Aviation Weather Service Program (Part Two)

1.3.1 Weather Briefings. Prior to every flight, pilots should gather all information vital to the nature of the flight. This includes a weather briefing obtained by the pilot from an approved weather source, via the Internet, and/or from an FSS specialist.

The FSS’ purpose is to serve the aviation community. Pilots should not hesitate to ask questions and discuss factors they do not fully understand. The briefing should be considered complete only when the pilot has a clear picture of what weather to expect. Pilots should also make a final weather check immediately before departure, when possible.

To provide an appropriate weather briefing, specialists need to know which of the three types of briefings is needed—standard, abbreviated, or outlook. Other necessary information includes whether the flight will be conducted with VFR or IFR, aircraft identification and type, departure point, estimated time of departure, flight altitude, route of flight, destination, and estimated time en route. If the briefing updates previously received information, the time of the last briefing is also important. This allows the briefer to provide only pertinent data.

The briefer enters this information into the FAA’s flight plan system. The briefer also notes the type of weather briefing provided. If necessary, the information can be referenced later to file or amend a flight plan. It is also used when an aircraft is overdue or is reported missing. Internet data is time-stamped and archived for 15 days. Voice recordings are retained for 45 days.

1.3.1.1 Standard Briefing. A standard briefing provides a complete weather picture and is the most detailed of all briefings. This type of briefing should be obtained prior to the departure of any flight and should be used during flight planning. A standard briefing provides the following information (if applicable to the route of flight) in sequential order:

• Adverse Conditions. This includes information about adverse conditions that may influence a decision to cancel or alter the route of flight. Adverse conditions include significant weather (e.g., thunderstorms, aircraft icing, turbulence, windshear, mountain obscuration, and areas of current and forecasted IFR conditions) and other important items, such as airport/runway closings, air traffic delays, and temporary flight restrictions (TFR).

• VFR Flight NOT RECOMMENDED (VNR). If the weather for the route of flight is below VFR minimums, or if it is doubtful the flight can be made under VFR conditions due to the forecasted weather, the briefer may state that VFR is not recommended. The pilot can then decide whether or not to continue the flight under VFR, but this advisory should be weighed carefully. This advisory is not provided via the Internet.

• Synopsis. The synopsis is an overview of the larger weather picture. Fronts and major weather systems along or near the route of flight and weather that may affect the flight are provided.

• Current Conditions. This portion of the briefing contains the current surface weather observations, PIREPs, and satellite and radar data along the route of flight. If the departure time is more than 2 hours away, current conditions will not be included in the briefing.

• En Route Forecast. The en route forecast is a summary of the weather forecast for the proposed route of flight.

• Destination Forecast. The destination forecast is a summary of the expected weather for the destination airport at the estimated time of arrival (ETA).

• Winds and Temperatures Aloft. Winds and temperatures aloft is a forecast of the winds at specific altitudes along the route of flight. However, the temperature information is provided only on request.

• NOTAMs. This portion supplies NOTAM information that has not been published in the NOTAM publication, but is pertinent to the route of flight. Published NOTAM information is provided during the briefing only on request.

• Prohibited Areas and Special Flight Rules Areas (SFRA). Information on Prohibited Areas P-40 and P-56, and the SFRA for Washington, D.C. are given when appropriate to the route of flight.

• ATC Delays. This is an advisory of any known ATC delays that may affect the flight.

• Other Information. Any additional information requested is also provided at this time.

1.3.1.2 Abbreviated Briefing. An abbreviated briefing is a shortened version of the standard briefing. It should be requested when a departure has been delayed or when specific weather information is needed to update a previous standard briefing. When this is the case, the weather specialist needs to know the time and source of the previous briefing so he or she does not inadvertently omit the necessary weather information.

1.3.1.3 Outlook Briefing. An outlook briefing should be requested when a planned departure is 6 or more hours away. It provides initial forecast information that is limited in scope due to the timeframe of the planned flight. This type of briefing is a good source of flight planning information that can influence decisions regarding route of flight, altitude, and ultimately the “go, no-go” decision. A follow-up standard briefing prior to departure is advisable, since an outlook briefing generally only contains information based on weather trends and existing weather in geographical areas at or near the departure airport.

1.3.2 Pilot Briefing via the Internet. 

1.3.2.1 Direct User Access Terminal Service (DUATS II). DUATS II, an approved FAA preflight briefing source, allows any pilot to access NWS weather information and to file a flight plan online. Airmen can access DUATS II at http://www.duats.com, http://www.duatsii.com, or http://www.1800wxbrief.com. The current vendors of DUATS II service and the associated phone numbers are listed in the Aeronautical Information Manual (AIM), Chapter 7, Safety of Flight.

1.3.2.2 Aviation Digital Data Service (ADDS). ADDS is a joint effort of the FAA, NOAA, and the National Center for Atmospheric Research (NCAR). ADDS provides text, digital, and graphical forecasts, analyses, and observations of aviation-related weather variables.

1.3.3 Telephone Information Briefing Service (TIBS). TIBS is a service prepared and disseminated by Flight Service. It provides continuous telephone recordings of meteorological and aeronautical information. Specifically, TIBS provides area and route briefings, as well as airspace procedures and special announcements, if applicable. It is designed to be a preliminary briefing tool and is not intended to replace a standard briefing. The TIBS service is available 24 hours a day and is updated when conditions change. The order and content of the TIBS recording is as follows:

1. Introduction. Includes the preparation time and the route and/or the area of coverage. The service area may be configured to meet the individual facility’s needs.

2. Weather Advisories. A summary of in-flight advisories and any other available information that may adversely affect flight in the route/area.

TIBS services may be reduced during the hours of 1800 to 0600, local time only. Resumption of full broadcast service is adjusted seasonally to coincide with daylight hours. During the period of reduced broadcast, a recorded statement may indicate when the broadcast will be resumed and to contact Flight Service via the Internet or by telephone for weather briefing and other services.

For those pilots already in flight and needing weather information and assistance, the following services are provided by FSSs.

1.3.4 Hazardous In-flight Weather Advisory Service (HIWAS). HIWAS is a national program for broadcasting hazardous weather information continuously over selected Navigational Aids (NAVAID). The broadcasts include advisories such as AIRMETs, SIGMETS, Convective SIGMETs, and urgent PIREPs. These broadcasts are only a summary of the information, and pilots should contact an FSS for detailed information.

The HIWAS broadcast area is defined as the area within 150 NM of HIWAS outlets.

HIWAS broadcasts are not interrupted or delayed, except for emergency situations, when an aircraft requires immediate attention, or for reasonable use of the voice override capability on specific HIWAS outlets in order to use the limited remote communications outlet (RCO) to maintain en route communications. The service is provided 24 hours a day. An announcement is made for no hazardous weather advisories.

Hazardous weather information is recorded if it is occurring within the HIWAS broadcast area. The broadcast includes the following elements:

A statement of introduction including the appropriate area(s) and a recording time.

A summary of Convective SIGMETs, SIGMETs, AIRMETs, Urgent PIREPs, Aviation Watch Notification Messages (SAW), Center Weather Advisories, and any other weather, such as isolated thunderstorms that are rapidly developing and increasing in intensity, or low ceilings and visibilities that are becoming widespread, which are considered significant and are not included in a current hazardous weather advisory.

A request for PIREPs, if applicable.

A recommendation to contact FSS for additional details concerning hazardous weather.

Once the HIWAS broadcast is updated, an announcement will be made once on all communications/NAVAID frequencies, except emergency and navigational frequencies already dedicated to continuous broadcast services. In the event a HIWAS broadcast area is out of service, an announcement is made on all communications/NAVAID frequencies, except on emergency and navigational frequencies already dedicated to continuous broadcast services.

1.3.5 Flight Information Service-Broadcast (FIS-B). FIS-B is a ground-based broadcast service provided through the FAA’s Automatic Dependent Surveillance-Broadcast (ADS-B) Services Universal Access Transmitter (UAT) network. The service provides users with a 978 megahertz (MHz)F data link capability when operating within range and line of sight of a transmitting ground station. FIS-B enables users of properly-equipped aircraft to receive and display a suite of broadcast weather and aeronautical information products.

The following list represents the initial suite of textual and graphical products available through FIS-B and provided free-of-charge. This advisory circular (AC) and AC 00-63, Use of Cockpit Displays of Digital Weather and Aeronautical Information, contain detailed information concerning FIS-B meteorological products. AIM Chapter 3,

Airspace; Chapter 4, Air Traffic Control; and Chapter 5, Air Traffic Procedures contain information on Special Use Airspace (SUA), TFR, and NOTAM products.

  • Text: METAR and SPECI;
  • Text: PIREP;
  • Text: Winds and Temperatures Aloft;
  • Text: TAF;
  • Text: NOTAM Distant and Flight Data Center;
  • Text/Graphic: AIRMET;
  • Text/Graphic: SIGMET;
  • Text/Graphic: Convective SIGMET;
  • Text/Graphic: SUA;
  • Text/Graphic: TFR NOTAM; and
  • Graphic: Next generation weather radar (NEXRAD) Composite Reflectivity Products (Regional and National).

Users of FIS-B should familiarize themselves with the operational characteristics and limitations of the system, including: system architecture, service environment, product lifecycles, modes of operation, and indications of system failure.

Update intervals are defined as the rate at which the product data is available from the source for transmission. Transmission intervals are defined as the amount of time within which a new or updated product transmission must be completed and/or the rate or repetition interval at which the product is rebroadcast. Table 1-1, FIS-B Over UAT Product Update and Transmission Intervals, provides update and transmission intervals for each product.

Table 1-1. FIS-B Over UAT Product Update and Transmission Intervals

Table 1-1. FIS-B Over UAT Product Update and Transmission Intervals

Where applicable, FIS-B products include a look-ahead range expressed in nautical miles for three service domains: Airport Surface, Terminal Airspace, and En route/Gulf of Mexico. Table 1-2, Product Parameters for Low/Medium/High Altitude Tier Radios, provides service domain availability and look-ahead ranging for each FIS-B product.

Table 1-2. Product Parameters for Low/Medium/High Altitude Tier Radios

Table 1-2. Product Parameters for Low/Medium/High Altitude Tier Radios

Prior to using this capability, users should familiarize themselves with the operation of FIS-B avionics by referencing the applicable user’s guides. Users should obtain guidance concerning the interpretation of information displayed from the appropriate avionics manufacturer.

Users should report FIS-B malfunctions not attributed to aircraft system failures or covered by active NOTAM via the ADS-B/Traffic Information Services-Broadcast (TIS-B)/FIS-B Problem Report on the following website: http://www.faa.gov/exit/?pageName=this%20form&pgLnk=http%3A%2F%2Fgoo%2Egl%2Fforms%2FisWDKYpYYv. Users may also report malfunctions by submitting FAA Form 8740-5, Safety Improvement Report, via mail, fax, or email to your local Flight District Standards Office (FSDO) Safety Program Manager (SPM).

Users should obtain guidance concerning the content, format, and symbology of individual FIS-B products from the manufacturer of the avionics equipment used to receive and display them.

1.3.6 Operational Use of FIS-B Products. FIS-B information may be used by the pilot for the safe conduct of flight and aircraft movement. However, FIS-B does not replace a preflight briefing from an FSS via the phone, a Lockheed Martin Flight Services or DUATS II via the Internet, or dispatch/System Operations Control (SOC) (if applicable). A pilot should be particularly alert and understand the limitations and quality assurance issues associated with individual products. This includes graphical representation of NEXRAD imagery and NOTAMs/TFR.