The FIS officer (FISO) is a person who provides flight information service (FIS) and alerting service to aircraft in uncontrolled airspace (class G) or at an uncontrolled aerodrome. In the latter case the term AFISO (aerodrome FIS officer) is used. The FISO working position resembles that of the air traffic controller as they use similar equipment and communicate with pilots using standard phraseology. However, the working procedures differ significantly.
The key difference between an air traffic controller and a FISO is that the latter is not authorized to provide air traffic control service, i.e.:
- they are not responsible for collision avoidance and separation provision. They will, however, provide information (if available) about potentially conflicting traffic.
- they are not authorized to issue ATC clearances and instructions. They may, however, relay clearances and instructions, issued by air traffic controllers in neighbouring ATC units.
- they are not responsible for terrain and obstacle clearance. They will, however, advise the pilot if a terrain hazard is perceived (e.g. if an MSAW warning is activated)
While air traffic controllers may provide ATS in uncontrolled airspace (albeit limited to FIS and alerting service), FISOs are not allowed to provide service in controlled airspace. In the UK, where four types of FIS are defined in uncontrolled airspace ([[basic, traffic, deconfliction and procedural]]), FISOs may only provide basic service. The other three are only available to controllers.
Similarly to air traffic controllers, FISOs are licensed operators and must been validated for each aerodrome, or other air traffic control unit for which they work.
The callsign used by FISOs is "INFORMATION", preceded by the location indicator (FIR or aerodrome).
Communication is a vital part of the job: officers are trained to precisely focus on the exact words pilots and other controllers or FISOs use. As with controllers, FISOs communicate with the pilots of aircraft using a push-to-talk radiotelephony system, which has many attendant issues such as the fact only one transmission can be made on a frequency at a time, or transmissions will either merge or block each other and become unreadable.
Although local languages are sometimes used in ATC communications, the default language of aviation worldwide has been English since 5 March 2008, and in the United Kingdom, this is universal. As a result, flight information service officers require an excellent and fluent grasp of English. FISOs must be able to communicate without speech impediment or other disability which would cause inefficiency or inaccuracy of communication.
Provision of Information
The purpose of FIS is to provide advice and information useful for the safe and efficient conduct of flights. This includes:
- information about potentially conflicting traffic. Note that this information may not be available to the FISO, as flights (especially those flying VFR) in class G airspace may not establish radio communication, operate a transponder or even have a flight plan filed.
- weather informaiton, e.g. IMC information to VFR flights, messages AIRMET, SIGMET, TAF, etc.
- information about environmental factors (other than weather) that can affect flights (e.g. volcano eruptions, radioactive or toxic chemical clouds, etc.)
- special use area activation and deactivation
- informaiton about other hazards (e.g. distress traffic, fuel dumping, unmanned free baloons, etc.)
- other useful information (e.g. about radio aids)
Information can be provided using a general call to all stations on the frequency. This is useful when multiple aircraft need to be advised about a potential hazard. However, the preferred communication method is a directed message which is acknowledged by the pilot upon receipt.
Depending on the situation, FISOs may need to perform coordinaitons about aircraft that will leave their area of responsibility. If the next ATS unit provides air traffic control service, this will be mandatory, as the flight will need to obtain an entry clearance. If the neighbouring unit is also a FIS unit, then it is up to the concerned ATS units to define whether or not such flights are to be coordinated. The coordination is effected in accordance with the letter of agreement between the two units and will normally include at least:
- appropriate items of the current flight plan
- the time at which last contact was made with the aircraft
In case the aircraft is experiencing an emergency or its safety is otherwise not assured, this information is also passed to the accepting unit.
The tasks performed by the AFISO are similar to those of the FISO, i.e. they provide essential information to aircraft in the vicinity of uncontrolled aerodromes but are not responsible for collision avoidance and terrain clearance.
The information provided refers to a much smaller area, i.e. the manoeuvring area of the aerodrome and its vicinity and includes information about:
- the runway-in-use
- the altimeter setting
- other aircraft on the manoeuvring area or in the aerodrome traffic circuit
- vehicles and persons on the manoeuvring area
- weather (e.g. surface wind, visibility, temperature, significant weather, etc.)
- aerodrome conditions (e.g. contstruction works, runway and taxiway contamination, braking action, aerodrome lighting failure/degradation, etc.)
- radio bearings or direction-finding information, if appropriate equipment is available and certified for use
Note that the AFISO does not issue take off or landing clearances (or any other clearances) to aircraft. They only advise about the runway and traffic conditions. It is up to the pilot to decide whether to make a take-off/landing. However, AFISOs may be given authority to manage vehicles and other personnel on the manoeuvring area.
ICAO has not defined dedicated phraseology to be used by FISOs/AFISOs. In most situations (e.g. information provision, coordination, etc.), the general standard phraseology is applicable, especially during the cruise phase. Some states, e.g. the UK, have developed special phraseology to be used by AFISOs. For example, when an aircraft is ready for departure, the AFISO would use the phrase "NO REPORTED TRAFFIC. RUNWAY xx TAKE OFF AT YOUR DISCRETION" (instead of "CLEARED FOR TAKE OFF" which is only to be used by air traffic controllers).