Why The Hell... (random rant)

On Apr 4, 7:47 pm, Mxsmanic wrote:
Ron Natalie writes:
No you are confused. Magnetic SOUTH is the exact opposite of magentic
north you fool. The fact that the MAGNETIC SOUTH POLE is not exactly
opposite the MAGNETIC NORTH POLE is a different issue.

I assumed that others would understand this, but I often get into trouble when
I assume others will understand things.

The fact that
the poles aren't aligned with the arbitrary "true" datum just means that
the variation equations aren't as simple as they might be.

They are more than just misaligned: they are not at opposite points in terms
of longitude and latitude, either. A line drawn between them does not
intersect the center of the Earth.

I do very few flights to the center of the earth: I know that's the
first place you'd head for if someone was dumb enough to trust yuo
with a real airplane; though::
So how often do you fly using just your magnetic compass alone?

Every week, fjukkktard.



Bertie

On Apr 5, 3:11 am, Mxsmanic wrote:
Nomen Nescio writes:
The category that has wings and goes up in the sky.

You mean like a 747-400? It has two GPS receivers, three IRUs, two VORs and
two ADFs. One rarely falls back upon the magnetic compass.


You're obviously not fa,iliar with the limitations of an inertial
system, fjukkwit:

Hell, you're not even familiar with the limitations of the doorknob on
your bedroom door,

Bertei

On Apr 4, 7:55 pm, Mxsmanic wrote:
Ron Natalie writes:
So that they line up with the compass. All in-flight
navigation is magnetic based.

Some transoceanic flights might disagree.


No they wouldn't fjukktyard: We use true only when necessary.

Bertie

On Apr 5, 7:31 am, Mxsmanic wrote:
Jose writes:
"It must be true - I found it on the internet"

I think you'll find that the more you research about the geomagnetic field,
the less reliable you find it to be for navigation.

I think you'd find that if you flew, you'd find that you don't know
**** from shinola:

I've crossed oceans, preGPS and with no inertial systems,; and ended
yup withina few miles, which is the same accuracy as an INS BTW, of my
landfall target:

You; OTOH; sit in your room and jerkooff



Bertie

On Apr 5, 12:02 am, Mxsmanic wrote:
writes:
Sorry, I have to mildly disagree as far as flying goes, that you'd
automatically be in "deep trouble". Many pilots use just the
compass / DG for cross-country flying.

A compass / DG is not just a compass.

You can't do much with just a compass alone. You need a clock, some charts,
other things ... not _just_ a compass.

Therefore a simple compass
was "good enough" for winged flight across the Atlantic starting in
1919. which is not "four hundred years" ago.

They had more than a simple compass. In particular, they had accurate clocks,
and charts.

Yeah, nice to have charts of course 'yo look, Alcock, there's a Whale.
I'll just check it against position'


Fjukkkwit:


Bertei

On Apr 5, 5:33 pm, RomeoMike wrote:
DR wrote:

Declination in navigation is actually

something else but I'll let you googgle for it.

I'm not sure that's really true. In aviation we talk about variation,
but when I'm using 7.5' topo maps on the ground, declination is the term
used for the difference
between magnetic and true north. (See the bottom left of a US DOI
Geologic Survey 7.5' topo.)
Variation and declination are defined the same
If there's a more sophisticated use of the word declination in
navigation, I'm willing to be enlightened.

OK, it's celestial Nav. Stars are located by declination (angle from
the celestial equator) and RA. The geographical use of declination to
describe variation is the result of bad education propagating a
specilaized technical term into incorrect use IMHO. As I think about
it, how could a word derived from "decline" be related to horizontal
angle...?

Cheers MC

On Apr 5, 5:37 am, "EridanMan" wrote:
On Apr 4, 5:23 am, "Steven P. McNicoll"
wrote:

"EridanMan" wrote in message

roups.com...

Why in gods name are VOR's Mag heading based?

Tradition.

Best answer I've heard yet

Isn't the difference between your compass heading and the radial you
are flying the drift? Knowing drift is pretty useful...

Cheers MC

On Apr 5, 4:35 pm, wrote:
In rec.aviation.piloting DR wrote:

Mxsmanic wrote:

There
are plenty of spots on charts where the compass will be 6-8 degrees off even
from the already irrgular declination over larger areas.

LOL! My BS meter just went off scale! Declination? Lines of magnetic
_variation_ are plotted on VP charts and better than 0.5 degree accuracy
(except at local anomalies which are only noted in nautical charts as
far as I've seen so far). Declination in navigation is actually
something else but I'll let you googgle for it.

I can't think of any local anomaly that is both strong enough and large
enough to be anything other than a transitory "burble" at most to the
compass of an airplane in flight.


Yes, I agree, that is true of most but some are very big, the biggest
is in Kursk, Russia. If your autopilot is flying a magnetic heading
how fast would it respond if it flew over a common 6 degree anomaly?


Cheers MC

Mxsmanic wrote:
Steven P. McNicoll writes:

That would be true if VORs were set to local magnetic variation. They
rarely are.

Which variation are they set to, and how useful can they be if their
orientation doesn't match the local magnetic variation?

Because some were never right. Some where set right but the local
variation has changed and the VOR's were never realigned. It's
not necessary for them to set exact, just that they are known with
a reasonable precision. The fact that they are close to magnetic
north is again as we've been saying, convenience because all courses
and headings IN FLIGHT are done magnetic.

Steven P. McNicoll wrote:
"Ron Natalie" wrote in message
m...
Huh? What does the wind have to do with VOR's. If the needle is
centered, you're within the tolerance of the VOR. The tolerance
is primarily 4-6 degrees. This keeps you inside the airway at
moderate distances from the VORs.


What about at more than moderate distances from the VOR? At 40 miles from
the VOR 6 degrees is 4 miles.


At 51 miles, 4.5 degrees gives you 4 miles. 6 degrees gives you about
6. Theres' 2 miles of protected area outside the airway.
Statistically you're within it, but even in the worst case you're
safe.