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Self Briefing is the process of utilising printed or electronically sourced data to make oneself sufficiently familiar with both the actual and forecast weather conditions that are pertinent to the intended flight. Done properly, the process will enable informed decisions en route and altitude selection, choice of alternate and diversion aerodromes, fuel requirements, and ensure compliance with any applicable regulations.
Prior to the aviation community's almost universal access to the internet, the infrastructure at virtually all international (and most regional) airports included the provision of a professionally staffed weather services office. These offices were often co-located with Airport Operations or included as part of a Flight Service Station (FSS) and were staffed by professional observers, briefers and, in some locations, meteorologists. As a matter of routine, most military, corporate and general aviation (GA) pilots (and, in some cases, air navigators) would attend the weather office, as part of their preflight or transit stop routine. There, they would acquire the most current weather information and be professionally briefed on the weather phenonmena that they might encounter along their route of flight. During the same era, most airlines had an operations office at each major hub and their pilots would receive their weather briefing from professional dispatchers as part of the preflight protocol. Over time, automation advances and budgetary constraints reduced the availability these facilities, and the associated professional staff, as they were consolidated into regional offices. However, pilots could still use the telephone to call the appropriate regional office to obtain a full weather briefing. With the advent of online flight plan filing and provision of weather information services, fewer and fewer pilots made use of the services of a weather office when obtaining their preflight briefing, instead downloading the information from online sources or by being forwarded the flight "package" from airline dispatch or a third-party provider, and then self briefing. Whilst self briefing can provide an equivalent level of safety, if not done properly it can leave the fight crew without an adequate understanding of the weather phenomena that could affect their flight.
Weather, and weather-related phenonmena, affect all phases of flight. Consequently, a preflight briefing sufficient to obtain an adequate understanding of the existing and forecast weather conditions is essential to flight safety. Numerous accident and incident reports, most significantly involving General Aviation (GA) VFR flights, have cited lack of weather awareness as a causal or contributing factor. Whilst there are ample sources available from which to obtain the information required to conduct an adequate self brief, there are also a number of impediments to making this happen. These include:
- Time - historically, the time allocated for preflight planning and preparation was typically in the range of 90 minutes to two hours, even for a crew that included a flight engineer, an air navigator and, possibly, a load master or cargo specialist. With advancing technologies and computer-generated flight plans, the standard flight crew now consists of two pilots. The allocated time for preflight duties has been reduced to as little as 30 minutes (with 60 as the "norm") to maximise crew utilisation in a regulatory environment of more restrictive duty day limitations. This often leads to only one pilot reviewing the weather whilst the other addresses other facets of the preflight preparation
- Scope - some service providers include a brief synopsis of the weather with the flight package, highlighting significant weather and en route risks, and then tailor the information provided in the rest of the package to the specific requirements of the route and aircraft type. Others do not provide a synopsis and often include an overwhelming amount of extraneous data, often numbering 30 pages or more, making it difficult, and time consuming, to extract the pertinent information. Many pilots limit the scope of their self briefing to a review of the actual and forecast conditions for origin, en route diversion, destination and alternate aerodromes, omitting an examination of significant weather, en route conditions and potential hazards
- Interpretation - many pilots, most often those flying in the general aviation, privately owned or hired aircraft community, have little (or no) formal training in the interpretation of weather products
- Complacency - individuals that fly the same route(s) to a limited number of destinations, or planning to remain in the vicinity of their departure airfield, may become complacent as "the weather rarely changes"
- Corporate pressures - early arrival of a Business Aviation client can lead to the truncation, or the complete elimination, of the self brief as the crew shifts their priority to getting airborne as quickly as possible in an effort to reduce any customer delay
Avoiding complacency and briefing adequately will provide sufficient understanding of the en route and terminal weather to allow an educated "go, no-go" decision, a sensible route and altitude selection, the appropriate choice of alternate and/or diversion aerodromes and to facilitate the calculation of an appropriate fuel load to ensure safety of flight. The challenges identified in the previous section can be overcome using some of the following strategies:
- Time - preflight time is almost always limited. Organise, prioritise and delegate as appropriate. Time can be saved by conducting an initial weather review in advance of the flight. Previewing the weather 12-24 hours in advance of a complex flight can provide insight into the expected conditions, allow preselection of route, altitude and alternate aerodromes and identify specific areas that will require closer examination just prior to execution
- Scope - seek a service provider that will tailor the weather package to the specific flight and aircraft type and that provides a synopsis as well as the appropriate diversity in weather products. When self-selecting the weather products to review, ensure that they afford a true picture of the weather likely to be encountered
- Interpretation - ensure that you are conversant with, and able to decode, all relevant meteorological information including graphical presentations such as Surface Analysis and Significant Weather charts and alphanumeric products such as TAFs and METARs. Both on-line and in-person instructional courses are available from NAA certified sources
- Complacency - weather, and weather-related phenomena, affect all phases of flight. Pilots should acknowledge that perspective as a fundamental truth. In doing so, it will help to ensure that the self briefing for every flight, be it a short trip to the local practice area, a regional cross country or a transoceanic, international flight, will be appropriate and identify any weather hazards that might affect the flight
- Corporate pressures - if duty day constraints allow, arrange your preflight duties to be ready to "turn engines" 30-40 minutes before the published departure time. If passengers arrive before preflight preparation is complete, be prepared to board them or hold them in the departure lounge, but delay start until you are ready.
Almost all government and commercial training agencies suggest a "top down" approach to the weather self briefing. This methodology begins with an overview of the "big picture" international, national or regional conditions (as appropriate to the flight) and finishes with the examination of the actual conditions at the point of departure, destination and alternate airports, and at selected locations along the route of flight. Although there is some variance in the guidance from different agencies, the suggested methodology generally conforms with the following steps:
- Begin by reviewing charts which provide a large scale overview of the flight route. The Surface Analysis chart and AIRMET/SIGMET maps will provide a high level perspective of weather systems and areas of hazardous weather
- While maintaining a "large scale" focus, move on to prognostic charts such as Convective Forecasts, Icing Forecasts, Freezing Level Forecasts and Turbulence Forecasts
- The next task should be an examination of en route winds and temperatures. Winds Aloft forecasts come in both graphical and textual format. The graphical format is generally more convenient for altitude selections and temperature considerations
- Graphical prediction products, that indicate widespread areas of cloud ceilings and visibilities, are available for many regions. These are easier to interpret than traditional weather depiction charts and offer analysis as well as forecast time periods
- The final step of the forecast examination is a review of applicable TAF products from your departure aerodrome to your destination including diversion airports and alternates
With the forecast review complete, move on to an examination of current conditions, again using a "top down" approach.
- Begin with satellite and radar imagery to provide a large scale overview of current conditions
- Review any available PIREPS. Keep in mind the type of aircraft that provided the report and how that might translate to your aircraft type in the same weather phenomena
- Complete the review with an examination of the current conditions at your departure, destination, diversion and alternate airports using METARs or graphical charts of current conditions
With the forecast and actual conditions review complete, conclude the self briefing by comparing the current conditions with the corresponding forecast information to determine if the forecasts are accurate or if conditions are changing more quickly or more slowly than expected. As previously stated, this is only a suggested sequence. Other methodologies could be used and, providing they review much the same information, be equally effective.
A clear understanding, by the flight crew, of the weather that could affect their flight, is a strong contributor to safety of flight. Both in-person and telephone based briefings have given way to a self briefing process by which crews familiarise themselves with the weather using online or printed products. Self briefing can provide an equivalent level of safety but only if the flight crew is capable of interpreting the available weather products and if they conduct their weather review in a systematic and comprehensive fashion.
Accidents and Incidents
- DHC2, Squaw Lake Quebec Canada, 2005 (On 1st September 2005, a DHC-2 Beaver, crashed near Squaw Lake, Quebec, Canada, following loss of control in poor weather and moderate to severe turbulence.)
- L410, Isle of Man, 2017 (On 23 February 2017, a Czech-operated Let-410 departed from Isle of Man into deteriorating weather conditions and when unable to land at its destination returned and landed with a crosswind component approximately twice the certified limit. The local Regulatory Agency instructed ATC to order the aircraft to immediately stop rather than attempt to taxi and the carrier’s permit to operate between the Isle of Man and the UK was subsequently withdrawn. The Investigation concluded that the context for the event was a long history of inadequate operational safety standards associated with its remote provision of flights for a Ticket Seller.)
- SF34, Marsh Harbour Bahamas, 2013 (On 13 June 2013, a rushed and unstable visual approach to Marsh Harbour by a Saab 340B was followed by a mishandled landing and a runway excursion. The Investigation concluded that the way the aircraft had been operated had been contrary to expectations in almost every respect. This had set the scene for the continuation of a visual approach to an attempted landing in circumstances where there had been multiple indications that there was no option but to break off the approach, including a total loss of forward visibility in very heavy rain as the runway neared.)
- CRJ1, Kinshasa Democratic Republic of Congo, 2011 (On 4 April 2011, the crew of a Georgian Airways Bombardier CRJ100 operating a domestic flight for the United Nations lost control of their aircraft as they commenced a go around from below the MDA for the non precision approach flown due to an absence of visual reference with the runway. They were aware from their weather radar of severe convective weather in the vicinity of the airport although the METAR passed by ATC did not indicate this. The aircraft crashed alongside the runway and was destroyed. All occupants except one who was seriously injured were killed.)
- B738, vicinity Trivandrum India, 2015 (On 18 August 2015, a Boeing 737-800 made three unsuccessful ILS approaches at Cochin around dawn then diverted to Trivandrum where a day VOR approach was unsuccessful and a MAYDAY was declared due low fuel. Two further supposedly visual approaches were attempted there before a third such "visual" approach - which involved ignoring EGPWS PULL UP Warnings in IMC - was followed by a successful landing with 349kg fuel remaining. The Investigation found that aircraft safety had been jeopardised and that Cochin ATC had not communicated information on the deteriorating weather at Trivandrum. Relevant operator procedures were considered as inadequate.)