Airline Pilot Central Forums - Inbound Question

Airline Pilot Central Forums (https://www.airlinepilotforums.com/)

- Technical (https://www.airlinepilotforums.com/technical/)

- - Inbound Question (https://www.airlinepilotforums.com/technical/61120-inbound-question.html)

Is it a TERPS or PANS-OPS procedure? It would make a difference if coming from the south.

GF

Quote:

Originally Posted by wizepilot (Post 1031831)

That 1400' is only good if you are ON the radial or loc inbound within 10nm of TAM. Look at the MSA. If they told you to maintain 3,000, cleared for the approach, then stay there until at least you complete the procedure turn, the loc comes alive and you are within 10nm of TAM. Then you can descend to 1400. I know it's a short distance. If you go down to 1400 on your way out, then turn off the course to do the procedure turn, you may not know what you might run into.

Quote:

Originally Posted by wizepilot (Post 1031841)

Let me requalify my previous post. If you are within 15DME or 10DME TAM (same thing) then you can go down to 1400. Once the loc comes alive, and you are within the proper distance, you are terrain protected. I had to look at that plate again! Carry on.;)

I think you were correcting yourself, but just to clarify you can descend to 1400ft if you are established on the TAM 317 radial. Look at the profile. It shows a descent line to 1400ft with a 317 above the line. It also says 10NM of D5.0 TAM or D4.2 ITAM. Just stay with in 15 miles of the TAM VOR, as the 10 mi protection ring is centered around the TAM 5 DME point.

Quote:

Originally Posted by johnso29 (Post 1032173)

Yep, makes sense... 1,400' after TAM and "established" on the 317 radial.

Now my other question refers to "established." We have been training within 1 dot is established but I cannot find where this came from.

Within "1 Dot" comes from ICAO's definition of "on course"; or +\- 5 degrees for NDB. Check PANS-OPS Doc 8168, Vol 1. Technically, the FAA's position is that "on course" is needle centered, 1 dot off course and intercepting is technique to lead the intercept of the course, not "on course".

GF

Quote:

Originally Posted by galaxy flyer (Post 1032328)

Within "1 Dot" comes from ICAO's definition of "on course"; or +\- 5 degrees for NDB. Check PANS-OPS Doc 8168, Vol 1. Technically, the FAA's position is that "on course" is needle centered, 1 dot off course and intercepting is technique to lead the intercept of the course, not "on course".

GF

GF -

While looking up some of the things discussed today with a fellow worker he pointed out to me the passage in the 'Instrument Procedures Handbook' which defined 'on course' as [1 dot]. I wrote down the reference manual and page number but don't have it with me now. That same paragraph also mentions the +/- 5 deg of oncourse bearing for the NDB as you mention above. Maybe this is another area where the FAA has adopted ICAO standards of recent?

USMCFLYR

Never flown into Mexico, but why is there no IAF labeled? In the U.S., could you even legally begin this approach without radar vectors?

The more recent version of the chart has a multitude of IAFs.

GF

I read in the Jeppesen instrument procedures guide that half-scale or less is established.

Thefly

Right out of ICAO Doc 8168, that is

GF

To the OP,

I think galaxy flyer's answers are best (though I haven't been based in the US in a few years.)

On another note, funny how some other posters were ridiculing you and it turns out that theirs were not the best answers. You'll find this a common theme throughout your career. Just keep asking questions and reading on your own to gain knowledge despite the detractors.