IFR Enroute chart question

[brien23]

IFR Enroute NOS chart vor the airways have heading out some have a degree marking after the heading number some do not 250---or 250*----
What is the degree after the heading?

 

[TMetzinger]

care to give an example? chart number, VOR, and airway, please.

I don't THINK it matters, but would have to look.

 

[roncachamp]

IFR Enroute NOS chart vor the airways have heading out some have a degree marking after the heading number some do not 250---or 250*----
What is the degree after the heading?

What VOR?

 

[brien23]

care to give an example? chart number, VOR, and airway, please.
Palmdale PMD V386 Heading from the VOR 233----- and 081*-----

 

[twdeckard]

A random survey on Skyvector indicates this is very prevalent.

L-12 PIR (but I think you could pin the tail on the VOR and find one) some have the degree marking some don't.

Its a good trivia question.

 

[BillTIZ]

care to give an example? chart number, VOR, and airway, please.
Palmdale PMD V386 Heading from the VOR 233----- and 081*-----

Just guessing here... V386 easy bound out of Palmdale is the 081 radial.
Because of the font they use.. 081 could be 180 if read upside down so they need something to differentiate the Radial. Find some other airways on the 180R and you might find the same annotation 180*.

 

[twdeckard]

Just guessing here... V386 easy bound out of Palmdale is the 081 radial.
Because of the font they use.. 081 could be 180 if read upside down so they need something to differentiate the Radial. Find some other airways on the 180R and you might find the same annotation 180*.

your smart!

Surfing on skyvector would confirm your theory. Only those that would be ambiguous if you read them on your head seem to be ornamented with the degrees. I'm buying it.

 

[roncachamp]

IFR Enroute NOS chart vor the airways have heading out some have a degree marking after the heading number some do not 250---or 250*----
What is the degree after the heading?

care to give an example? chart number, VOR, and airway, please.

I don't THINK it matters, but would have to look.

Palmdale PMD V386 Heading from the VOR 233----- and 081*-----

IFR enroute charts do not show headings, they show VOR radials. On the west side of PMD the 233 radial defines V386, on the east side it's defined by the 081 radial.

 

[brien23]

IFR enroute charts do not show headings, they show VOR radials. On the west side of PMD the 233 radial defines V386, on the east side it's defined by the 081 radial.

Yes you are right they only show the radial but what is the degree marking after the 081*-------- and not shown on the 233--------

 

[gprellwitz]

Only 5 digits can look like digits no matter which way they're turned: 0, 1, 6, 8, and 9
There are only a few radials that could be so confused:
001 = 100 (PIR V120)
011 = 110
060 = 090 (RWF V412)
061 = 190
081 = 180 (PMD V386)
091 = 160 (MHE V120)
161 = 191

They don't need to mark:
010
080
111
181
and I found some instances of 080 that weren't marked.

Enough for me to be convinced!

BTW, note that on sectionals they seem to use degree marks for ALL of the Victor radials.

 

[John Collins]

IFR enroute charts do not show headings, they show VOR radials. On the west side of PMD the 233 radial defines V386, on the east side it's defined by the 081 radial.

All true.

The radial is not necessarily the same as the actual magnetic bearing from the VOR. When the VOR is installed, it is aligned to magnetic north. Over time, magnetic north moves, but the orientation of the VOR and the radial that is used to define an airway or intersection does not move. Eventually the VOR can be readjusted to align itself with magnetic north and all the airways and intersections defined by the VOR which appear on any chart need to be updated. This can be a time consuming and expensive process. It is not uncommon for radials to be 3 or 4 degrees off of the correct magnetic value and accounts for some of the differences between what your GPS says and what the VOR says.

 

[EdFred]

pedantic
–adjective: overly concerned with minute details or formalisms

 

[AdamZ]

IFR Enroute NOS chart vor the airways have heading out some have a degree marking after the heading number some do not 250---or 250*----
What is the degree after the heading?

This by the way is an excellent thread. Thanks for posting it.