Spring Weather


April 2017

Spring is here, and you’re ready to take to the skies. But are you, really? Before you start another season of dawn patrol breakfast runs, weekend trips to the beach or the mountains and touch-and-goes as the sky goes red with dusk, you’d better get a little dual and knock the rust off your flying skills—because before summer comes you’ve got to get through the weather of spring.

You’ll enjoy some of the nicest flying weather of the year in spring, with clear, cool skies. But the contrast between warm and cold weather also hits you with some of the worst of flying weather.

Cold fronts roaring down from the Arctic create the instability that feeds springtime severe storms. Fast-moving warm fronts spawn embedded thunderstorms, hidden in low clouds. In spring it’s not unusual for two or even three fronts to blow past each week. So there’s a lot of exposure to fast-growing thunderstorms as you return to the skies in spring.

How can you detect and avoid the thunderstorm threat? Widespread access to weather radar, during preflight planning and often using weather uplinks while in flight, has made thunderstorm avoidance much easier that it was in the past. Recall, though, that storms build rapidly and can contain dangerous turbulence in the cumulus, or formative stage—by definition before rain falls, so before the storm is painted on radar. Check the live feed, but also heed Convective SIGMETs, the Convective Outlook and other forecast products. Look at the times involved—forecast periods for outlooks, radar update times (the “latency period”) on live uplinks. It’s best to use visual avoidance when storms threaten your flight.

Fog and Low Clouds 
Wet air gets cool, and fog and low clouds form. This is common on clear, cool nights, which are abundant in spring. Anticipate, even expect, obscured visibility from just after sundown to well past sunrise. To avoid the threat of fog and low clouds, watch the temperature/dew point spreads (within a few degrees usually means a restriction to visibility), and if the air is moist, wait until a little while after sunrise to see if fog or low clouds are forming before you fly.

Spring may seem warm enough, but in most parts of the country it’s still cold enough for ice. Stay out of clouds and visible moisture if the temperature is near or below freezing. Always plan an escape route in case you unexpectedly encounter ice, even in a “known ice” airplane. Watch for RPM or manifold pressure loss in carbureted engines, even if the skies are clear, because spring temperatures are prime for power-robbing carb ice.

Avoid ice by avoiding flight in clouds or visible moisture at altitudes where the air is near or below freezing. The FAA’s Current Icing Product and Forecast Icing Product charts, available at www.aviationweather.gov and through most flight planning software, are superb indicators of the icing threat.

I can handle crosswinds! That’s what everyone thinks. Then why do crosswind accidents cost the industry millions of dollars each year? Pilots don’t often consider wind to be a weather hazard, but rather something to be overcome. In spring’s winds, pilots are often wrong.

To avoid the strongest surface winds, check the METARs and TAFs. Pilots often compute the crosswind component to decide whether to take off, but you must also compute the crosswind component (using AWOS, ASOS or ATIS, or visual cues) to decide whether you should attempt to land on your selected runway…of if you need to go somewhere else.

Spring is the season of weather hazards. Often spring is the same time pilots’ recent flying experience is at its lowest. Get a good flight review and some practice to start the flying season. Then watch weather conditions closely, and don’t try to handle too much before you’re back up to speed for the flying season.

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Holder of an ATP certificate with instructor, CFII and MEI ratings and a Masters Degree in Aviation Safety, 2010 National FAA Safety Team Representative of the Year, 2015 Inductee into the NAFI Hall of Fame and 2008 FAA Central Region CFI of the Year, three-time Master CFI Thomas P. Turner has been Lead Instructor for Bonanza pilot training program at the Beechcraft factory; production test pilot for engine modifications; aviation insurance underwriter; corporate pilot and safety expert; Captain in the United States Air Force; and contract course developer for Embry-Riddle Aeronautical University. He now directs the education and safety arm of a 9000-member pilots’ organization. With over 4300 hours logged, including more than 2600 as an instructor, Tom writes, lectures and instructs extensively from his home at THE AIR CAPITAL--Wichita, Kansas. Subscribe to Tom’s free FLYING LESSONS Weekly e-newsletter at http://mastery-flight-training.com/

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