Section 4. Application

4-4-1. OPERATIONS UNDER EXEMPTIONS FROM SECTION 3 OF APPENDIX D TO PART 91 SURFACE AREAS OF CLASS B AND CLASS C AIRSPACE WITHIN WHICH SPECIAL VFR WEATHER MINIMUMS ARE NOT AUTHORIZED FOR FIXED-WING AIRCRAFT

Implement LOAs with operators whose operations are conducted under an exemption to 14 CFR part 91, appendix D, section 3. Letters of Agreement should contain:

The surface area within which exempted operations may be conducted;
The weather minimums required for the operations;
That visual reference to the surface is required;
Sufficient details as to routes, altitudes, communications, reporting points, etc. to facilitate control of these operations;
Code names, if practical, for use in signifying to the pilot the details of each arrival and departure procedure; and
Any additional data which the ATC facility believes necessary to accommodate operations.

NOTE-

14 CFR part 91, appendix D, section 3 lists specific surface area locations in which FW/SVFR flight is prohibited. However, operators may petition for exemptions from these prohibitions. An exemption may only be granted by an FAA Headquarter's office (i.e., Vice President for Terminal Services, or the Administrator).

4-4-2. USE OF AIRCRAFT CALL SIGNS

Local call sign/telephony designators are authorized for use only for local flight operations as specified in a letter of agreement (LOA) between the local air traffic control (ATC) facility(ies) and the requesting aircraft operator. LOAs concerning the use of aircraft call signs by local flight operators must conform with the following standards:

Local call signs must not be assigned a three-letter designator to ensure they do not conflict with ICAO three-letter designators (ICAO 3LDs). Local call signs may be assigned 2, 4, 5, and 6 letter call sign designators.
Local call sign/telephony designators must not conflict with call signs and/or telephonies in use by military aircraft and other aircraft that operate in the local area.

NOTE-

According to Army Regulation (AR) 95-2, Air Traffic Control, Airfield/Heliport, and Airspace Operations, U.S. Army aviation units are not authorized to obtain call signs or enter into call sign agreements with local or regional ATC agencies (i.e., local FAA ATC facilities). The point of contact for U.S. Army aviation units requesting a call sign is the U.S. Army Aeronautical Services office via email at usarmy.belvoir.tradoc.list.usaasaops@mail.mil.
Local call signs are only used for communications and operations with local ATC facilities that are signatories on the LOA.
Local call signs are not used in filing flight plans outside the local area designated in the LOA.

NOTE-

Certain aircraft operators, such as aircraft manufacturers or law enforcement, may request a U.S. special call sign/telephony designator that would enable IFR flight operations outside the designated local area.

REFERENCE-

FAA Order JO 7610.12, Assignment and Authorization of Call Sign Designators and Associated Telephonies.
AC 120-26, Assignment of Aircraft Call Signs and Associated Telephonies.

4-4-3. RUNWAY SUPERVISORY UNITS (RSU)

Facility air traffic managers must ensure that the following items are included in a LOA with the local military authority when the operation of a military RSU has been directed by the military commander.

Qualification requirements of personnel operating the RSU.
A continuous monitor of the appropriate tower frequency is maintained.
Coordination with the tower is accomplished prior to changing to an alternate frequency.
The primary function of the RSU is to monitor arrivals and departures of designated military aircraft.
The RSU must not be used for ATC service except:
1. In an emergency situation; or
2. At undergraduate pilot training/pilot instructor training (UPT/PIT) locations to UPT/PIT aircraft for preventive control purposes.
Radio silence must be maintained at all times unless actual safety of flight is involved or as outlined in subparagraph e above.