Missed Approach Text

[midlifeflyer]

GPS is not required if there is Radar.

Right. As we said before, there multiple variations on the theme. That's the real point. We can learn (a) this one approach by rote or (b) here's something we can apply when looking at approaches, including this one. Personally, I rarely care that much about (a).

Yet another variation is at my home base. Two GPS required restrictions. One GPS or RADAR for procedure entry, but GPS is required anyway.

 

[midlifeflyer]

What I think is lost on pilots is that conventional ILS missed approach criteria are not used for ILS 17R except for the Y ILS and Y LOC. It's RNAV-1, which requires all the checks and balances by the RNAV avionics.

Agree completely. That's why the lesson is greater than this one approach.

 

[John Collins]

Keep in mind this is an RNP approach even though it is an ILS, which means GPS and approved IFR RNAV and the procedure will be in the database.

Wally, I think it is a conventional ILS or LOC approach, but requires RNP APCH - GPS for entry to the procedure and missed approach. It is strange that DME is also required. Also, I don't see any indication that RF is also required if using either HOBOA or KLOCK IAF. I would have expected it noted on either the HOBOA or KLOCK IAF routes or in the equipment/PBN box or notes. The procedure is included in my GTN 750Xi database (ILS Z and LOC Z as two procedure versions), but not in the Jeppesen GNS 530W database. Both the GTN 750Xi and the GNS 530W meet the RNP APPCH - GPS requirement, but the latter is not approved for RF. Your thoughts?

 

[John Collins]

Right. As we said before, there multiple variations on the theme. That's the real point. We can learn (a) this one approach by rote or (b) here's something we can apply when looking at approaches, including this one. Personally, I rarely care that much about (a).

Yet another variation is at my home base. Two GPS required restrictions. One GPS or RADAR for procedure entry, but GPS is required anyway.

View attachment 113232

Current charting standards will change the RNAV - 1 GPS required to RNP APCH - GPS required. The difference is that any GPS that meets the RNP APCH PBN spec will do, verses one that is RNAV - 1, which many do not meet, example the KLN 94. No reason the KLN 94 can't be used as it meets the RNP APCH but not RNAV 1.

 

[midlifeflyer]

Current charting standards will change the RNAV - 1 GPS required to RNP APCH - GPS required. The difference is that any GPS that meets the RNP APCH PBN spec will do, verses one that is RNAV - 1, which many do not meet, example the KLN 94. No reason the KLN 94 can't be used as it meets the RNP APCH but not RNAV 1.

Can you explain that a bit more, John? How can a box which meets approach scaling criteria not meet enroute or terminal criteria?

 

[aterpster]

Wally, I think it is a conventional ILS or LOC approach, but requires RNP APCH - GPS for entry to the procedure and missed approach. It is strange that DME is also required. Also, I don't see any indication that RF is also required if using either HOBOA or KLOCK IAF. I would have expected it noted on either the HOBOA or KLOCK IAF routes or in the equipment/PBN box or notes. The procedure is included in my GTN 750Xi database (ILS Z and LOC Z as two procedure versions), but not in the Jeppesen GNS 530W database. Both the GTN 750Xi and the GNS 530W meet the RNP APPCH - GPS requirement, but the latter is not approved for RF. Your thoughts?

According to the IFP Gateway NDBR for that IAP, RF required was removed because, the explanations state it is no longer required by the 8260.19I. As to the DME, that can only be QC issue.

 

[jimhorner]

The thing that I noticed about this approach is the instruction to turn right (tr) from a heading of 183° to 127°. Highlighted in the picture below. That seems a bit counterintuitive to me. Do they really want the pilot to make a 304° turn to the right at USINE instead of a 56° turn to the left? Maybe I'm misunderstanding what "tr" means?

 

[Sluggo63]

Maybe I'm misunderstanding what "tr" means?

View attachment 113238

TRack

 

[John Collins]

Can you explain that a bit more, John? How can a box which meets approach scaling criteria not meet enroute or terminal criteria?

The RNAV 1 PBN specification eliminates many of the first and second generation GPS navigators. RNAV 1 is needed to fly RNAV SIDs and STARs. AC 90-100A requires the support for CF (Course to Fix) path terminators in the database. If you look at the AC 90-100A Compliance matrix https://www.faa.gov/about/office_or...fs/afs400/afs410/media/AC90-100compliance.pdf you will see that most of the older GPS systems including the KLN94 don't support the CF path terminator in the database, so are not approved to use RNAV 1 based procedures. You also won't find any RNAV SIDs or STARs in the database for these older units, just conventional SIDs and STARs. They do however support RNP APCH which includes RNAV 1 segments in the terminal area (within 30 NM of the departure/destination). So the PBN RNAV 1 specification excludes these older GPS navigators, but the RNP APCH includes them without needing to support the CF path terminator in the database. CF Path terminator legs are used in some RNAV SIDs, but not in RNAV (GPS) approaches, so the RNP APCH PBN specification is more inclusive when used in an approach procedure. These procedures used to be GPS required, that morphed to RNAV 1 GPS required, and now to RNP APCH - GPS. See the foot notes in the compliance document, page 2. I hope that this is as clear as mud.

 

[jimhorner]

TRack

Ahhh! That makes more sense. Thanks for the clarification. Knew I was missing something.

I use "tr" in my shorthand when getting a "turn right" instruction in a clearance. So that's why I interpreted it that way, I guess. I've gotten clearances from Palo Alto in the past that said something like:

Cleared to abc via turn right heading 060 within 1 mile of the airport, radar vectors San Jose, Victor 334 Sunol ...

I'll shorthand that as:

ABC tr 060 wi 1 mi RV SJC V334 SUNOL ...

Guess I'd internalized tr as "turn right" instead of Track. My bad...

 

[Palmpilot]

The RNAV 1 PBN specification eliminates many of the first and second generation GPS navigators. RNAV 1 is needed to fly RNAV SIDs and STARs. AC 90-100A requires the support for CF (Course to Fix) path terminators in the database. If you look at the AC 90-100A Compliance matrix https://www.faa.gov/about/office_or...fs/afs400/afs410/media/AC90-100compliance.pdf you will see that most of the older GPS systems including the KLN94 don't support the CF path terminator in the database, so are not approved to use RNAV 1 based procedures. You also won't find any RNAV SIDs or STARs in the database for these older units, just conventional SIDs and STARs. They do however support RNP APCH which includes RNAV 1 segments in the terminal area (within 30 NM of the departure/destination). So the PBN RNAV 1 specification excludes these older GPS navigators, but the RNP APCH includes them without needing to support the CF path terminator in the database. CF Path terminator legs are used in some RNAV SIDs, but not in RNAV (GPS) approaches, so the RNP APCH PBN specification is more inclusive when used in an approach procedure. These procedures used to be GPS required, that morphed to RNAV 1 GPS required, and now to RNP APCH - GPS. See the foot notes in the compliance document, page 2. I hope that this is as clear as mud.

Given the large number of rental planes that have a KLN94 installed, good to know, thanks!

 

[midlifeflyer]

The RNAV 1 PBN specification eliminates many of the first and second generation GPS navigators. RNAV 1 is needed to fly RNAV SIDs and STARs. AC 90-100A requires the support for CF (Course to Fix) path terminators in the database. If you look at the AC 90-100A Compliance matrix https://www.faa.gov/about/office_or...fs/afs400/afs410/media/AC90-100compliance.pdf you will see that most of the older GPS systems including the KLN94 don't support the CF path terminator in the database, so are not approved to use RNAV 1 based procedures. You also won't find any RNAV SIDs or STARs in the database for these older units, just conventional SIDs and STARs. They do however support RNP APCH which includes RNAV 1 segments in the terminal area (within 30 NM of the departure/destination). So the PBN RNAV 1 specification excludes these older GPS navigators, but the RNP APCH includes them without needing to support the CF path terminator in the database. CF Path terminator legs are used in some RNAV SIDs, but not in RNAV (GPS) approaches, so the RNP APCH PBN specification is more inclusive when used in an approach procedure. These procedures used to be GPS required, that morphed to RNAV 1 GPS required, and now to RNP APCH - GPS. See the foot notes in the compliance document, page 2. I hope that this is as clear as mud.

I'm sorry to say that made sense to me