Does an aircraft travel in a straight line?

[timeoff]

It might make it until morning. Nice jublies I might add.

 

[TriStar_drvr]

When I transitioned off of glass back to steam guages for a short period the instuructor said, "just fly straight and level." "Sure I said, which one do you want first?"

We need more posts like this on this board. Thanks, Groucho.

 

[I fLy pLaNeS]

Moving with the Earth

How about a flight from the far Northern Hemisphere to the far Southern Hemisphere? Are we traveling with the Earth's rotation as long as we hold the magnetic course? Ah....nevermind :erm:

 

[Gorilla]

I can't believe no one's given a "straight" answer... the shortest distance between two points on a globe is a great circle route. It's easy to visualize. Find a globe, grab a string, and stretch the shortest length possible that will fit between the great State of TX and Tokyo. The string will fly up to the Northwest, along the Alaska coast, down the Aleutians, maybe across Kamchatka, and on to Tokyo. If plotted on a flat map, the route looks like a thrown baseball, arcing up, then down.

The heading required to fly the route will change continually the whole flight. But in terms of miles flown, and fuel burned, it is the best route, winds ignored.

Same deal TX to London. It's across the North Atlantic, not the mid atlantic.

 

[CE402]

Ok....what if you dug a hole (big enough for you to fit in) straight through the Earth to the direct opposite side. Take away temperature change as a factor (assume you're protected from it).....
....you jump in....what happens?

 

[QuasarZ]

Ok....what if you dug a hole (big enough for you to fit in) straight through the Earth to the direct opposite side. Take away temperature change as a factor (assume you're protected from it).....
....you jump in....what happens?

I have always thought about this as well.. So if you go in feet first, will you come out upside down? Or will you get stuck in the middle because of the gravity?? I say we need to do a really big experiment and find out....

 

[tomgoodman]

Assume no "perturbing" factors such as a non-uniform earth, the moon's gravity, air friction, etc.---you'd have a huge, endless bungee jump from surface to surface. Add in some friction, and it damps to zero movement, weightless at the earth's core.

Here's another: You're in a boat on a lake and you throw a brick overboard. Does the level of the lake (measured at the shoreline) rise, fall, or stay the same?

 

[Fugawe]

Ok....what if you dug a hole (big enough for you to fit in) straight through the Earth to the direct opposite side. Take away temperature change as a factor (assume you're protected from it).....
....you jump in....what happens?

Your kids get your inheritance.

 

[Fugawe]

Hmmm, how 'bout this one!

Say a plane is on a treadmill...............................


Fugawe
-just shoot me

 

[A Squared]

yep these guys are right, not a straight line.
Keep in mind that the world is huge compared to your little plane, so if you traveled from point A to B, but flew it all at FL300, how much curvature is really involved? A few feet?

About 980 ft of curvature for each 60 NM

What about this--- let's say A to B is 1000 miles if driven by a car on a perfectly flat, driect road. If you provided "cover" for that car (let's say you're carrying some GBU-38s), but you're at FL300, how far are you really going? It's definitely more than 1000 miles. Some math nerd here can probably give you a perfect answer by using some simple trigonometry and the radius of the Earth.

1001.4377 miles.......aproximately

Here's another: You're in a boat on a lake and you throw a brick overboard. Does the level of the lake (measured at the shoreline) rise, fall, or stay the same?

It goes down

 

[iflyjets4food]

Hmmm, how 'bout this one!

Say a plane is on a treadmill...............................


Fugawe
-just shoot me

It will take off.

 

[sleddriver71]

Assume no "perturbing" factors such as a non-uniform earth, the moon's gravity, air friction, etc.---you'd have a huge, endless bungee jump from surface to surface. Add in some friction, and it damps to zero movement, weightless at the earth's core.

Here's another: You're in a boat on a lake and you throw a brick overboard. Does the level of the lake (measured at the shoreline) rise, fall, or stay the same?

I'm not sure. The weight of the brick is pressing down on the boat which is in turn, displacing water. My gut answer is that the level of water will stay the same. Obviously (in my head) if you tossed the brick in the lake while you were standing on the shore, the level of the lake would rise. Yea, I think it would stay the same...

 

[AirBadger]

Get a record player, put a vinyl on it and while its playing take a ruler and draw a straight light from the center to the outer edge with some chalk. Then stop the record player and notice that it is a curved line. The Coriolis affect applies to everything, including airplanes.

 

[A Squared]

I'm not sure. The weight of the brick is pressing down on the boat which is in turn, displacing water. My gut answer is that the level of water will stay the same. Obviously (in my head) if you tossed the brick in the lake while you were standing on the shore, the level of the lake would rise. Yea, I think it would stay the same...

Yeah, at first blush it seems that way....but, the reason the water level will go down is because the brick is more dense than water (It sinks, therefore it is more dense) In order for the boat to float, it has to displace a volume of water which has a weight equal to the weight of the boat. Say the brick is 5 lb. 5 lb of water is about 2.5 quarts. but the brick is smaller than 2.5 quarts, because it is more dense than water. So when you take the brick out of the boat the boat displaces 2.5 quarts less water and the water level in the lake goes down. Now put the brick in the water, and it sinks, and displaces water, but it displaces *less* than 2.5 quarts, so the water level goes back up a little, but not as much as it went down. net result, the water level is lower after the brick is in the water.

 

[Amish RakeFight]

Colored airways? What did I miss?

The rainbow.