Information through the flight
Meteorological information supports planning before flight, decisions at dispatch and updates in flight. The pilot needs information that matches route, level, aerodrome and time rather than a large undirected collection of reports.
Before and after departure
Before flight, establish the baseline route, levels, aerodromes and alternates. In flight, obtain the latest reports, forecasts and warnings early enough to act on them.
Use validity
A current observation, a forecast and a warning serve different purposes. Note their issue and validity times before comparing them.
Briefing documentation
Joshi describes briefing timing, oral briefing, documents and data. Met T3 and T4, high and low SIGWX charts, national and international material and route-specific documents form a structured briefing rather than separate items.
Read the document set
Check issue time and validity, route coverage and level reference. Then identify cloud, weather, wind, temperature, freezing and significant weather by route section.
Oral briefing
An oral briefing should explain the weather story and uncertainties. It should not simply recite codes. The crew must know what changes the plan and when it will be reviewed.
VOLMET and D-VOLMET
VOLMET gives meteorological information to aircraft in flight. Broadcast and data-link forms carry routine reports and forecasts in a usable in-flight form. Joshi lists METAR, SPECI, TAF, SIGMET and relevant special reports within this service context.
VHF and HF
VHF VOLMET serves local or regional use. HF VOLMET supports long-range routes, including North Atlantic operations, in the HF band. The channel and published schedule determine availability.
Use the update
Compare a received report with the earlier planning data. Update approach, fuel or alternate thinking when the new information changes the risk.
ATIS operation
ATIS provides a recorded arrival or departure information set. It includes relevant weather and aerodrome data and changes by sequential alphabet letter. The pilot reports the received information letter to ATC.
Contents and acknowledgement
ATIS supports a shared current picture between crew and controller. It can include runway, approach, wind, visibility, cloud, temperature, QNH and significant operational information.
Do not freeze the plan
ATIS is a snapshot. If conditions are changing, compare it with the latest ATC instruction, METAR, warning and approach requirement.
Updates in flight
In flight, routine information is supplemented by urgent changes. SIGMET, AIREP, volcanic-ash and tropical-cyclone information can require rerouting, level change, diversion or an early alternate decision.
Compare source strengths
Satellite and radar show extent and movement. Reports show observed conditions. Charts and forecasts show expected evolution. No single source has every answer.
Act early
The best time to reassess a deteriorating destination is before the fuel and routing options shrink. Make the update cycle part of the flight plan.
Complete briefing workflow
A domestic or international flight needs the same discipline: begin with valid documents, build the route picture, receive in-flight updates and compare them with the original forecast. Products differ by region, but the reasoning remains the same.
Cross-checks
Use METAR and TAF for aerodromes, SIGWX and route products for en route, warnings for hazards and VOLMET or ATIS for current operational updates.
Decision record
Record the intended route and level, weather threats, alternates, fuel consequence and next update. This makes changing conditions manageable rather than surprising.
ATIS and VOLMET used correctly
VHF VOLMET provides routine broadcasts for local or regional flights. HF VOLMET, in the 3 to 20 MHz range, supports longer routes including North Atlantic operations. D-VOLMET provides data-link access to current METAR, SPECI, TAF, SIGMET and relevant special reports. A spoken report must still be checked for station and issue time.
ATIS is an arrival or departure recording. It gives operational aerodrome information such as runway, approach, wind, visibility, cloud, temperature, QNH and significant information. Each substantial update receives the next alphabet letter. The pilot reports that letter to ATC; the controller can then confirm that both are using the same information set. Joshi's briefing material requires the crew to use Met T3/T4, high and low SIGWX and current warnings by route sector, not as a pile of unrelated documents.
Briefing material by flight phase
- Before departure compare departure and destination METARs, TAFs, route SIGWX, winds and temperatures, alternates and all current warnings.
- At dispatch confirm validity periods and identify the latest update expected before the critical route or arrival time.
- In flight use VOLMET or D-VOLMET for routine updates, ATIS before arrival, and SIGMET or special aircraft reports for urgent changes.
AIREP information can reveal cloud, turbulence, icing or wind conditions not obvious in a routine report. Treat it as an observation at its stated position, level and time. It adds value when compared with the forecast and other reports from the same area.
ATIS acknowledgement example
An arrival crew obtains ATIS Information Bravo, notes the runway, wind, visibility, cloud, QNH and reported weather, and advises ATC: 'Information Bravo received.' If ATC later issues Information Charlie, the earlier data is not assumed to remain current. The crew obtains Charlie, compares the changed item with approach minima and alternate fuel, then reports the new letter.
Chart and broadcast cross-check
Before a domestic or international flight, use written documentation to establish the route picture, then use broadcasts to update it. A MET T3/T4 chart supports wind and temperature planning; high and low SIGWX charts support hazard planning. VOLMET gives a current operational summary for selected stations. ATIS gives the current terminal set. A warning can supersede an earlier benign picture if it affects the planned route and time.
The information letter is a control tool. Reporting it to ATC tells the controller which ATIS set the crew has received. If the runway, visibility, QNH or approach changes, obtain the newer letter and revise the approach or alternate calculation.
Broadcast discipline
Copy only the elements that affect the current plan, but retain station, time and information letter. A report without its time cannot be compared reliably with a forecast. If destination weather is close to minima, obtain the next scheduled update before committing to a route or holding decision.