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Kestral757
13th May 2009, 21:41
Hi guys ive got an air nav test tommorow and its likely this question will pop up but im not 100% sure what the answer is, according to a PPL Nav book i have it says a Rhumb line crosses longitude meridians at the same angle,where as on web pages it says it crosses all meridians at the same angle, a great circle path is the shortest distance between two points however they are different depending on what chart you use conical or mercator,any help much appreciated !

A Rhumb line track can be described as:
(a) A track that crosses all lines of latitude at the same angle
(b) A track that crosses all lines of longitude at the same angle
(c) The shortest distance between two points
(d) A great circle path

Adios
13th May 2009, 22:02
A meridian is always a line of longitude, so it would appear the web version is no different to the PPL Nav book version. A line of latitude is not a meridian, so the word 'all' only refers to longitude, not both lats and longs.

Meridian Defined:
A meridian (or line of longitude) is an imaginary arc on the Earth's surface from the North Pole to the South Pole that connects all locations running along it with a given longitude. The position of a point on the meridian is given by the latitude. Each meridian is perpendicular to all circles of latitude at the intersection points. Each is also the same size, being half of a great circle on the Earth's surface and therefore measuring 20,003.93 km.

MickeyH
13th May 2009, 22:02
I'd go for b) :ok:

Adios
13th May 2009, 22:09
A describes a meridian, not a rhumb line
C describes a great circle path, which a meridian is, but a rhumb line is not.
D describes a meridian, not a rhumb line
B is the correct answer and is the only one that does not describe a meridian

Kestral757
13th May 2009, 22:09
Nice one thanks alot guys very much appreciated!

EGCC4284
14th May 2009, 01:00
Good luck and let us all know how you got on