jeffies, you really, really, really need to have your wife check your posts
before you hit the send key.

jeffies, you definitely said *you* know where *you* are because you have
reference points in DR.

Show us where I said that. You're fantasizing an entire discussion, jaxie.

one post up, and the entire post below

you ONLY have where you started

That's one reference point ...

it is no longer a reference point once you have moved, for you no longer know
where it is. that is a fact of physics (which you said you have a degree in)

which direction mag North
is.

That's another reference point.

really? so, if that is true and you know North is "thata way" where on the
planet are you?

Hell of alot better than Jax.

Joe


yup, joe, you sure are one incredible alchemist. you can perform precision
math on guesses and turn them into precision guesses. I am impressed.

whatever their speed and direction relative to your speed and direction. is
that hard for you to understand, over the knee?

But to claim that there is "no qualitative difference between navigating" a
plane and boat just shows you have no practical experience doing either.


quite the contrary. it shows I have done both.

actually, in air nav you don't have to make as much allowance for winds,
for
the speed of the an airplane is many times the speed of the winds, for the
aircraft flights under discussion here.


Oh? How much allowance do you give for currents on these airplanes?

otn

gee, over the knee, just when you seem to be starting to grasp the elemental
concepts you blast off into you spirally world again, lost to the real world.

ROFLMAO How do you come up with these responses?!!

otn

JAXAshby wrote:
over the knee, it sounds like you are starting to back peddle in
anticipation
of **finally** understanding the concept of relative motion.


maybe, over the knee, you don't know what reference points are, or what
constitutes a reference point. jeffies, doesn't/didn't.

like Ragu, "It's in there".

jax, you really,really do need help with "reading comprehension".
You can't just take what someone writes and interpret it to suit your
needs or point of view ..... go back and read what he said, then before
you write something, take the time to think what it means.

otn

verifying a new to you concept by checking with those educated in the hard
sciences in the specific area under discussion is something that makes you
laugh, over the knee?

how sad.

ROFLMAO ....

JAXAshby wrote:
over the knee, it is physically impossible to know where you are without
outside references. if you doubt that, call any local college tomorrow
morning, ask for the physics dept and ask the first TA who answers the
phone.
Don't be bothered that he or she is only maybe 19 years old. he or she
knows
the answer even if you don't.


You are wrong when you say "DR" is never dead on (but that's beyond
your knowledge or experience).


absolutely not. it is physically impossible. period. (except by
random
chance, but that defeats the definition).

ROFL. Jax, we all ready know you don't understand the terms used in
"DR", or how it can be applied/used, and the possible variations in
meaning that others may have for the term and it's use.
How then could we expect you to understand that "DR" can be "dead on" in
many cases, but your total lack of experience and low levels of
comprehension put this possibility way beyond your ability to understand?

otn

nav, are you saying that making more guesses *improves* the accuracy of prior
guesses?

mathematically, additional guesses degrades the accuracy of prior guesses.

what's more, aircraft also make leeway and also have current and actually have
air density differences (similar effect as the tide you mention re boats)

List Jackass and listen good. DR in flying is just compass and speed. In
marine navigation it is compass, speed, leeway, current and tide. By
allowing for these variables accuracy is much greater.


Cheers

JAXAshby wrote:

jeffies, you definitely said *you* know where *you* are because you have
reference points in DR. listen to me. you do NOT have reference points in
DR.
you ONLY have where you started (and you don't even know where that is
once
you have started), your speed through the medium and which direction mag
North
is. That's it.


No jaxie, I didn't mention "known ladmarks" and I wasn't referring to
"pilotage." Its very simple: any DR plot begins with a known reference
point
called a "fix." If you knew anything about DR you would understand that.
I
would guess that most pilots know what their starting point is - that's a
reference point.




"JAXAshby" wrote in message
...

jeffies is not smart (without asking his wife) to use the word "pilotage".

he

merely said something about known ladmarks. same same.


I didn't see anywhere, where Jeff introduced "pilotage" in a way to
change the definition.

In other words, this discussion has gone way beyond your limited capacity to
understand.

Its very simple, jaxie: a 20 knot crosswind affects a 100 knot airplane about
the same way that a 1 knot cross current affects a 5 knot sailboat. There is a
major difference, however: the wind can change dramatically with little notice
and no way to detect it, resulting in huge potential errors for the plane, while
the current is usually well behaved, especially if you understand the local
conditions.

You never have done either, have you jaxie?



"JAXAshby" wrote in message
...
jeffies, pahleeeeeeeeeeeeeeeeeeeeeze ask your wife to read every last thing
you
write **before** you hit the post key. that way we won't see the trash you
wrote below.
PLEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEAAAAAAAAAAAAAAAAAA AAAASSSSSSSSSSSSSSSSSSSS
SSEEEEEEEEEEEEEEEEEEE. okay?

There are no aircraft flights under discussion here. However, if we're
talking
about planes where electronics might not be used, then the speed is probably
rather low, and the wind speed could easily be 20% of the plane speed.
Worse,
you could have a significant wind shift and have no idea it happened. In a
boat, the currents are usually under a knot, and rarely is the deviation from
the prediction more than knot. You seem to be basing your entire claim on
the
possibility of unexpected 10 knot current in totally random directions. This
show your complete lack of experience.

Further, your completely ignoring that fact that for piloting, a major part
of
navigation, there are many techniques that have no analogue in flying. But
you
wouldn't know anything about this, would you?




"JAXAshby" wrote in message
...
But to claim that there is "no qualitative difference between navigating"
a
plane and boat just shows you have no practical experience doing either.

quite the contrary. it shows I have done both.

actually, in air nav you don't have to make as much allowance for winds,
for
the speed of the an airplane is many times the speed of the winds, for the
aircraft flights under discussion here.

so, nav, because I know that science stuff while you don't that means "that
science stuff" does not affect where *you* are when *you* are wondering around
in a fog with only a compass and speed indicator?

how sad that you think ignorance protects you.

Yes that about sums your knowledge up.

Cheers

JAXAshby wrote:

yeah, all that physics science stuff.

Every DR plot starts with a FIX. Its just that simple, jaxie, live with it.

Perhaps you should go back to that Power Squadron course you dropped out off -
they'll probably let you in so you can learn about this stuff.



"JAXAshby" wrote in message
...
jeffies, **if** you know where you are using known (sic) reference point, THEN
that is called pilotage, not deduced reckoning.

you have changed the definition of the term DR to that of pilotage. you can
change it to green Shinola if you wish but it still doesn't make it safe to
wonder around in a fog with rocks anywhere near by.

I never made any such claim. In fact, I was only asserting the simple fact
that
DR does involve known reference points.

I've never claimed the DR was "precise," I've only claimed that it is good
enough to be useful, and a necessary skill for any skipper that wishes to be
competent.

You're the one who claims that DR is so worthless that navigation without GPS
is
physically impossible. And since you've admitted to being lost with two
functioning GPS's onboard, its a good thing you don't actually go sailing at
all.



"JAXAshby" wrote in message
...
over the knee, jeffies brought it up as proof that DR was precise
navigating,
not me.

jeffies is not smart (without asking his wife) to use the word
"pilotage".
he
merely said something about known ladmarks. same same.


I didn't see anywhere, where Jeff introduced "pilotage" in a way to
change the definition.



..... and you, typically, took it out of context, and created a new
argument, which was unrelated to the discussion at hand, and tried to
pawn it off as "someone else said".
Lame attempt, try again.

otn