Posted on 12/23/2016 12:50:57 PM PST by Allen In Texas Hill Country
In a few days were flying to Rio. Down there. It'll take about 12 hours from Atlanta. And then I got to wunderin'. When flying east to west or vice versa the destination kinda always stays somewhat ahead of you. Flying west bound might be a bit quicker for a given distance because the destination is rotating towards you. Not too big a deal.
Now flying for 12 hours in a southern direction the earth can rotate 180 degrees. Rio will have moved 180 degrees to the east. So here is the question,,,,,,,,,,,,,Does the navigator/flight computer immediately direct the plane to fly to the location where Rio will be in 12 hours or something else?
No. The plane is in relative stasis on the earth along with the landmarks. Rotational orientation of the earth has no effect. Think of atmospheric space as a solid (gel like) mass joined to the planet.
The only difference would be in the prevailing winds. (Headwind vs Tailwind)
That’s right.
And if you jump up in the air, and stay levitated for 10 hours you will land in China.
I’m assuming you’re joking.
Sort of like ejecting anything from a moving spacecraft. That which is ejected is still moving at the same velocity as the spacecraft...unless some other force acts upon it.
The atmosphere travels with the earth at the same relative speed so it doesn’t matter which direction you fly.
I was hoping to land in Southern France.
If you were in outer space you would be correct. But, you are still attached to earth (even in a plane.)
The navigator would make a route based on the grand circle, but the relation to the earth would act as though you were connected to the ground with a long stick.
Of course, that leaves me wondering why artillerists and naval gunners need to account for the rotation of the earth to hit long range targets.
This reminds me of th stimulus when a truck driver carrying two tons of canaries in his two ton truck (4 tons total) came to a bridge with a warning sign “Load Limit: 3 tons.”
How did he get safely across the bridge without it collapsing from excessive weight?
You’ll be in the EST plus three. From Texas plus four.
Sugarloaf and Corcovado are must see.
Gorgeous city.
Got them to all start flying?
What is most affected by Coriolis Effect is the horizontal component of the bullet trajectory. Because of the Coriolis effect, every moving object not connected to the ground is always deflected to right in the Northern Hemisphere, and always toward left in the Southern Hemisphere. The deflection is not east or west, but specifically to the right or left with reference to the shooting direction. It doesn’t matter in which direction you shoot; it is a function of latitude and average bullet speed. Its effect is maximum at the poles, and decreases as one moves toward the Equator, where it is minimal. The explanation of this phenomenon is more difficult than the explanation of Eötvös Effect, so I won’t go into it into detail.
Here’s an example of error due to Coriolis effect: firing the same .308 175gr bullet at 2700fps muzzle velocity, from a latitude of 45° in the Northern Hemisphere, the deflection at 1000yds will be of 3in to right. At the North Pole, where the effect is maximum, the deflection will be a little more than four inches. The deflection will be the same in the Southern Hemisphere, but it will be to the left, instead.
As you can see, these errors are subtle, even when shooting long distance.However, especially when combined with other potential error factors in your long distance shooting equation, it could make the difference between hitting and missing your target. If you have portable ballistic software, you can use it to calculate Coriolis for you at every distance. But, if you’re doing the math on your own, I wouldn’t start to take Coriolis into consideration unless shooting at 1,000 yards, or more.
Ok, here’s one.
You have a helium balloon in your car with you and you slam on the brakes.
What happens to the balloon?
First I’ve heard of that. I know they have to take the winds into account.
Sugarloaf and Corcovado are must see.
Gorgeous city.
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Yes, thats one reason we wanted to go back.
And Babe Ruth really did not hit the baseball all that far.
He would hit the ball and the fences, which are in fact attached to the earth, which is of course moving, causing the ball to land on the other side of the fence.
Home Run!
I’m having a hard time assimilating the responses. One entry talked about the effect of winds and another insinuated that winds don’t count because the atmosphere is a gel/solid that rotates with the earth.
I’ve always kinda thought that weather/winds generally move from the west to the east in the northern hemisphere. That is with but ahead of the earths rotation. But doesn’t weather move from east to west in southern hemisphere?
I’m going to try and have a chat with a flight officer out of curiosity.
Former USAF navigator here....several responses are pretty good.
No more navigators on ( modern ) airlines. They have been replaced by computers relying on GPS and other means.
The GPS will fly a great circle route direct to Rio. The GPS will take into account winds and the coriolis effect.
But there is no need to fly to where Rio will be in 12 hours. Just fly where it is now.
There are some internet sites which will calculate the great circle route so you can see where you’re going.
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