A few more IFR questions...

[mhcasey]

Hey guys. Just a few quick questions that are probably in the AIM somewhere...

1) What's the difference between green and blue airports on NACO Low Enroute Charts?

2) What's the difference between the A/B suffix on IAP's, aka VOR-A vs VOR-B?

Thanks,

Mike

 

[dc3flyer]

1) Green airports have military approaches and blue ones only have civilian approaches. The only thing you should have to know is that they both have IAP in place. (Also that the brown ones do not!)

2) A -A is the first circling approach, -B is the second, -C is the third, and so on. It doesn't really mean anything else. The letter just means that there is no straight-in.

 

[CameronF]

The post above is wrong about question #1.

Blue and green both have an approved civilian instrument approach published. Whereas "BLUE" also has an approved Department of Defense instrument approach published.

 

[mhcasey]

Thanks a lot DC3. I'll post more under the same thread as they pop up.

 

[dc3flyer]

The post above is wrong about question #1.

Blue and green both have an approved civilian instrument approach published. Whereas "BLUE" also has an approved Department of Defense instrument approach published.

WHOOPS! I got it backwards (told you it wasn't very important:nana2: )

I guess I also should have been more specific about them both having civilian approaches.

 

[meritflyer]

The post above is wrong about question #1.

Blue and green both have an approved civilian instrument approach published. Whereas "BLUE" also has an approved Department of Defense instrument approach published.

I believe this is for NACO charts only.

 

[mhcasey]

And for Jepp Charts it's just Blue has approaches and green is VFR? While I'm on the topic, does anyone have a good link, book, or other source for a good Jepp tutorial or legend? I guess I could just subscribe, but I'm thinking after I get my CFI (hopefully this summer) I really won't be doing that much IFR flying for a while so it might not be worth it.

Here's another question. My local METAR right now:

[FONT=Monospace,Courier]KAUS 150553Z 35012KT 10SM -RA OVC013 02/02 A3018 RMK AO2 UPB13E36RAB17E31B52 SLP225 P0000 60009 T00220022 10044 20022 400560022 51011 $

I've got everything up to P0000. Anyone want to try to decode the rest? I think the T is a more precise temp/dewpoint spread? What else is going on there? AIM chapter 7 isn't giving me any love on that right now...

By the way, if anyone else has any IFR questions, feel free to throw them in this thread.

Thanks again guys.
[/FONT]

 

[Cessnaflyer]

T00220022

Means the temperature is +2.2 and the dew point is +2.2

If it was T10221022 that would then mean that the following temp is negative.

 

[casey]

Here's another question. My local METAR right now:

[FONT=Monospace,Courier]KAUS 150553Z 35012KT 10SM -RA OVC013 02/02 A3018 RMK AO2 UPB13E36RAB17E31B52 SLP225 P0000 60009 T00220022 10044 20022 400560022 51011 $

I've got everything up to P0000. Anyone want to try to decode the rest? I think the T is a more precise temp/dewpoint spread? What else is going on there? AIM chapter 7 isn't giving me any love on that right now...
[/FONT]

Pxxxx is hourly precipitation
6xxxx 3 or 6 hour precip totals
Txxxxyyyy temp/dew
1xxxx 6 hour max temp
2xxxx 6 hour min temp
4xxxxyyyy 24 hour max/min temp
5xxxx is pressure tendancy

so to decode "P0000 60009 T00220022 10044 20022 400560022 51011"

no precip this hour, 0.09" precip in the last 6 hours, temp 2.2C, dew 2.2C, temp spread over last 6 hours 4.4C - 2.2C, temp spread over last 24 hours 5.6C - 2.2C, pressure has increased over 3 hours ago by 1.1mbar but is now steady or rising very slowly.

http://weather.cod.edu/notes/metar.html

 

[MidlifeFlyer]

And for Jepp Charts it's just Blue has approaches and green is VFR? While I'm on the topic, does anyone have a good link, book, or other source for a good Jepp tutorial or legend?

Jepp did a series of "Chart Clinic" articles for AOPA some years ago. Reprints are available at

http://www.jeppesen.com/wlcs/index.jsp?section=resources&content=publications_aopa.jsp

Another idea is to get an expired Express (local area charts) - it will gave all of the legends and explanatory material.

 

[turbojet28]

For the METAR stuff (and all aviation weather products), I would highly recommend the advisory circular titled "Aviation Weather Services". It has everything you ever wanted to know about most of the standard weather products (TAF, METAR, FA, SD, FB, WS, WST, etc.). It is getting kinda old, though.

 

[bdhill1979]

For the METAR stuff (and all aviation weather products), I would highly recommend the advisory circular titled "Aviation Weather Services". It has everything you ever wanted to know about most of the standard weather products (TAF, METAR, FA, SD, FB, WS, WST, etc.). It is getting kinda old, though.

:yeahthat: that book has it all.

 

[fish314]

1)

2) A -A is the first circling approach, -B is the second, -C is the third, and so on. It doesn't really mean anything else. The letter just means that there is no straight-in.

This is exactly right, and they use a very similar nomenclature for multiple straight-in type approaches to the same runway--except they use letters from the back of the alphabet.

So for example, if there are two different ILS approaches to the same runway, one of them will be the ILS Z RWY 16 , and the next will be the ILS Y RWY 16 , and so on.

Here's an example. The RNAV GPS Y RWY 31L, and the RNAV GPS z RWY 31 L:

http://204.108.4.16/d-tpp/0612/00610RY31L.PDF
http://204.108.4.16/d-tpp/0612/00610RZ31L.PDF

 

[mhcasey]

Thanks to everyone.

Now a few more:

If communication is lost above a high overcast layer (we'll say bases above MEA), should you follow lost com procedures as if in IMC, or descend below the layer into VFR conditions (that you are very sure exist below the cloud layer) and land as soon as practicable?

If you're approaching an MCA below the MCA, will ATC assign a new altitude, or do you need to request it?

What is the difference between the OROCA and MIA? OROCA is published on NACO charts, correct?

FAR 91.175 says you can descend below the DH with the VASI in site. Does this apply to PAPI's also? Tricolor VASI's?

Thanks again,

Mike

 

[Ian_J]

Thanks to everyone.

Now a few more:

If communication is lost above a high overcast layer (we'll say bases above MEA), should you follow lost com procedures as if in IMC, or descend below the layer into VFR conditions (that you are very sure exist below the cloud layer) and land as soon as practicable?

You should follow the lost communication procedures for IFR unless in VFR conditions. So, if above a cloud layer you can't decend into it and still be in VFR conditions. You must follow the "highest of" of the Altitude to be flown rule. If when following that rule you get under the clouds, then proceed via VFR lost comm procedures.

If you're approaching an MCA below the MCA, will ATC assign a new altitude, or do you need to request it?

Could be either. If not assigned, you should request it.

What is the difference between the OROCA and MIA? OROCA is published on NACO charts, correct?

Look in the Inst Procedures Handbook for Minimum IFR Altitude (MIA). Then look at the definition for Off Route Obstruction Clearance Altitude (OROCA).

The MIA can be an MEA or OROCA or MCA, etc.

Yes, OROCAs are on NACO charts.

FAR 91.175 says you can descend below the DH with the VASI in site. Does this apply to PAPI's also? Tricolor VASI's?

The VASI and PAPI are both Visual Glidepath Indicators. A PAPI applies.

Hope this helps!