Section 2. Transcribed Weather Broadcasts (TWEB) (Alaska Only)

2-2-1. GENERAL

a. Transcribed weather broadcast service provides continuous aeronautical and meteorological information on L/MF and VOR facilities.

b. At TWEB equipment locations controlling two or more VORs, the one used least for ground-to-air communications, preferably the nearest VOR, may be used as a TWEB outlet simultaneously with the NDB facility. Where this is accomplished, capability to manually override the broadcast shall be provided for emergency communications.

2-2-2. CONTENT

User needs should dictate the content of these recordings. Required items are denoted with an asterisk (*).

a. *Introduction. State the preparation time.

PHRASEOLOGY-
TRANSCRIBED AVIATION WEATHER BROADCAST PREPARED AT (time) ZULU.

b. *Adverse Conditions. Extracted from WST, WS, WA, CWA and AWW.

PHRASEOLOGY-
WEATHER ADVISORIES ARE IN EFFECT FOR (adverse conditions) OVER (geographical area) (summary).

c. Synopsis. A brief statement describing the type, location, and movement of weather systems and/or masses which might affect the route or the area.

d. TWEB Route Forecasts. Broadcast from appropriate forecast data. Include the valid time of forecasts.

PHRASEOLOGY-
ROUTE FORECAST(S) VALID UNTIL (time) ZULU.

e. Winds Aloft Forecast. Broadcast winds aloft forecast for the location nearest to the TWEB. The broadcast should include the levels from 3,000 to 12,000 feet, but shall always include at least two forecast levels above the surface.

PHRASEOLOGY-
WINDS ALOFT FORECAST VALID UNTIL (time) ZULU. (Location) (Altitude) (direction) AT (speed).

f. Radar Reports (RAREP). Use local or pertinent RAREPs. If the facility has access to real time weather radar equipment, summarize observed data using the RAREPs to determine precipitation type, intensity, movement, and height.

g. *Surface Weather Reports. Record surface reports as described in para 2-1-6, Weather Report Phraseology.

1. Broadcast local reports first, then the remainder of the reports beginning with the first station east of true north and continuing clockwise around the TWEB location.

2. Announce the location name of a surface report once.

(a) Surface weather broadcast introduction:

PHRASEOLOGY-
AVIATION WEATHER, (4 digits of time), ZULU OBSERVATIONS.

(b) Special weather reports:

PHRASEOLOGY-
(Location name) SPECIAL REPORT (last 2 digits of time) OBSERVATION, (weather report).

h. *Density Altitude. Include temperature and the statement "CHECK DENSITY ALTITUDE" as part of the surface weather broadcast for any station with a field elevation of 2,000 feet MSL or above that meets the following criteria: (See TBL 2-2-1.)

TBL 2-2-1
Density Altitude

i. Pilot Weather Reports. Summarize PIREPs and, if the weather conditions meet soliciting requirements, append a request for PIREPs.

1. Summary.

PHRASEOLOGY-
PILOT WEATHER REPORTS SUMMARY (text).

2. *Request for PIREPs, if applicable.
(See para 9-2-5, Soliciting PIREPs.)

PHRASEOLOGY-
PILOT WEATHER REPORTS ARE REQUESTED (location, area) FOR (cloud tops, icing, turbulence, etc.).

j. *ALNOT Alert Announcement, if applicable.

PHRASEOLOGY-
OVERDUE AIRCRAFT ALERT, (time) ZULU (aircraft identification), (color), (type), DEPARTED (airport) VIA (route), (destination). LAST KNOWN POSITION (state last known position). THIS AIRCRAFT IS OVERDUE. ALL AIRCRAFT ARE REQUESTED TO MONITOR ONE TWO ONE POINT FIVE FOR E-L-T SIGNAL. INFORM THE NEAREST F-A-A FACILITY OF ANY INFORMATION REGARDING THIS AIRCRAFT.

k. *Closing statement.

PHRASEOLOGY-
FOR NOTAM, MILITARY TRAINING ACTIVITY, OR OTHER SERVICES, CONTACT A FLIGHT SERVICE STATION.

2-2-3. TESTING TWEB EQUIPMENT

When TWEB equipment is to be tested, broadcast an advisory to this effect. Care shall be exercised to ensure no obsolete information is broadcast during a testing period.

2-2-4. SERVICE MAY BE SUSPENDED

TWEB service may be suspended:

a. For routine maintenance only during periods when weather conditions within 100 miles of the broadcast outlet are equal to or better than a ceiling of 3,000 feet and visibility of 5 miles.

b. When the equipment fails. If a malfunction occurs in the recording or control unit but the tape transport unit remains operative, continue broadcasting current data. Remove data as it becomes obsolete.

2-2-5. MONITORING

a. At TWEB equipment locations, listen to at least one complete TWEB cycle each hour. Check for completeness, accuracy, speech rate, and proper enunciation. Correct any noted irregularities.

b. If practical:

1. The control facility shall monitor the transmissions through local outlet.

2. The AFSS/FSS associated with a remote outlet shall monitor the transmissions for a sufficient period each hour to assure voice quality and clarity.

c. Promptly correct or inform the TWEB facility of any irregularities.