Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

[Fwd: Flight from San Francisco to New York]

Maybe someone can help these folks! at Stumpers-L it's a great site for
anyone's general education. It answers questions which have stumped
reference librarians
--- Begin Message --- A patron brought this question to a reference desk in the next county,
which has passed it to us:
"Why would it take a plane flying non-stop from San Francisco to New
York longer than the same type of plane flying from New York to San
Francisco, when weather, speed, wind, and flying conditions are exactly
the same each way?"

I put the question to a meteorologist/physicist who works for an Air
Force contractor. He replied:

"The only two possible answers I can think of are: (1) The wind speed
is the same -- west to east -- which is almost always the case, so the
trip from NY to SF is flying into a head wind. Or (2) some second-order
relativistic effect that I don't understand -- why would the direction
make a difference?"

When I asked whether the rotation of the earth would have an effect, he
replied:

"No really, The air is also rotating with the earth (apart from the
average west to east wind at mid-latitudes and at aircraft altitudes).
If the coordinate system is fixed on the rotating earth, then the
rotation rate of the earth should not affect the velocity of the
aircraft, assuming it travels at the same velocity (a tautology, I
know). The rotation of the earth will exert a coriolis force on the
aircraft, which is a force to the right (in the Northern Hemisphere) of
the line of travel. But if the aircraft compensates for this force, its
speed should not be affected."

(Whatever that means.)

Anyone else wanna take a stab at it?

Chris Gallery

(I apologise for the sig file / card mess at the end of my messages
lately -- new program, I'm puzzling about how to make sense of it.)
begin: vcard
fn: BLIC
n: ;BLIC
org: Black Gold Cooperative Lib Sys
adr;dom: P.O. Box 1019;;;Santa Barbara;CA;93102;
email;internet: bginfo@rain.org
tel;work: 805/963-1397
tel;fax: 805.962.1840
x-mozilla-cpt: ;0
x-mozilla-html: FALSE
version: 2.1
end: vcard


--- End Message ---