Millions of people were amazed last week by viral video footage of a Boeing 767 passenger jet landing at Britain’s Birmingham International Airport in terrifyingly windy conditions.
The 73-second video was uploaded to YouTube by user FlugSnug and has been viewed 6.7 million times so far. Here it is again:
We asked a pilot from the Royal Australian Air Force to explain what was happening to the jet as it made its landing approach, and also set out what the pilot was doing to put it on the tarmac.
In this case there is wind blowing from left to right as viewed in the footage.
There is significant “baseline” crosswind, with the occasional gust of crosswind higher than the baseline. Crosswind – wind that moves laterally across the airplane – pushes on the vertical tail like a large barn door.
As a result, the nose naturally yaws [twists] into the wind. This is a normal way to fly an aircraft, both in the cruise and in an approach to land.
Just prior to landing, the pilot “kicks” the aircraft straight by using rudder as required to align the fuselage [the body of the plane] – and, most importantly, the landing gear – with the runway.
Simultaneously, aileron [flaps on the wing used to control roll] will be required to prevent the aircraft from being blown off the runway centre-line.
All aircraft have a crosswind limit, partly due to rudder authority. Just like how the steering wheel in a car can only turn so far, the rudder has its limits.
It appears the crosswind must be around, if not above, this limit, meaning that the pilot cannot straighten the aircraft any further.
All aircraft are different and thus have differing limits. As a very rough figure, the crosswind component alone might be around 35 knots or 65km/h in this video, plus any associated head or tail wind adding to the total wind strength.
Also note that once on the runway, the plane weaves a little (the 0:36 and 0:41 mark), suggesting additional gusts beyond the baseline crosswind.
You’ll also notice a high rate of sink 2-3 seconds prior to touchdown (about the 0:27 mark), when the plane suddenly drops. This suggests a gust of tail wind hit, or the head wind has suddenly died down, reducing the amount of lift the wings were producing.
The contributes to the firm touchdown seen a moment later.
Most people who fly frequently will have experienced a landing similar to this, though perhaps not as dramatic. Next time your flight is twisting about on approach, you’ll know what’s going on.
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