Learning Goals 4h, 4i notes PDF

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Notes on Identifying thunderstorm hazards to flight & how to avoid them. Heavy rain. and Access government sources of aviation weather observations, analyses, and forecasts....

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iFlying Weather https://www.eoas.ubc.ca/courses/atsc113/flying/definitions/jargon.html (keywords) Learning Goal 4h. Identify thunderstorm hazards to flight & how to avoid them. Heavy rain. ● hazard associated with rain is reduced visibility , with heavier rains having poorer visibility ○ if you are flying VFR (visual) you might need to fly around heavy rain areas in order to remain in regions with sufficiently good visibility. ● the heaviest part of thunderstorm rain usually happens in isolated showers of diameters ranging from 1 to 15 km, ○ you can often fly around them. ○ exception is a squall line, where there is a nearly continuous line (100s to 1000s km long, but often only 15 km wide) of heavy rain ● ingestion of very heavy rain into a turbine engine can cause it to stop. ○ Canadian TC-AIM states: ○ "If the updraft velocity in the thunderstorm approaches or exceeds the terminal falling velocity of the falling raindrops, very high concentrations of water may occur. It is possible that these concentrations may exceed the quantity of water that a turbine engine is capable of ingesting. Therefore, severe thunderstorms may contain areas of high water concentration which could result in a flameout or structural failure of one or more engines." ● Many business jets and airlines have airborne weather radar, so they can detect heavy rain cells and change their flight path to avoid the heaviest rain. ● For smaller aircraft without radar, information on the location of thunderstorm cells can be obtained by talking on the radio to weather briefers on the ground (flight-service-station specialists), because the briefers have access to ground-based weather radar images and pilot reports. ○ many pilots can view ground-base weather radar on personal mobile electronic pads and smart phones. ○ in general, light rain is blue, moderate is green, heavy is red, and very heavy rain or hail is purple or white. Learning Goal 4i. Access government sources of aviation weather observations, analyses, and forecasts. ● Aviation Weather Web Site (AWWS) In Canada ● Aviation Weather Center (AWC), In USA ● Different types of weather products available ○ surface weather map (analysis & forecasts) — for the big picture overview of fronts, lows, highs ○ satellite images of clouds ○ radar images of rain and storms ○ regions of nice flying weather (VFR), not such nice flying weather (MVFR), and bad weather where pilots need to fly on instruments (IFR). ○ weather hazards overview map, including VFR vs. IFR, turbulence, icing, SIGMETs (warnings of significant weather hazards) ○ turbulence (from pilot reports, aircraft reports, and SIGMETS) ○ icing (from pilot reports, aircraft reports, and SIGMETS) ○ convection / thunderstorms (from various sources and radar) ○ ceiling and visibility ○ wind and temperature at different flight altitudes ○ pilot reports (PIREPs) and aircraft reports (AIREPs) of weather, made from aircraft in flight ○ airmans meteorological advisories (AIRMETs) and significant meteorological (SIGMETs) advisories ○ volcanic ash ○ current-weather observations at airports (METARs & SPECIs) ○ weather forecasts at airports (TAFs) ● Pilots use METARs to learn the current observed weather at their departure airport, destination airport, and other airports near the flight track. ○ text (not graphics) that are coded using acronyms, abbreviations, and special formats. ○ METARs are reported every hour, routinely ○ Only tell us current weather, not the future weather ● TAFs are forecasts of the future weather, produced by meteorologists using sophisticated computer simulations of the atmosphere. ○ can access these text-format TAFs the same way that they get METARs. - also coded...