WeatherMan

Weather Gathering: The Science and Art of Pre, Intra and Postflight

January 01, 20256 min read

Every human on this earth is affected by the weather. My grandfather straightforwardly explained the weather to me as a young seven-year-old. Open the window and stick your head out. If your head gets wet, it is raining. If your hair gets blown, it is windy. Wet your finger and stick it straight up; you will know where the wind is coming from. This process is excellent for the non-pilot but not for the current pilots. Weather has always been an area of aviation that causes the most crashes.

Studies have shown that most pilots' weather knowledge and knowledge of applying the data to the intended flight are dramatically deficient. In my forty years of flying and seventeen years as a flight instructor, I am learning new weather scenarios before every flight. The act of going onto an app one hour before a flight and knowing the winds, ceilings, and density altitude is simply not enough and is dangerous.

Based on FAA data, the top two leading causes of fatal GA accidents from 2001 through 2016 are loss of control–in–flight (LOC-I) and controlled flight into terrain (CFIT). Weather conditions can play a role in both LOC-I and CFIT. In addition, unintended flight into instrument meteorological conditions (IMC) is also on the FAA's list of top fatal GA accident types. By far, the most dangerous conditions occur when a flight conducted under visual flight rules continues into IMC. As noted in the 26th Joseph T. Nall Report, published by AOPA, "Almost 70 percent of all accidents in IMC were fatal, compared to 17 percent of those in visual meteorological conditions (VMC) during daylight hours and 26 percent of those in VMC at night," (AOPA Air Safety Institute. 26th Joseph T. Nall Report. 2017).

A genuinely enlightening study of weather knowledge came from Embry Riddle in 2021. The study is General Aviation Pilots' Capability to Interpret Aviation Weather Displays, JOURNAL OF AIR TRANSPORTATION; Vol. 29, No. 4, October–December 2021. Eight hundred and thirty-seven general aviation pilots completed an online aviation weather product interpretation test that asked pilots to apply information gleaned from weather hazard products for flight planning.

Certified private pilots scored significantly lower than certified commercial pilots, flight instructors, and airline transport pilots. Private pilots with instrument ratings scored considerably lower than certificated flight instructors and air transport pilots. Further analysis revealed that pilots scored lowest on ceiling visibility analysis, satellite, station plots, and surface prognostic products. The highest scores were associated with winds aloft, graphical turbulence, and pilot reports. The results have implications for both weather display design and pilot training. Before this study, previous aviation literature had indicated that a lack of weather knowledge and poor product interpretability may contribute to the high probability of fatalities in general aviation weather-related accidents. This study validated this premise.

I will share how I teach weather and my weather collection process before the flight. My aviation weather knowledge began at the age of ten (1962) as I watched a local weather person who was a pilot. The words, "For all of you VFR (visual flight rules) pilots out there, you can sleep in tomorrow." I went to the library to find out what VFR meant. I imagined all pilots in southeast Michigan must be tuning in to this weatherman for their flight forecast. I started my flight lessons in 1983. I learned all about weather symbols and weather from a textbook. I collected my weather data from a Flight Service Station at Detroit Metropolitan Airport. I requested the weather for my intended flight, and the FSS would print the METAR, TAF, cloud conditions, temperatures, winds aloft, and SIGMETS on a dot-matrix printer. I would study the weather and make my weather decisions with my flight instructor. I would practice calling Flight Service during the week. The forecast would often change depending on the time of flight. I carried my favorite weather book in my flight bag.

My student's first flight lesson includes a thirty-minute introduction to aviationweather.gov.

Aviationweather.gov is the NOAA National Weather Service (NWS) website. My other go-to weather service is 1-800-WX-BRIEF (Leidos Flight service) before each flight. The pilot initially sets up a new personal account, and subsequent weather briefings will be held with a professional weather briefer. All aviation accident investigations will research whether the pilot received weather information from the NWS website or used 1-800-WX-BRIEF. In the past years as an instructor, I have used NOAA Weather and supplemental information from WUNDERGROUND and the Weather Channel apps. I stopped that practice many years ago as the National Weather Service website has every bit of current and forecasted weather information that I need to make my flight as safe as possible.

My weather gathering process begins with looking at the PROG CHARTS. The Prognostic chart essentially means a weather forecast map that shows the predicted future weather conditions at a specific time, including details like pressure systems, fronts, precipitation, and wind patterns, allowing users to see how the weather is expected to evolve over a period of time. I recommend looking at the Prog Chart data four days out through the day of the flight. I will look at the graphical range wind/temperature chart forty-eight hours before the flight. This chart helps me know the forecasted wind speeds and directions at selected altitudes. In particular, I will look at the surface and three thousand feet winds. I can conclude if my student will have crosswinds for takeoffs and landings at the departure and destination airport, plus some general winds aloft information. In aviation weather, "TAF" stands for "Terminal Aerodrome Forecast," which is a coded message providing a detailed weather forecast for a specific airport and its immediate vicinity, outlining expected conditions like wind, visibility, clouds, and weather phenomena over a set period, usually 24 hours, allowing pilots to plan their operations accordingly. Twenty-four, up to two hours before the scheduled flight, I will check the TAFs at the closest airport to my destination airport at twenty-four, eighteen, twelve, and six hours before the flight. METAR stands for Meteorological Terminal Air Report, a concise, standardized report that summarizes the current weather conditions at an airport. I get up early, check the latest TAF, and monitor the METARS every hour before takeoff.

Following this process has worked well for me. I must admit that the forecast was often inaccurate, and the actual weather had changed. I remember on a cross-country flight, the winds aloft from a forecasted tailwind at three thousand feet to an actual direct headwind. My ground speed went from 110 knots to 45 knots. I had to refuel at the halfway point of the flight instead of having two hours of estimated fuel reserves at my destination airport. I recommend that all student pilots look at least three METARS/TAFS every other day for practice. There is an excellent chapter in the Airplane Flying Handbook published by the FAA on weather that is a must-read for all pilots. Have fun and fly well.

weather gathering for aviation

Larry M. Diamond, PharmD, CFII Larry Diamond has a Doctor of Pharmacy Degree and has been a pharmacist for 37 years. Larry’s pharmacy practice has been as a Clinical Pharmacy Specialist in Cardiology, Orthopedic Surgery Specialist and most recently Clinical Pharmacy Coordinator. You can find more articles by Dr. Larry Diamond on AOPA's website: https://www.aopa.org/news-and-media/articles-by-author/larry-diamond

Dr. Larry Diamond

Larry M. Diamond, PharmD, CFII Larry Diamond has a Doctor of Pharmacy Degree and has been a pharmacist for 37 years. Larry’s pharmacy practice has been as a Clinical Pharmacy Specialist in Cardiology, Orthopedic Surgery Specialist and most recently Clinical Pharmacy Coordinator. You can find more articles by Dr. Larry Diamond on AOPA's website: https://www.aopa.org/news-and-media/articles-by-author/larry-diamond

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