Understanding the whole of IFR

Kritchlow said:
Nor can you circle if you are cleared for the LOC 15 approach unless you get permission.
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Absolutely you can! If you break out at circling mins and see the wind is not favorable for a landing or you can’t make the field from the MAP and are at or above circling mins you absolutely can circle to land without notifying ATC.
 
Grum.Man said:
What are straight in Mins, never heard of that. There are precision and non precision mind, LOC, LNAV, Circling, VOR, NDB, are all non precision approaches. ILS, VNAV, LPV are all precision approaches each having their own minimums. I’m not aware of any straight in minimums.
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There are approach minimums for straight in vs circle.
 
Grum.Man said:
Absolutely you can! If you break out at circling mins and see the wind is not favorable for a landing or you can’t make the field from the MAP and are at or above circling mins you absolutely can circle to land without notifying ATC.
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Perhaps at an uncontrolled field you could get away with such a thing.
 
Kritchlow said:
Perhaps at an uncontrolled field you could get away with such a thing.
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It happens all the time. Lots of rural airports only have an approach to one runway heading. If there is a brisk tail wind you almost have no choice but to circle to land.
 
LOC/DME-E is not a straight in approach by definition as it lists no runway number and has no straight-in minima.

There's a whole slew of requirements for the straight in approach. There is a approach angle (either the glide path or visual descent) that is dependent on the aircraft category. The lateral alignment with the runway depends on what you're using (VOR, LOC, etc..) for final course guidance.
 
Having so much fun exploring the difference between “straight in landing” and “straight in approach.” Awesome guys!
 
Different minimums for straight in. Jepp doesn’t use the “S”. As a default, if it’s not a circle it’s a straight in.
 
Kritchlow said:
Different minimums for straight in. Jepp doesn’t use the “S”. As a default, if it’s not a circle it’s a straight in.
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Ok I’ll give you that though it’s “straight ILS” mins. However the approach is still a straight in approach with circling to land minimums should you choose that.

Phraseology example: You are approaching an IAF very near to a required procedure turn heading. The controller may ask if you want the straight in or a procedure turn.
 
I get that there is a category of minimums on an approach called “straight” that can contain an ILS, LOC, NDB, and VOR. But that doesn’t define the approach, just the minimums. There are non straight in approaches that can have straight in mins just as there are straight in approaches with Circling mins.
 
Grum.Man said:
Ok I’ll give you that though it’s “straight ILS” mins. However the approach is still a straight in approach with circling to land minimums should you choose that.

Phraseology example: You are approaching an IAF very near to a required procedure turn heading. The controller may ask if you want the straight in or a procedure turn.
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Yes I understand what you are saying, but that’s different than a straight in approach vs circling approach.
 
Approaches aren't categorized as "Straight in". Only how you fly them. If you fly without a PT (or one is not provided), its a Straight-in approach.
 
This is a genuine question, not being a smart A. So if we call those approaches straight in because there is an S before the designation, what does it make an RNAV? There are no S’s before the LPV, LNAV/VNAV, LNAV, yet it also contains Circling mins.
 
No sorry, let me clarify:

Straight in approach = Flying an an approach without a procedure turn
Straight in minimums = Using the runway specific minimums on an approach. These are the lines of minima that begin S-ILS 6 or some such.

The terms are so similar, its easy to get them confused (as I did earlier in this thread).
 
George Mohr said:
No sorry, let me clarify:

Straight in approach = Flying an an approach without a procedure turn
Straight in minimums = Using the runway specific minimums on an approach. These are the lines of minima that being S-ILS 6 or some such.

The terms are so similar, its easy to get them confused (as I did earlier in this thread).
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Okay, I’ll roll with that. Is that what the OP meant I wonder??
 
George Mohr said:
I actually believe the OP was referring to the lack of Straight in minima. And the reason for that (I think!) is the 6 degree decent required from FAF to MAP. It would take a TERPS nerd to clarify this :D
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Ding ding ding we have a winner!:p
 
Greater than 400 ft / NM from FAF to threshold.
 
Grum.Man said:
Never heard of a bent ILS.
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Juneau Alaska had a bent ILS. The localizer was lined up crooked with the runway until the middle marker, then a right turn was required to line up with the runway. That approach went away in the mid-eighties...
 
A bent ILS is called an LDA. Juneau indeed has a LDA to runway 8 that's about ten degrees off. It has a glideslope and indeed has straight-in minima albeit quite high (over 3000' AGL).

DCA has had for decades a couple of LDAs. One like the LDA Y RWY 19 (formerly the ROSSLYN LDA, named after the Virginia city that it dumps you on) not only isn't aligned with the runway, but doesn't really get you that close to the runway when you hit the MDA on the glideslope, but still it has straight-in minima (not surprisingly the same as the circling minima). The LDA Z gives you a more direct shot into the runway, but it's still bent and the straing in minima have a slightly smaller visibility criteria if you're not in category C.
 
schmookeeg said:
I've flown planes that can make the chop n drop on that LOC 15 straight-in. :D I'd rather pop an eardrum than circle in that terrain personally.
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And, many pilots with good local knowledge and skillful with their airplane can safely do that. But, that cannot and should not be codified into TERPs design criteria. Special instrument approach procedures can relax the criteria based on an equivalent level of safety.
 
Wow, great discussions! Thank you to everyone who took part.

Here are brief synopsis of what I hoped would be (and was) discusses:

1-KASE-An approach title than includes a runway will have minimums for a straight in landing. If the title ends with a letter of the alphabet the approach will have circling minimae even though you may be able to land straight in. Circling mins are always going to be higher. The most common reason for an approach to have circling mins is the final approach course and runway are offset by 30 degrees or more. There are other reasons for an approach to have circling mins such as the case at KASE. There the terrain dictates a missed approach needs to be started from a position in space further from the runway and or a higher altitude to ensure a missed approach can be safely executed.

2-KFTG-The only way to know the alternate mins for an airport is to look them up. Notice the ILS approaches, as of this time, that are not authorized for use if the tower is closed. The feds explanation for this is the monitors are not tied into the reporting system so if tower goes down (scheduled or not!) the approaches are not available as an alternate.

Also, why do you think the non-precision approaches have higher than standard visibility and Cat D? Maybe not obvious if you do not know this area or have a chart available. KDIA (Denver International) is a stone throw away so the feds want to avoid interfering with operations there.

Was this something you would like to continue? Please give feedback, ask questions!
 
Circling mins are always going to be higher.
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Not true. In quite a few instances the straight-in and circling mimima are the same.
The only way to know the alternate mins for an airport is to look them up.
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The little A in the triangle on the plate is an indication that you need to look for non-standard alternate minums.
Also, why do you think the non-precision approaches have higher than standard visibility and Cat D?
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You're talking about the alternate minima? This is because the circling mimima are included in the determination. Cat D circling minima have higher visibilities because the circling area is bigger due to the higher airspeed.

KDIA (Denver International) is a stone throw away so the feds want to avoid interfering with operations there.
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What? That does not figure into computing the minima.
 
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Ok, flyingron let's take a look see.

I have not looked at every approach but in my experience when straight in is available the mins are lower. Can you identify a specific example to prove your point?

The symbol to which you refer is only on NOS charts. Jepp puts the alternate mins on the airport data page. The only way to know the alternate minimums is to look them up, parse this carefully and it should make sense. The NOS symbol should get your attention and serve as a flag that in order to know the actual minims you need to go look them up.

The KFTG part of this discussion has been about Alternate Mins. Approach designers consider many factors as part of their job. The proximity of other airports is most assuredly a huge consideration especially the missed approach segment.

Clear now?
 
Yeah, look at FTG's RNAV approaches. The straight-in LNAV has the same minima as the circling ones.
I wasn't disagreeing with you about looking them up. I was just indicating how FAA chart user knows they have to go elsewhere for non-standard minima. By the way, they haven't been NOS charts in years. The FAA took over the charting from NOS. The group was designated NACO, and later AeroNav Services. Yes, I like the way Jepp does it as well.

the proximity of other airports is most assuredly a huge consideration especially the missed approach segment.
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That's true for the design of the missed approach, but what does that have to do about alternate minima? The MISSED APPROACH segment doesn't enter into the calculation of alternate minima.


Here's a trivia question for you ForeFlight users: where do you find the alternate minimums in the app? (assuming you're using the FAA plate options).
 
NOS sorry about that, showing my age.

Looking at just expired US Terminal Procedures SW-1 KFTG page 261 (please Mr. Postman bring me my Jepps, soon!)
RNAV (GPS) RWY 17:
LPV DA 5691-3/4 200 (200-3/4)
LNAV/VNAV DA 5916-1 3/8 425 (500-1 1/2)
LNAV MDA 6000-1 509 (500-1)
Circling (just Cat A) 6000-1 485 (500-1)

Tired old brain here intertwining 121 and 91. Let's stick to 91 only. Although we discuss minimums as having ceiling and visibility requirements (or limits) visibility is controlling. But, under 91, if reported ceiling or visibility (or both) are below the mandated values we can still execute the approach and, if conditions allow, land.

So what is our limit? The DA or MDA because the lower we can descend the closer we will be to the runway and, if we can see the requisite items, and using normal maneuvering (spell check suggested manuring ha ;)), land. So I stand by my response. In thinking this over there are some semantic issues with the query and my response. I take full responsibility and accountability for them.

Does this work for you?
 
jonvcaples said:
Tired old brain here intertwining 121 and 91. Let's stick to 91 only. Although we discuss minimums as having ceiling and visibility requirements (or limits) visibility is controlling. But, under 91, if reported ceiling or visibility (or both) are below the mandated values we can still execute the approach and, if conditions allow, land.
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Where did 121 vs 91 come up in this discussion?

You are all over the map with these diatribes.
 
I even understand less what you're trying to say now than before. DA and MDA are just as controlling as the visibility. That number is divorced from ceilings as far as part 91 is concerned, as you say.

I don't know what "response" you're attempting to defend now. So much of what you said was wrong.
 
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