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93

Airplanes prefer to land in a headwind. This reduces their groundspeed compared to landing with the same tailwind. Braking distance grows quadratically compared to groundspeed. So any significant reduction in groundspeed is worth having. Successive airplanes should all come from the same direction to land. This removes any danger of collision when a plane ...


86

Extremely safe. Firstly, your pilots will have access to much more detailed and real-time weather information than you can get. They want to get home safely as much as you do, and will not fly if it is not safe to do so. If the wind is coming from straight ahead, there is no maximum limit, which is good as aircraft takeoff and land into the wind whenever ...


76

Yes, certainly! If your airspeed is lower than the speed of the headwind, the aircraft will fly backwards relative to the ground. Example videos: from ground (noisy, better turn down your volume) from cockpit However, note that headwind cannot cause a plane to fly backwards through the surrounding air. Constant wind does not affect airspeed.


44

To the first part of your question, the airplane is not moving BECAUSE his yoke movements are "strong and fast". Experienced pilots can feel a gust and respond with a control input to counter it before it has enough time to affect the aircraft. (You really can't appreciate this from a camera fixed to the airframe.) As mentioned in a comment, this ...


39

The general rule is: If you read it, it's true. If you hear it, it's magnetic. All charts and textual sources (METAR, TAF, winds aloft, surface analysis charts, etc) use true north as the reference. ATIS/AWOS/ASOS broadcasts, or any information a controller gives you over the radio, is magnetic. Wind direction broadcast over FAA radios is in reference ...


39

Short version: yes, the plane can take it The 737 — or any other plane — will not take off unless the wind is within safe limits for the aircraft type. Long version: your question almost answered itself Did you know that last year there was not even not one single airfare-paying passenger fatality? Keep this in mind for a while... Now, you came here ...


38

Ultrasonic anemometers are replacing the traditional cup anemometers in automated weather stations. The sensor measures the time it takes for an ultrasonic pulse to travel between the probes, which is affected by wind speed. In your second image, the object directly above the lights appears to be an anemometer. Source Ultrasonic sensors have the advantage ...


33

As a Virtual Controller on vatsim.net at Toronto, I can tell you the following: Depends on runways, most of the time they operate runways 24R and 23, which lands planes facing south west. Runways are chosen from the wind direction, as planes preferably land into the wind. Winds at Toronto just most likely will favor the 24 runways. The STAR(s) "Standard ...


28

Your airspeed does not remain constant because of inertia: it takes more time for the airplane to adapt to the new relative wind, compared to the time it takes for the wind to change. Example One: you're flying 80 knots and the headwind is 20 knots. Over a time of 3 minutes, the headwind gradually reduces from 20 knots to 10 knots. Since the change is ...


27

As far as METARs are considered, the wind direction gives the direction from which the wind is coming. From METAR definitions: Wind Direction. The direction, in tens of degrees, from which the wind is blowing with reference to true north. So, Wind 270 shows that the wind is coming from west. The reporting in ATIS and tower is the same, only difference ...


26

Assuming 'I just' means today 17 Oct UTC time, then American Airlines 2539 arrived at 22:52 local, or 2:52 UTC. Reported METAR at that time: KBOS 170254Z 32013KT 10SM SCT060 08/01 A3015 RMK AO2 SLP209 T00780011 51027 The winds being 320/13 and runways 22L/R facing heading 215, that means the tailwind component was 3 knots. Well within the 737-800 limitation ...


26

Jet stream is a stream of air flowing around the Earth from West to East at high altitude. With wind speed averaging more than 100+ km/h, it has a tremendous effect on a plane's ground speed. The pattern, strength and location of the stream is constantly changing. For example, during the (Northern Hemisphere) winter the stream generally strengthens, and ...


25

The device used to measure wind speed is called an anemometer. The one that spins with 3 spoon-like arms is just one type. There are some that have a propeller or fan that spins like a windmill. There are other types that aren't so obvious, such as the ultrasonic anemometer that has no moving parts, but instead uses ultrasonic sound waves to measure wind ...


24

Normally not: Extracting energy from the airflow produces drag, which must be overcome by added thrust. Since every form of energy conversion produces losses, more thrust energy must be added than can be gained from the airflow. Only when the engines fail and the generators stop running does it make sense to extract energy from the airflow. In airplanes ...


24

When dealing with crosswinds and drift, I find the easiest way to understand the concept is to imagine a fast flowing river of water. If you tried to swim straight across a fast river you will end up downstream. You don't "feel" the current. You just keep swimming and the current carries you. Any time you have wind it is like a river of air flowing over ...


23

It's perfectly legal, but check the Chart Supplement (or AFD, or instrument approaches) to see if there are special exceptions for that airport. If it is a non-towered airport and you aren't assigned a runway, you should of course try to use the prevailing runway that is already in use by other traffic in the pattern when it makes sense. Some airports have ...


23

Yes, I have done this many times in hang gliders, and at least once in a Cessna 152. In the latter case, the wind aloft was much stronger than at the ground-- it would be foolish to take off or even taxi in a ground-level wind strong enough to fly a light plane backwards. You may enjoy this video of flight at zero groundspeed (I am not the pilot!) -- ...


22

Given how few bounding criteria you have in your question, the general result is For fixed wing aircraft: your ground speed will be significantly higher than if you'd taken off heading into the same wind, and thus you'll tend to use up more runway before lifting off. Example: with a take off speed of 100 kts, going into or downwind is the difference ...


22

Why pilot make so much input,I dont see that plane is moving even his yoke movements are huge and fast? The plane isn’t moving much because as soon as the pilot senses either wing lifting, he is making a correction to counteract it. Since he is flying in a gusty crosswind, that means many such corrections are required to keep the plane stable. For person ...


21

Some comments state this was a wind-shear, is that correct? Looking at the windsock which appears in the right bottom corner at 0:12 and remains visible for about 4 seconds, you can tell there is little wind, not what you would associate with wind shear. I want to ask here, what caused this very bumpy landing? It is always hard to judge the actions of ...


21

The easiest way to tell the direction of the wind when you're near the water is to look for something on the shore that indicated wind direction (beaches often have flags on them) Barring that there are a bunch of other clues that should be familiar to any sailor (or seaplane pilot) which you can borrow: Boats lying at anchor weathervane and automatically ...


21

Yes, the effect is there, and (auto-) pilots have to compensate for it, but the direct impact of the Coriolis force is insignificant compared to the impact of any wind forces. This has been discussed on Physics SE: Coriolis force on bullet vs airplane On the other hand side, the Coriolis force (seemingly) deflects moving air masses and causes the global ...


20

This might take a few seconds longer, but it's math-free: On your kneeboard, draw a quadrant (like this: +). Draw a line through it for your runway(s). Draw an arrow to represent the wind. The answer will be apparent. Do it enough times, and you'll be able to visualize the drawing without actually doing it. It's also a great technique for calculating holds.


20

My answer was rather concise first, and I got the impression that I need to elaborate the question first. The question is about the best airspeed for maximum range. With wind. Best range means you cover the most distance while the wind is carrying the plane with it. If you have a headwind, the longer you stay aloft, the more you are carried back, so you ...


19

As you can see on google maps Gatwick's runways are aligned (like many in the UK due to our prevailing winds) roughly east-west. In actual fact the runways are numbered 08 & 26 relating to 080 and 260 degrees respectively. A wind coming from the SSW, for arguments sake, blow at roughly 200 degrees. Aircraft take off into wind, so you will invariably ...


19

Been there, done that. A poorly forecast cold front once had me flying backwards in a Cessna 172 over Altoona, IFR (instrument flight rules) at night. Center asked me several times to verify my heading. Then when it was clear to them, they asked me my intentions. I told them I had lots of fuel and could continue to wait things out for an hour or so. The ...


19

As already said in the other answers, the "huge" inputs to the yoke are to keep the aircraft stable on the approach path. There is no "panic" involved, it is simply necessary due to the gusty conditions. Let me expand a bit more on your second question: Can airliners land with auto pilot on strong windy day [...]? The answer to this a ...


18

It's not so much a matter of "pilots typically get very uncomfortable" as it is "pilots recognize that it is an inherently less safe situation", and pilots (at least the ones you want to fly with) tend to be somewhat safety obsessed. So Why are tailwinds during landing "bad"? The same reason tailwinds in cruise flight are good: you're moving over the ground ...


18

High windspeeds themselves are not a problem, but the environment surrounding them may be. For example, in the wintertime it is not uncommon to find a strong core of fast winds embedded within the polar jetstream. We term this windspeed maximum a 'jet streak'. There are a couple of meteorological phenomena associated around these jetstreaks, such as ...


18

It's not too logistically complicated on its own. You just stop takeoffs, start taxiing the conga line of waiting airplanes to the new runway, let airplanes currently on final land, and start vectoring the other airborne flights toward the new approaches once the last of takeoff traffic is away. Once the new landing flow is established, start releasing the ...


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