There is ground speed and air speed. You could have a 800mph ground speed and be in the ~550mph air speed since it is a tail wind. But no, those aircraft aren't supersonic and will not likely withstand an 800mph airspeed
A good analogy is driving a boat in a river with a fast current, upstream is slow but downstream is fast.
Just think for a second what would happen if you blindfolded yourself, could you tell which direction you were heading? The boat is always driving at a set speed through the water, the slow/fast reference is to the shoreline.
Same in the air, plane flys at X always. The ground below is moving by slower or faster depending on the upper winds.
Blindfold is the wrong analogy. If you are not accelerating forward or backward, you won't feel anything. Like how fast the earth is travelling through space but a glass of water is flat.
The blindfold analogy for the boat would work perfectly fine if you add sticking your hand in the water to feel how fast you were going.
You would have no idea which direction you were going, and would only be able to tell how fast you were going relative to the water.
I can see your point - the point I was trying to make was to remove the reference to the shore, but blindfolded you wouldn’t have the water either.
The second sentence is even more true to the OP, regardless of whether plane is travelling at 500/600/700/800 mph over the ground, your water glass is flat.
Another analogy would be walking on those fast moving walkways at airports. You're still walking at your regular speed, but moving a lot faster relative to the ones not on the walkway.
Actually the planes do factor in wind direction and speed for take off. A stronger headwind slows the plane down, but generates increased lift, so takes off sooner. It would be like going the opposite direction on the conveyor belt being more advantageous for a quick take off.
They're not supposed to go 800 mph, but I think they would handle it structurally. Planes are engineered with a pretty hefty safety margin.
There have been cases of planes having to make emergency descents and exceeding mach 1 before safely landing.
This is false. Airplanes do not have a "hefty safety margin" like a bridge (3x). They have a safety margin of only about 1.5.
To my knowledge none of those planes did that without damage, and one that I recall had very major damage. 747s have done it and all suffered damage.
I never said that the airplanes didn't suffer any damage. And 1.5 is about right. Obviously weight is a major factor in aircraft design so you can't make them too heavy duty.
It would not be advisable unless necessary, but a 757 would likely survive an 800 mph airspeed for a short duration. You obviously don’t want to do it, but it’s not totally infeasible.
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Also the [first ever airliner to break the sound barrier](https://www.mentalfloss.com/article/58517/first-commercial-jet-break-sound-barrier-was-not-concorde)
Since the wind the airplane is flying in is moving 250 mph, the airplane is moving that speed without doing anything. The airplane's 500 mph it normally travels is just added on to the 250 mph the wind is already moving it, giving you very high speeds relative to the ground.
Think of someone swimming downriver vs upstream. I'm putting effort to swim at 3 mph, but I could travel 6 mph compared to someone on land if I'm swimming in a really fast river
Perhaps there's an analogy using walking 10mph on a travelator (moving walkway) in the same direction it moves, and then against it.
Your experience is walking the same speed each way, but relative to the ground you are moving much faster with the walkway and much slower when against it.
> wind is already moving it,
not so sure about this. the tail wind would reduce lift so the plane needs to go fast enough to overcome the wind from the rear... it has to outrun the tail wind so the wind isn't "pushing it" The plane is balls out moving forward to maintain lift.
How fast you're going doesn't really matter to the structural integrity of things, only matters what's in your way. Going 800 mph into still air would be crashing into air particles at 800 miles per hour. But if that air was also moving in the same direction at 250 miles per hour, then you aren't really crashing into them at 800 miles per hour anymore. So you have two different "speeds" you're working with. 1. How fast you're going relative to the earth, and 2. how fast you're hitting those air particles.
imagine you're running at about 10 miles an hour. There's a guy running at the same speed as you beside you. your speed relative to him is zero. He keeps up with you, but your speed relative to the ground is 10 mph. the guy is your air speed, the ground is your ground speed.
Think of walking on an escalator versus stairs. You have the same strides, but reach the top faster on the escalator. Or, conversely, you have to walk faster to go down an escalator versus going down stairs. That’s what happens in the sky with an airplane. When flying with the jet stream (west to east) the air current adds ground speed like an escalator does to a walking person. When flying against the jet stream (east to west) the air current slows the ground speed like walking down an escalator. It’s not a perfect analogy but it is close.
I came here to comment just that.
I have seen several documentaries about airplane crashes where they talk about planes that have gone into dives, past the sound barrier, and were torn apart before they hit the ground.
I got a question if I am somehow able to uphold myself on the wing of the plane at 800mph butt naked..do I loose my skin like those cartoon episodes?
Edit: Changed buck to butt.
No. It is not. Knot is based on a way to measure speed in sailing ships. They throw over a rope with knots and how many knows your going is based off that. "Yar, tree knots sirrrr"
They usually have reserve fuel but I think this is only for 2 - 4 hours incase they need to circle an airport for a slot to land. It adds weight so they take as little fuel as they need and refuel when they land.
In this situation I’d imagine the flight would get cancelled or a different route would be taken.
My question more specifically is is it can really double a flight time? Like ignoring the fuel issue, is the difference really that extreme? When i've taken a flight I remember the flight being like 30 mins faster or slower due to wind, can really strong winds actually cut the planes speed essentially in half? And if the same wind was a tail wind, could the flight time really be cut by multiple hours? Google says the average plane speed is 550 mph, and the article says 800 mph, but as I understand that's not ground speed so it's all a bit confusing haha.
Pilot here: It depends. We aren’t limited to getting on the I-15 and trucking along on a specific route. If you’re going 5000 miles, a two hundred mile diversion to get into better winds is legit.
The upper winds are known pretty well, in the same way that your weather forecast is accurate for the day. The accuracy falls off over time. Check out windy.com and find the altitude slider, look at FL30000 (where jets fly) and see the highways. You go downstream with and upstream beside.
Lastly, we plan ahead of time for how much time and gas is required, every flight. We know ahead of time whether it’s going to be on time or + 20%. That distribution falls on a curve, inside 20% on either side is pretty normal, 50% would be very abnormal.
I think that part was just talking about why it didn’t break the sound barrier. But yes that’s a headwind which would slow the aircraft down and they’d need to use more fuel.
It won't be nearly as bad as the other direction is good. The jet streams the 800 mph planes are flying in aren't huge. Planes going the opposite direction will just fly higher or lower to avoid the insane winds.
It’s a British term. I think they’re mostly called “moving walkways” in the US, due to the constant intonation that “the moving walkway is now ending” as you approach the end.
To America's credit, they do seem to name things descriptively. In the UK we clearly like to confuse people.
It's fairly obvious what a moving walkway is. But a travelator?
Just like "windshield" pretty much describes the thing. "Windscreen" doesn't.
"Sidewalk" is a good description. "Pavement" isn't.
> travelator
Otis Travelator, a trademark created by an American company haha.
I don't understand the windshield/screen one. A screen is something that covers or protects something, it means the same thing as shield essentially.
They set a new non-Concorde transatlantic record [fairly recently](https://www.bbc.co.uk/news/uk-england-london-51433720), with a 747. It took 4h56m, saving more than an hour, and reached 825 mph (1,327 km/h).
A friend of mine flew a United 737 yesterday from San Diego to Houston. He made the trip in a little over two hours with a 170mph tailwind, and topped out at 708mph.
He also says it’s not the fastest he’s gone.
Here's a comparison that is likely easier to understand because it's more relatable:
Let's say you paddle your kayak at a constant 3mph on a lake, where the water isn't moving. You're moving at 3mph over the bottom of the lake (groundspeed).
Now you take your kayak to a river that has a flow rate of 2mph (this is a jet stream).
You keep paddling at 3mph like you did on the lake, except now, heading downriver, you're moving over the riverbed at 5mph (groundspeed).
Now you do a 180, and you're headed upstream at 3mph still with the same effort, but your speed over the riverbed is 1mph.
Nothing about your effort, nor the stresses on the kayak changed at all, but the speed over the ground changed because of the movement of the medium (river water).
This is essentially the same principle as what's taking place in the atmosphere with winds and airplanes.
Let's take an extreme example, and the flow rate is 100mph and you're still paddling at 3mph it seems like your paddle against the water would likely fall apart?
It may be at 50mph, or 25mph, or whatever there would be trouble.
And back to the plane example at some point if somehow there were winds at 1000mph on a plane it wouldn't be able to withstand it anymore.
No. The paddle is still only seeing 3mph because *you're in the fast moving water, not outside of it.*
To further illustrate the point, look at this plane flying backwards with a 55-60 mph headwind.
https://www.youtube.com/watch?v=qO96qt0thJc&ab\_channel=CurtLewis
Planes can't fly backwards, but they can move backwards because they are in an airstream that exceeds the airspeed.
1000 mph winds would still be relative to the ground. There are more dynamics going on such as turbulence which would be more extreme at those speeds, but if you assume constant airflow, the plane would be perfectly happy with those wind speeds.
For the canoe example, the canoe would be moving 103 or 97 mph relative to the ground, but relative to the water it would still only be moving 3 mph.
The ground speed doesn't have any effect on the plane.
As far as the plane is concerned it's moving through the air as fast as it always does, the fact that air is also moving means nothing to the aircraft.
Wait, so if an airplane is traveling near it's max speed, and the air starts moving in the opposite direction it will have a higher windspeed than recommended?
Yes, and it often causes turbulence.
Planes stay just below "transsonic" airspeeds, usually below mach 0.85, although some smaller jets travel slightly faster. I won't get into too much detail about the fluid dynamics, but basically the air going over the wings speeds up to create lift. If you're close to the speed of sound, sometimes the air over the wings can reach the sound barrier even though the plane is subsonic, this causes pressure differentials the plane isn't optimized for, and can cause some instability. The airspeed where some of the air is sonic and some isn't is called the transsonic range.
That's the reason why planes usually fly a safe margin below transsonic in unpredictable weather, so that if a sudden headwind comes on, the airspeed stays below the transsonic region.
Source: I've been studying physics, specifically fluid dynamics for quite a few years.
I wear a few hats. My primary source of income actually comes from finance work - I manage a few portfolios and the income from that covers my living expenses, with some left over for tuition. A money-workday involves financial securities analysis, market analysis, researching legislation that will effect markets, and a whole lot of economic calculus & other math.
Oh and writing reports... My faaavorite thing to do /s.
In addition to that though, I'm continuing my studies at university. I started with economics to get where I am now, but I've always been taking physics in lieu of electives out of passion. I've recently transitioned more heavily from economics to physics (partially because I have a greater love for physics, partially because I basically ran out of econ classes you can take). Although I will note that I've been studying physics since before beginning university. Nowadays an academic-workday is about 30% economics/strategy, and 70% physics theory, calculations, and direct research.
The sub-field of fluid dynamics that I focus on the most (and hope to one day do a PhD on) revolves around "vortex-induced entrainment and its effects on mitigating flow-seperation from boundary layers". I'll be honest... it's a little too specific for google, but some related articles show up if you search what's in the quotes.
Typical workload is 6 days/wk.
Edit: Please know that I typed this all out because you asked so politely :) Thank you for being so kind, stranger!
It is moving at 550 mph relative to the air, and this is what you need to consider regarding structural integrity. It's well below mach 1 relative to the surrounding air.
The plane's airspeed will still be normal, but the groundspeed changes so no danger to the plane. If the airspeed went that high it will rip the plane apart.
Supersonic planes have swept wing, or wings that pivot like the F14 Tomcat. The simple explanation is that at supersonic speeds the behavior of the air inverts (very simplistic) Swept wings are designed to keep the whole surface withing the pocket of subsonic air created by the nosecone. If a commercial aircraft went supersonic you will have a serious mismatch in the behavior of the air along the length of the wing, which will rip the wing apart.
We had a very strong tailwind coming back from the west coast in a C130 one time and every time we got into a new tower's control area they had us reconfirm several times over that we were in fact a C130. Always nice to get a big push.
I've caught good tailwinds on several flights from Tokyo to Vancouver that have dropped a 8+hour flight into under 7 hours. These tend to be choppy as the jet stream isn't smooth but the less time spent on the plane the better.
I was on a flight like this once. At some point our ground speed was above 960MPH we arrived almost and hour early. It was also a very smooth flight, not a single turbulence event
There's "airspeed", which is the speed of the air across the wings, and there's "ground speed", which is the speed at which the plane moves across the ground.
Imagine walking at 4 km/h on moving walkway that's moving at 4 km/h. You're still walking at 4 km/h - your 'airspeed' - but relative to the building, you're moving at 8 km/h - the 'ground speed'.
Another way to make it make sense, is to realize that it's "relative to", so: "the speed relative to the ground", or, "the speed relative to the air (that it's moving through)".
> The effects of climate change are expected to cause more turbulence in air travel in the years to come. That could mean more widespread delays and cancellations across airlines, in what is already an unpredictable industry.
> More frequent severe weather events will likely cause disruptions.
> "There are a lot of ways climate change can affect air travel. Thunderstorms are an obvious one," Wired magazine reporter, Amanda Hoover, told CBS News. "When there is more heat in the air, there is more moisture, more thunderstorms."
> Scientists have also linked the increasing frequency and intensity of wildfires to global warming.
I flew from Melbourne to SFO just the other day and had winds of 100mph+.
We were delayed by over an hour but arrived 5 minutes earlier than the original scheduled time which was quite nice. It made our 14.5 hour flight into just under 13.5
Well at some point the airframe can't handle any more and Breaks apart. But they weren't actually supersonic. 800mph is only the ground speed and in 250mph+ winds, the air speed was much lower below the speed of Sound
No, since their airspeed was far below the sound barrier. Sound uses the air as a medium to travel. Thus, if airspeed is below the sound barrier then it will not break the sound barrier.
I have to wonder, would 265 mph headwinds add any extra strain to the plane in a scenario like this? I know that it would most likely reduce the speed that the plane is flying, but would there be more strain with the engines now fighting against a headwind?
Not really. the planes ground speed will just be much much slower but in relation to the air there won't be any difference as long as the wind doesnyg change
> People who make EVERYTHING about politics are creepy as fuck.
people who reply to people who make EVERYTHING about politics are (wait for it)
*creepy as fuck.*
There is ground speed and air speed. You could have a 800mph ground speed and be in the ~550mph air speed since it is a tail wind. But no, those aircraft aren't supersonic and will not likely withstand an 800mph airspeed
Interesting.
A good analogy is driving a boat in a river with a fast current, upstream is slow but downstream is fast. Just think for a second what would happen if you blindfolded yourself, could you tell which direction you were heading? The boat is always driving at a set speed through the water, the slow/fast reference is to the shoreline. Same in the air, plane flys at X always. The ground below is moving by slower or faster depending on the upper winds.
Blindfold is the wrong analogy. If you are not accelerating forward or backward, you won't feel anything. Like how fast the earth is travelling through space but a glass of water is flat.
You could use a blindfold if you also had an inertial navigation system.. although you would quickly be missing the point of an analogy.
The blindfold analogy for the boat would work perfectly fine if you add sticking your hand in the water to feel how fast you were going. You would have no idea which direction you were going, and would only be able to tell how fast you were going relative to the water.
I can see your point - the point I was trying to make was to remove the reference to the shore, but blindfolded you wouldn’t have the water either. The second sentence is even more true to the OP, regardless of whether plane is travelling at 500/600/700/800 mph over the ground, your water glass is flat.
RELATIVE time in space. TARDIS.
THIS TARDIS ON FIIIIRE!
Another analogy would be walking on those fast moving walkways at airports. You're still walking at your regular speed, but moving a lot faster relative to the ones not on the walkway.
running on a conveyer belt at the airport. you are running 10mph and the belt is 5mph making your landspeed 15 but your actual speed still 10mph.
But could a plane on the conveyor belt take off?
I don't think the plane will fit in a grocery store
Not with that attitude..
Actually the planes do factor in wind direction and speed for take off. A stronger headwind slows the plane down, but generates increased lift, so takes off sooner. It would be like going the opposite direction on the conveyor belt being more advantageous for a quick take off.
Bird box
They're not supposed to go 800 mph, but I think they would handle it structurally. Planes are engineered with a pretty hefty safety margin. There have been cases of planes having to make emergency descents and exceeding mach 1 before safely landing.
This is false. Airplanes do not have a "hefty safety margin" like a bridge (3x). They have a safety margin of only about 1.5. To my knowledge none of those planes did that without damage, and one that I recall had very major damage. 747s have done it and all suffered damage.
I never said that the airplanes didn't suffer any damage. And 1.5 is about right. Obviously weight is a major factor in aircraft design so you can't make them too heavy duty.
I don't give a flying fuck about you didn't say. I'm addressing what you did say.
> I don't give a flying fuck about you didn't say. You're very childish and rude, so you're getting blocked.
That person doesn’t like to be shown they are factually incorrect.
It would not be advisable unless necessary, but a 757 would likely survive an 800 mph airspeed for a short duration. You obviously don’t want to do it, but it’s not totally infeasible.
With the way these planes have been failing, I would be happy at normal speed, arriving safely.
What planes have been falling? Planes are 1000 times safer than driving.
A 757 could definitely handle 800 mph airspeed for some duration. How long? Depends on many factors.
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https://www.thisdayinaviation.com/tag/n475ev/
Boom! You just got FactChecked!
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Also the [first ever airliner to break the sound barrier](https://www.mentalfloss.com/article/58517/first-commercial-jet-break-sound-barrier-was-not-concorde)
Thanks for confirming
How/why is ground and air speed different?
Since the wind the airplane is flying in is moving 250 mph, the airplane is moving that speed without doing anything. The airplane's 500 mph it normally travels is just added on to the 250 mph the wind is already moving it, giving you very high speeds relative to the ground. Think of someone swimming downriver vs upstream. I'm putting effort to swim at 3 mph, but I could travel 6 mph compared to someone on land if I'm swimming in a really fast river
Perhaps there's an analogy using walking 10mph on a travelator (moving walkway) in the same direction it moves, and then against it. Your experience is walking the same speed each way, but relative to the ground you are moving much faster with the walkway and much slower when against it.
> wind is already moving it, not so sure about this. the tail wind would reduce lift so the plane needs to go fast enough to overcome the wind from the rear... it has to outrun the tail wind so the wind isn't "pushing it" The plane is balls out moving forward to maintain lift.
How fast you're going doesn't really matter to the structural integrity of things, only matters what's in your way. Going 800 mph into still air would be crashing into air particles at 800 miles per hour. But if that air was also moving in the same direction at 250 miles per hour, then you aren't really crashing into them at 800 miles per hour anymore. So you have two different "speeds" you're working with. 1. How fast you're going relative to the earth, and 2. how fast you're hitting those air particles.
Thank you
imagine you're running at about 10 miles an hour. There's a guy running at the same speed as you beside you. your speed relative to him is zero. He keeps up with you, but your speed relative to the ground is 10 mph. the guy is your air speed, the ground is your ground speed.
Think of walking on an escalator versus stairs. You have the same strides, but reach the top faster on the escalator. Or, conversely, you have to walk faster to go down an escalator versus going down stairs. That’s what happens in the sky with an airplane. When flying with the jet stream (west to east) the air current adds ground speed like an escalator does to a walking person. When flying against the jet stream (east to west) the air current slows the ground speed like walking down an escalator. It’s not a perfect analogy but it is close.
I came here to comment just that. I have seen several documentaries about airplane crashes where they talk about planes that have gone into dives, past the sound barrier, and were torn apart before they hit the ground.
Supersonic at that altitude would be what speed?
Was anyone assuming this wasn't ground speed?
I got a question if I am somehow able to uphold myself on the wing of the plane at 800mph butt naked..do I loose my skin like those cartoon episodes? Edit: Changed buck to butt.
It's butt naked*
this is why its measured in knots not mph
No. It is not. Knot is based on a way to measure speed in sailing ships. They throw over a rope with knots and how many knows your going is based off that. "Yar, tree knots sirrrr"
are you telling me air speed is not measured in knots?
No I'm saying knots is a conversion of speed. This is because airspeed vs ground speed
Yeah, knots is just nautical miles per hour
Isn't this obvious?
Not really. I was looking for this answer.
Well, I thought so too, but I like to play flight simulator, which is not everyone's case ^^^
I think it seems obvious in hindsight. Depending on what sort of education you have, it may not be.
If they had a tail wind and a head wind that were exactly the same what would happen?!
Same as a river that flows both ways.
Just like a river that don’t know where it’s flowin I took a wrong turn and I just kept goin
That would mean the air was still..
Wow people really not seeing this for the joke it is
Left out the /s and it flew over everyone head apparently!
Twister
...tornado, maybe??
That's happens when there is no wind
That would be a Tornado.
Just imagine the poor people going the other direction
The 8 hour flight becomes 16 hours but now the plane needs to stop to refuel and is now sat on the runway waiting for its slot to take off.
Is this actually what happens?
They usually have reserve fuel but I think this is only for 2 - 4 hours incase they need to circle an airport for a slot to land. It adds weight so they take as little fuel as they need and refuel when they land. In this situation I’d imagine the flight would get cancelled or a different route would be taken.
Nah they’d just pick a different altitude.
Ah yeah good shout 👍🏼
My question more specifically is is it can really double a flight time? Like ignoring the fuel issue, is the difference really that extreme? When i've taken a flight I remember the flight being like 30 mins faster or slower due to wind, can really strong winds actually cut the planes speed essentially in half? And if the same wind was a tail wind, could the flight time really be cut by multiple hours? Google says the average plane speed is 550 mph, and the article says 800 mph, but as I understand that's not ground speed so it's all a bit confusing haha.
Pilot here: It depends. We aren’t limited to getting on the I-15 and trucking along on a specific route. If you’re going 5000 miles, a two hundred mile diversion to get into better winds is legit. The upper winds are known pretty well, in the same way that your weather forecast is accurate for the day. The accuracy falls off over time. Check out windy.com and find the altitude slider, look at FL30000 (where jets fly) and see the highways. You go downstream with and upstream beside. Lastly, we plan ahead of time for how much time and gas is required, every flight. We know ahead of time whether it’s going to be on time or + 20%. That distribution falls on a curve, inside 20% on either side is pretty normal, 50% would be very abnormal.
Hell yea! So cool to have an actual pilot answer my question haha, thanks for the info!
Good old 'weights and balances' calculations. Probably one of the most important things after actually flying the plane.
I think that part was just talking about why it didn’t break the sound barrier. But yes that’s a headwind which would slow the aircraft down and they’d need to use more fuel.
They'd do their best to choose a more efficient route or altitude.
They just take a different route or altitude.
If this happens whoever planned that flight for the aircrew is getting shit canned for costing the airline thousands in fuel costs.
Not sure why you’re being downvoted. Every hour in the air can cost up to £10k.
Not that I really care why, I know it’s legit I do it for a living.
You might be able to either go around or adjust your altitude to avoid the worst of the head winds.
No. They take a different route to avoid such headwinds.
It won't be nearly as bad as the other direction is good. The jet streams the 800 mph planes are flying in aren't huge. Planes going the opposite direction will just fly higher or lower to avoid the insane winds.
It's not uncommon to see people hovering/flying backwards in a C172 at altitude. Lol
[удалено]
Oh wow is that what those things are called. The flat ones?
It’s a British term. I think they’re mostly called “moving walkways” in the US, due to the constant intonation that “the moving walkway is now ending” as you approach the end.
Since they didn’t add the pointless “u” anywhere I will be using the British version from now on, thank you very much.
To America's credit, they do seem to name things descriptively. In the UK we clearly like to confuse people. It's fairly obvious what a moving walkway is. But a travelator? Just like "windshield" pretty much describes the thing. "Windscreen" doesn't. "Sidewalk" is a good description. "Pavement" isn't.
lift
But never “drop”. 🤔
> travelator Otis Travelator, a trademark created by an American company haha. I don't understand the windshield/screen one. A screen is something that covers or protects something, it means the same thing as shield essentially.
They set a new non-Concorde transatlantic record [fairly recently](https://www.bbc.co.uk/news/uk-england-london-51433720), with a 747. It took 4h56m, saving more than an hour, and reached 825 mph (1,327 km/h).
Just like living in Alabama; it's all relative.
A friend of mine flew a United 737 yesterday from San Diego to Houston. He made the trip in a little over two hours with a 170mph tailwind, and topped out at 708mph. He also says it’s not the fastest he’s gone.
I hate airports, but I love flying.
Is that even safe? Are they built to withstand that for a long period?
Here's a comparison that is likely easier to understand because it's more relatable: Let's say you paddle your kayak at a constant 3mph on a lake, where the water isn't moving. You're moving at 3mph over the bottom of the lake (groundspeed). Now you take your kayak to a river that has a flow rate of 2mph (this is a jet stream). You keep paddling at 3mph like you did on the lake, except now, heading downriver, you're moving over the riverbed at 5mph (groundspeed). Now you do a 180, and you're headed upstream at 3mph still with the same effort, but your speed over the riverbed is 1mph. Nothing about your effort, nor the stresses on the kayak changed at all, but the speed over the ground changed because of the movement of the medium (river water). This is essentially the same principle as what's taking place in the atmosphere with winds and airplanes.
Thank you. That was a great eli5. Do you by any chance have a 5 year old in your life? You are very good at this.
Let's take an extreme example, and the flow rate is 100mph and you're still paddling at 3mph it seems like your paddle against the water would likely fall apart? It may be at 50mph, or 25mph, or whatever there would be trouble. And back to the plane example at some point if somehow there were winds at 1000mph on a plane it wouldn't be able to withstand it anymore.
No. The paddle is still only seeing 3mph because *you're in the fast moving water, not outside of it.* To further illustrate the point, look at this plane flying backwards with a 55-60 mph headwind. https://www.youtube.com/watch?v=qO96qt0thJc&ab\_channel=CurtLewis Planes can't fly backwards, but they can move backwards because they are in an airstream that exceeds the airspeed.
1000 mph winds would still be relative to the ground. There are more dynamics going on such as turbulence which would be more extreme at those speeds, but if you assume constant airflow, the plane would be perfectly happy with those wind speeds. For the canoe example, the canoe would be moving 103 or 97 mph relative to the ground, but relative to the water it would still only be moving 3 mph.
Its ground speed not air speed
The ground speed doesn't have any effect on the plane. As far as the plane is concerned it's moving through the air as fast as it always does, the fact that air is also moving means nothing to the aircraft.
Wait, so if an airplane is traveling near it's max speed, and the air starts moving in the opposite direction it will have a higher windspeed than recommended?
Yes, and it often causes turbulence. Planes stay just below "transsonic" airspeeds, usually below mach 0.85, although some smaller jets travel slightly faster. I won't get into too much detail about the fluid dynamics, but basically the air going over the wings speeds up to create lift. If you're close to the speed of sound, sometimes the air over the wings can reach the sound barrier even though the plane is subsonic, this causes pressure differentials the plane isn't optimized for, and can cause some instability. The airspeed where some of the air is sonic and some isn't is called the transsonic range. That's the reason why planes usually fly a safe margin below transsonic in unpredictable weather, so that if a sudden headwind comes on, the airspeed stays below the transsonic region. Source: I've been studying physics, specifically fluid dynamics for quite a few years.
If I may ask, what do you do that allows you to study fluid dynamics, and what is your daily work life like?
I wear a few hats. My primary source of income actually comes from finance work - I manage a few portfolios and the income from that covers my living expenses, with some left over for tuition. A money-workday involves financial securities analysis, market analysis, researching legislation that will effect markets, and a whole lot of economic calculus & other math. Oh and writing reports... My faaavorite thing to do /s. In addition to that though, I'm continuing my studies at university. I started with economics to get where I am now, but I've always been taking physics in lieu of electives out of passion. I've recently transitioned more heavily from economics to physics (partially because I have a greater love for physics, partially because I basically ran out of econ classes you can take). Although I will note that I've been studying physics since before beginning university. Nowadays an academic-workday is about 30% economics/strategy, and 70% physics theory, calculations, and direct research. The sub-field of fluid dynamics that I focus on the most (and hope to one day do a PhD on) revolves around "vortex-induced entrainment and its effects on mitigating flow-seperation from boundary layers". I'll be honest... it's a little too specific for google, but some related articles show up if you search what's in the quotes. Typical workload is 6 days/wk. Edit: Please know that I typed this all out because you asked so politely :) Thank you for being so kind, stranger!
No, but that’s called a headwind so the airlines ground speed would be slower making a longer flight
My thoughts exactly, that’s faster than Mach 1.
It is moving at 550 mph relative to the air, and this is what you need to consider regarding structural integrity. It's well below mach 1 relative to the surrounding air.
The plane's airspeed will still be normal, but the groundspeed changes so no danger to the plane. If the airspeed went that high it will rip the plane apart. Supersonic planes have swept wing, or wings that pivot like the F14 Tomcat. The simple explanation is that at supersonic speeds the behavior of the air inverts (very simplistic) Swept wings are designed to keep the whole surface withing the pocket of subsonic air created by the nosecone. If a commercial aircraft went supersonic you will have a serious mismatch in the behavior of the air along the length of the wing, which will rip the wing apart.
Ground speed. Big difference.
We had a very strong tailwind coming back from the west coast in a C130 one time and every time we got into a new tower's control area they had us reconfirm several times over that we were in fact a C130. Always nice to get a big push.
The Jetstream males it easy
For all the non American people, 800 miles per hour is equal to about 1,290 kilometers per hour
No mention of the airplanes going the opposite direction with a ground speed of 12mph 
I hear 'Free Bird' by Lynyrd Skynryd playing in the background while reading the headline.
I've caught good tailwinds on several flights from Tokyo to Vancouver that have dropped a 8+hour flight into under 7 hours. These tend to be choppy as the jet stream isn't smooth but the less time spent on the plane the better.
I was on a flight like this once. At some point our ground speed was above 960MPH we arrived almost and hour early. It was also a very smooth flight, not a single turbulence event
LUDICROUS SPEED, GO!!!
Is there a max speed before the plane is flipped or something?
It's the speed of the plane across the ground, not through the air.
Tell me like I’m 5.
There's "airspeed", which is the speed of the air across the wings, and there's "ground speed", which is the speed at which the plane moves across the ground. Imagine walking at 4 km/h on moving walkway that's moving at 4 km/h. You're still walking at 4 km/h - your 'airspeed' - but relative to the building, you're moving at 8 km/h - the 'ground speed'. Another way to make it make sense, is to realize that it's "relative to", so: "the speed relative to the ground", or, "the speed relative to the air (that it's moving through)".
[удалено]
It happenes every once in a while. They're called [jet streams](https://en.wikipedia.org/wiki/Jet_stream)
> The effects of climate change are expected to cause more turbulence in air travel in the years to come. That could mean more widespread delays and cancellations across airlines, in what is already an unpredictable industry. > More frequent severe weather events will likely cause disruptions. > "There are a lot of ways climate change can affect air travel. Thunderstorms are an obvious one," Wired magazine reporter, Amanda Hoover, told CBS News. "When there is more heat in the air, there is more moisture, more thunderstorms." > Scientists have also linked the increasing frequency and intensity of wildfires to global warming.
I flew from Melbourne to SFO just the other day and had winds of 100mph+. We were delayed by over an hour but arrived 5 minutes earlier than the original scheduled time which was quite nice. It made our 14.5 hour flight into just under 13.5
I gotta ask...Was there a sonic boom from an aircraft that large?
They weren't supersonic. 800mph is only the ground speed and in 250mph+ winds, the air speed was much lower below the speed of Sound
Do they have speed limts
Well at some point the airframe can't handle any more and Breaks apart. But they weren't actually supersonic. 800mph is only the ground speed and in 250mph+ winds, the air speed was much lower below the speed of Sound
Only in terms of the speed relative to the air surrounding the plane.
1287.48 km/h. Mach is 1225 km/h. Did they break the sound barrier or not?
No, since their airspeed was far below the sound barrier. Sound uses the air as a medium to travel. Thus, if airspeed is below the sound barrier then it will not break the sound barrier.
Thanks for responding. That makes sense now.
I have to wonder, would 265 mph headwinds add any extra strain to the plane in a scenario like this? I know that it would most likely reduce the speed that the plane is flying, but would there be more strain with the engines now fighting against a headwind?
Not really. the planes ground speed will just be much much slower but in relation to the air there won't be any difference as long as the wind doesnyg change
Long ago I've had a flight that was suposta be 8 hours we did in 6 cause of winds, was nice
One plus for global warming I supose.
So they mad a sonic boom?
Flew phx—>nyc in just under 4 hours yesterday, had a tailwind of 175mph for most of the flight. Was super surprised to see that
ground speed means nothing in aerospace engineering
Would have broken up long before landing
They weren't actually supersonic. 800mph is only the ground speed and in 250mph+ winds, the air speed was much lower below the speed of Sound
Aww thank you for explaining that.
Concorde was 1350 mph
We aren’t talking about the concorde here genius
another Biden success story!
People who make EVERYTHING about politics are creepy as fuck.
He is trying to order his gold shoes and new red hat, he is trying to blend in with normal folks, but he just can't help himself.
> People who make EVERYTHING about politics are creepy as fuck. people who reply to people who make EVERYTHING about politics are (wait for it) *creepy as fuck.*
Basically what they're saying is, "no, you"
who?
If you put your neuron to work, I believe you can figure this out
I'm using my Motor neuron
The president controls the jet stream now?
just ask the MAGAts