Radio Procedure - Runway ID

"Matt Whiting" wrote in message


I've had at least 6 different instructors and none have ever suggested a
leading zero on a runway designation. I do believe that leading zeroes
are expected, however, on headings.

Headings are always three digits. Runways never are.

Newps wrote:




"Matt Whiting" wrote in message



I've had at least 6 different instructors and none have ever
suggested a leading zero on a runway designation. I do believe that
leading zeroes are expected, however, on headings.


Headings are always three digits. Runways never are.

I know. The interesting question is why?

Matt

"Matt Whiting" wrote in message
...
Newps wrote:




"Matt Whiting" wrote in message



I've had at least 6 different instructors and none have ever suggested
a leading zero on a runway designation. I do believe that leading
zeroes are expected, however, on headings.


Headings are always three digits. Runways never are.

I know. The interesting question is why?

Maybe because runways are only one or two digits?

Matt Barrow wrote:
"Matt Whiting" wrote in message
...

Newps wrote:




"Matt Whiting" wrote in message


I've had at least 6 different instructors and none have ever suggested
a leading zero on a runway designation. I do believe that leading
zeroes are expected, however, on headings.


Headings are always three digits. Runways never are.

I know. The interesting question is why?


Maybe because runways are only one or two digits?

So? Runways can be two digits, so why not pad to two for single digit
runways? This is the same as padding to three for a heading.

I think an earlier poster was probably right when he said that runways
are in essence named, rather than representing a numeric value.


Matt

"Matt Whiting" wrote in message
...

Headings are always three digits. Runways never are.


I know. The interesting question is why?


Because, unlike headings, runways are always rounded off to the nearest ten
degrees.

"Steven P. McNicoll" wrote in message
ink.net...
Because, unlike headings, runways are always rounded off to the nearest
ten degrees.

True...headings are always rounded off to the nearest one degree. There IS
a difference after all!

The implication of your explanation is of course that things that are
rounded to the tens place should only be the number of digits required to
represent those numbers, but things that are rounded to the ones place
should be three digits?

Hmmm...there's something wrong with that logic, but I can't quite put my
finger on it.

Because, unlike headings, runways are always rounded off to the nearest
ten degrees.

I'd say that the fact that headings are equal to their value, whereas
runway designations are not (they are equal to roughly ten percent of
their value, with exceptions) is closer to the reason. Runways are not
merely "rounded off", rather, the last digit of their magnetic heading
is ruthlessly ripped away after the roundoff process has taken place.
And even then, some runways are given different names ("Sorry, 9 is
already taken, how about 8?") for convenience. After all, it's better
than having runway "nine all the way left", runway "nine sort of left",
runway "nine right, looks like rightmost but isn't" and "nine so far to
the right it looks like another airport tucked in the corner".

Jose
--
Money: what you need when you run out of brains.
for Email, make the obvious change in the address.

"Jose" wrote in message
news
Because, unlike headings, runways are always rounded off to the nearest
ten degrees.

Please be more careful with your quotes. You replied to my message, but
quoted nothing that I wrote.

I'd say that the fact that headings are equal to their value,

They are only "equal to their value" within one degree.

whereas runway designations are not (they are equal to roughly ten percent
of their value, with exceptions)

The precision is different, but the accuracy is exactly the same.

is closer to the reason. Runways are not merely "rounded off", rather,
the last digit of their magnetic heading is ruthlessly ripped away after
the roundoff process has taken place.

That's simply a savings in representation. Just as the "minus" sign is
dropped from temperatures above a certain altitude in the winds aloft
forecast.

And even then, some runways are given different names ("Sorry, 9 is
already taken, how about 8?") for convenience. After all, it's better
than having runway "nine all the way left", runway "nine sort of left",
runway "nine right, looks like rightmost but isn't" and "nine so far to
the right it looks like another airport tucked in the corner".

Now you're getting somewhere. Indeed, runways ARE named, and two parallel
runways have have different "numbers", if they've run out of L's, R's, and
C's to tack on to the runway number.

Personally, I tend to think of runway numbers as labels, and not headings,
though of course the number is suggestive of a heading. But if one is going
to argue against interpreting them as headings, one ought to at least stick
with solid reasons grounded in reality, rather than imagining some arbitrary
differences that aren't relevant.

Pete

The precision is different, but the accuracy is exactly the same.

No, the accuracy is not the same. Due to magnetic drift over time, and
due to values of convenience (such as when there are too many parallel
runways).

is closer to the reason. Runways are not merely "rounded off", rather,
the last digit of their magnetic heading is ruthlessly ripped away after
the roundoff process has taken place.
That's simply a savings in representation. Just as the "minus" sign is
dropped from temperatures above a certain altitude in the winds aloft
forecast.

That kind of change is significant, especially when what is left looks
like a (different) number.

Jose
--
Money: what you need when you run out of brains.
for Email, make the obvious change in the address.

Jose wrote:
Because, unlike headings, runways are always rounded off to the
nearest ten degrees.


I'd say that the fact that headings are equal to their value, whereas
runway designations are not (they are equal to roughly ten percent of
their value, with exceptions) is closer to the reason. Runways are not
merely "rounded off", rather, the last digit of their magnetic heading
is ruthlessly ripped away after the roundoff process has taken place.
And even then, some runways are given different names ("Sorry, 9 is
already taken, how about 8?") for convenience. After all, it's better
than having runway "nine all the way left", runway "nine sort of left",
runway "nine right, looks like rightmost but isn't" and "nine so far to
the right it looks like another airport tucked in the corner".

No, headings are just rounded to a different level. A heading can
certainly can be a real number, it doesn't fundamentally have to the
ones digit.

Matt