Vincent, the blogger behind the Plastic Pilot blog, has written a short post where he noted how he was recently flying from Frankfurt to Madrid as an airline passenger when it was announced that his flight would be delayed by forty minutes due to “wind in Madrid.” Hence, Vincent checked the latest METAR for Madrid via www.easymetar.com and the reading indicated “34020KT WS R33L WS R33R” and then “340030KT WS ALL RWY” for the next update.
In other words, Madrid was experiencing wind shears – that is, an abrupt change in wind direction and speed over a (very) short distance. As Vincent noted, a typical wind shear starts with an increase of headwinds and updrafts and then it continues with tailwind and downdrafts. In other words, they are not something that you want to experience in an aircraft.
So just how dangerous are wind shears? Check out this video of a passenger plane battling wind shear in Hamburg:
However and to really appreciate wind shears and how they can quickly they can appear and impact a flight, check out this video showing the difference between a normal takeoff at Gatwick and then an abnormal takeoff with wind shear a short time later:
Finally, check out this extreme landing during a wind shear video of a Korean 747 at Hong Kong’s old Kai Tak airport that resulted in a few blown tires:
In other words and if passenger planes are being grounded or tossed around by wind shear, its probably best for you as a general aviation pilot to remain safely on the ground!
Actually, wind shear is a much larger hazard to airliners than it is to a small GA airplane. Why? Due to the airliners' much larger mass and inertia, they take a lot longer to regain their momentum after a sudden loss of headwind component. Small airplanes like the Cessna 182 I fly can regain their speed very quickly. I've flown through wind shear a few times in small airplanes – you just give yourself some extra airspeed prior to hitting the shear, and you'll get some light to moderate turbulence as you fly through the shear layer. Otherwise it's a non-event. Still worth approaching carefully with an instructor aboard your first time, and truly understanding the risks and mechanics of it though!
That's true but I've been caught by some nasty wind shear. One time at Rotterdam, I nearly lost control of the plane just coming over the threshold when the wind changed direction rapidly. A friend of mine wrote off a PA28R because of wind sheer when he ran out of lift crossing the threshold at another airfield and just dropped onto the boundary wall. He was okay but a nasty accident.