Section 3. Operations

6-3-1. HANDLING OF SIGMETs, CWAs, AND PIREPs

a. SIGMETs and CWAs:

1. The CWSU meteorologist is the focal point for the review of SIGMETs to determine application to the ARTCC area of responsibility and may issue a CWA to modify or redefine the SIGMET information.

2. The CWSU meteorologist may also issue a CWA in advance of a SIGMET when the observed or the expected weather conditions meet SIGMET criteria or when conditions do not meet SIGMET criteria but are considered significant.

3. The weather coordinator (WC) has the primary responsibility for the inter/intrafacility dissemination of SIGMETs and CWAs and must ensure that sufficient information is disseminated to facilitate the required alert broadcasts.

4. Terminal ATC facilities must relay the SIGMET and the CWA information to towers under their jurisdiction.

b. PIREPs:

1. The WC is the focal point for handling PIREP requests and for the dissemination of Urgent PIREPs within the ARTCC and to the terminal ATC facilities without LSAS which are or may be affected.

2. The CWSU meteorologist solicits PIREPs through the weather coordinator or directly from the controllers when required. Both solicited and unsolicited PIREPs that meet the Urgent PIREP criteria will be distributed immediately via the Leased Service A System (LSAS).

c. PIREP classification: Categorize PIREPs as follows:

1. URGENT: Weather phenomena reported by a pilot which represents a hazard or a potential hazard to flight operations. Disseminate reports of the following conditions as URGENT PIREPs:

(a) Tornadoes, funnel clouds, or waterspouts.

(b) Severe or extreme turbulence (including clear air turbulence).

(c) Severe icing.

(d) Hail.

(e) Low level wind shear.

NOTE-
Defined as wind shear within 2,000 feet of the surface.

(f) Volcanic eruptions and volcanic ash clouds.

(g) Any other weather phenomena reported which are considered by the specialist as being hazardous or potentially hazardous to flight operations.

2. ROUTINE: Classify as ROUTINE all PIREPs received except those listed above.

6-3-2. RECEIPT OF NOTAM DATA

ARTCC air traffic managers must coordinate with other air traffic facilities in their area to ensure that adequate procedures are established for the receipt and distribution of NOTAMs.

6-3-3. DF NET CONTROL POSITION OPERATION

The FSS in whose area the DF service is requested must have full responsibility for all DF activities until the aircraft has been located or has passed into an adjacent FSSs flight plan area; then, responsibility must be transferred to the receiving FSS. DF Net control facilities must be assigned by the En Route and Oceanic Operations Area Office Director. DF Net control must not be assigned to FSS facilities, until such time as a telephone system, equal to or better than the ARTCC system, is fully operational to appropriate adjacent facilities.

a. Provide maximum assistance to the aircraft in distress. Priority should be given to establishing radar contact with an aircraft in distress. When an aircraft directly contacts a DF facility and requests assistance, that facility must:

1. Coordinate with the appropriate radar facility to establish radar contact by using code 7700 or a discrete beacon code assigned by the radar facility.

2. Provide any necessary assistance to the aircraft and coordinate with the appropriate control facility when radar contact cannot be established.

b. When requested by the DF Facility, the ARTCC must function as a relay agent to assist in alerting and for coordination between control facilities and DF locations.

NOTE-
ARTCCs acting as relay agents may become necessary due to line outages or other direct communication disruption between DF facilities.

c. Radar control facilities must alert DF facilities that might be able to provide service whenever radar contact cannot be established and one of the following conditions exist:

1. A pilot becomes lost or disoriented.

2. An emergency is declared.

NOTE-
DF facilities that might be able to provide service should still be alerted as a backup method of assistance, especially if loss of radar contact or loss of transponder is a concern.

d. An ARTCC may request assistance from military aircraft to provide UHF/VHF DF bearing information. However, the aircraft commander retains the prerogative as to the availability of this service.

e. Emergency DF operations will normally be conducted on emergency frequency 121.5 MHz. If the aircraft in distress is unable to utilize 121.5 MHz, a discrete frequency may be used. Also, discrete frequencies should be used for practice DFs.

f. It must be the responsibility of DF stations to maintain a satisfactory level of operator proficiency. DF stations must devise forms to satisfactorily record incidents of navigational assistance provided to aircraft, DF training activities, and for recording inoperable status. Voice recordings of DF service to aircraft must be as prescribed for normal ATC requirements at each DF facility.

6-3-4. REVIEW AIRSPACE STRUCTURE

Although magnetic radials are used in planning airways/routes, conversion to true radials is required for designation. The final magnetic radials are not determined until the airspace action is charted. As a result, differences from planned magnetic radials may occur in the conversion of true to magnetic radials. Differences may also occur later due to changes in the magnetic variation, which is recomputed every 5 years. These differences could contribute to the misapplication of the VFR altitude hemispheric rule. Therefore, ARTCC air traffic managers must conduct a continuing review of the airway and jet route structures and proposed new airspace cases and bring any differences to the attention of the En Route and Oceanic Operations Service Area Office.

6-3-5. DATA COMMUNICATION

ARTCC air traffic managers must furnish personnel assigned Flight Data duties a copy of FAAO JO 7110.10, Flight Service, and ensure they are familiar with it.

6-3-6. MTR (IR) AND CHANGES TO PUBLISHED MOA ACTIVITY SCHEDULES

a. ARTCCs must use the procedures as outlined in FAAO JO 7110.10, Flight Services, para 6-5-1 for forwarding these schedules or changes via Service B.

NOTE-
Facilities may develop procedures for forwarding these scheduled MTR/MOA via the GI message provided the “all” option is not utilized and there is no adverse impact on computer processing.

b. The message(s) containing these schedules must be forwarded not more than 24 hours in advance of confirmation of the planned activity.

c. The message must only contain the following and be formatted as per FAAO JO 7110.10, Flight Services, para 6-5-1:

1. The name of the MTR or MOA.

2. The scheduled use times.
(MOA-only if different from published periods).

3. The planned altitudes.
(MOA-only if different from published altitudes).