Aeronautical Information Manual (AIM), page 462

Index   461 -- Page 462 -- 463


7-1-10. Flight Information Services (FIS)

a. FIS. FIS is a method of disseminating

meteorological (MET) and aeronautical information

(AI) to displays in the cockpit in order to enhance

pilot situational awareness, provide decision support
tools, and improve safety. FIS augments traditional
pilot voice communication with Flight Service
Stations (FSSs), ATC facilities, or Airline Operations
Control Centers (AOCCs). FIS is not intended to
replace traditional pilot and controller/flight service
specialist/aircraft dispatcher preflight briefings or
inflight voice communications. FIS, however, can
provide textual and graphical information that can
help abbreviate and improve the usefulness of such
communications. FIS enhances pilot situational
awareness and improves safety.
1. Data link Service Providers (DLSP) - DLSP
deploy and maintain airborne, ground-based, and, in
some cases, space-based infrastructure that supports
the transmission of AI/MET information over one or
more physical links. DLSP may provide a free of
charge or for-fee service that permits end users to
uplink and downlink AI/MET and other information.
The following are examples of DLSP:
(a) FAA FIS-B. A ground-based broadcast
service provided through the ADS-B Universal
Access Transceiver (UAT) network. The service
provides users with a 978 MHz 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 informa-
tion products.

(b) Non-FAA FIS Systems. Several commer-
cial vendors provide customers with FIS data over
both the aeronautical spectrum and on other
frequencies using a variety of data link protocols.
Services available from these providers vary greatly
and may include tier based subscriptions. Advance-
ments in bandwidth technology permits preflight as
well as inflight access to the same MET and AI
information available on the ground. Pilots and
operators using non-FAA FIS for MET and AI
information should be knowledgeable regarding the
weather services being provided as some commercial
vendors may be repackaging NWS sourced weather,
while other commercial vendors may alter the
weather information to produce vendor-tailored or
vendor-specific weather reports and forecasts.

2. Three Data Link Modes. There are three data
link modes that may be used for transmitting AI and

MET information to aircraft. The intended use of the

AI and/or MET information will determine the most

appropriate data link service.

(a) Broadcast Mode: A one-way interaction
in which AI and/or MET updates or changes
applicable to a designated geographic area are
continuously transmitted (or transmitted at repeated
periodic intervals) to all aircraft capable of receiving
the broadcast within the service volume defined by
the system network architecture.
(b) Contract/Demand Mode: A two-way
interaction in which AI and/or MET information is
transmitted to an aircraft in response to a specific
(c) Contract/Update Mode: A two-way inter-
action that is an extension of the Demand Mode.
Initial AI and/or MET report(s) are sent to an aircraft
and subsequent updates or changes to the AI and/or
MET information that meet the contract criteria are
automatically or manually sent to an aircraft.
3. To ensure airman compliance with Federal
Aviation Regulations, manufacturer's operating
manuals should remind airmen to contact ATC
controllers, FSS specialists, operator dispatchers, or
airline operations control centers for general and
mission critical aviation weather information and/or
NAS status conditions (such as NOTAMs, Special
Use Airspace status, and other government flight
information). If FIS products are systemically
modified (for example, are displayed as abbreviated
plain text and/or graphical depictions), the modifica-
tion process and limitations of the resultant product
should be clearly described in the vendor's user

4. Operational Use of FIS. Regardless of the
type of FIS system being used, several factors must
be considered when using FIS:
(a) Before using FIS for inflight operations,
pilots and other flight crewmembers should become
familiar with the operation of the FIS system to be
used, the airborne equipment to be used, including its
system architecture, airborne system components,
coverage service volume and other limitations of the
particular system, modes of operation and indications
of various system failures. Users should also be
familiar with the specific content and format of the
services available from the FIS provider(s). Sources

7-1-18 Meteorology

Page 462 of the Aeronautical Information Manual (AIM.pdf)
AIM: Official Guide to Basic Flight Information and ATC Procedures

Index   461 -- Page 462 -- 463