles of the airport. If a weather report is not available, the certificate holder may obtain weather reports, forecasts, or any combination of them from the NWS, a source approved by the NWS, or a source approved by the FAA, for information regarding the weather observed in the vicinity of the airport;

Flight planning for IFR flights conducted under this paragraph must include selection of an alternate airport that meets the requirements of §§ 135.221 and 135.223;

In Class G airspace, IFR departures with visual transitions are authorized only after the pilot in command determines that the weather conditions at the departure point are at or above takeoff minimums depicted in a published departure procedure or VFR minimum ceilings and visibilities in accordance with § 135.609.

All approaches must be conducted at Category A approach speeds as established in part 97 or those required for the type of approach being used.

Each helicopter air ambulance operated under this section must be equipped with functioning severe weather detection equipment, unless the pilot in command reasonably determines severe weather will not be encountered at the destination, the alternate destination, or along the route of flight.

Pilots conducting operations pursuant to this section may use the weather information obtained in paragraph (a) to satisfy the weather report and forecast requirements of § 135.213 and § 135.225(a).

After completing a landing at the airport at which a weather report is not available, the pilot in command is authorized to determine if the weather meets the takeoff requirements of part 97 of this chapter or the certificate holder's operations specification, as applicable.