What is a "Published segment of an approach"

[Bernoulli]

Question for you guys...When cleared for the approach you can only begin your descent below your last assigned altitude once you are on a published segment of the approach. My qusestion is: what constitutes a "published segment of an approach?" One of my friends says that a "published segment of an approach" only begins once you have reached an IAF. Now most approach plates have feeder routes that lead up to IAF's and they have altitudes listed on them... So are you alowed to descend to those feeder rout altitudes prior to an IAF? hey are published... and they are on the approach plate.

 

[Flechas]

If there is a inimum altitude published for a feeder route (or MEA), and you are clearedfor the approach, you can begin your descent if cleared for the approach. You don't have to wait untill the IAF.

 

[Bernoulli]

Just for the record... I agree with my friend. An approach BEGINS at the IAF, therefore a "published segment of an approach" must be within the IAF. I am throwing this question out there because I think it can easily be misconstrued and I have not been able to find a clear answer in any of my books. Thanks for any comment in advance.

 

[AV8OR]

Technically, your ability to descend without further clearance, comes once you are "cleared for the approach" AND "established".

"Cleared for he approach" - In order for ATC to clear you for that approach, ATC has a criteria that you either be established on a feeder route like you mentioned or that you meet the criteria for shooting that type of approach, like having the traffic ahead, or the runway in sight for a visual, etc. In instrument conditions, you are either on a vector or on a route, That's all there is. And routes are published. Therefore, if you are "established" on a feeder route, you are good to descend to the MEA for the route, once "cleared for the approach". So there's half the key.

"Established" - On a visual, you are on a visually established route, by either following traffic or following established AIM procedures for proceding to the runway. In IMC, you must be on the published track to be established. ATC can't legally give you a "cleared for the approach" call without either giving you a vecor for intercept, (to get you established), or insuring that you have met any other criteria make sure you ARE established. That's the other half of the key.

Bottom line, once "cleared" AND "established", whether on a feeder, or inside the IAF you are good to descend.

Hopefully that's what you were looking for.

Good question by the way.

 

[Bernoulli]

OK... I just read in 5-4-7 of the AIM and I'm totally wrong. Here's what it says:

"The pilot shall....(blah blah blah)...maintain the last assigned altitude unless a different altitude is assigned by ATC, or until the aircraft is established on a segment of a published route or IAP (instrument approach procedure). After the aircraft is so established, published altitudes apply to descent within each succeeding route or approach segment unless a different altitude is assigned by ATC.

So basically if you are cleared for an approach and you are outside of an IAF but you are on a feeder route that is published on your approach plate, you can descend to that feeder route's altitude.

Any further comments to clarify this are much appreciated

 

[Singlecoil]

It isn't just feeder routes, but airways this applies to as well. You can be 100 miles from your destination and you might hear, "Cessna 123C, cleared approach XYZ airport". You now own all the airspace from your current assigned altitude down to and including the MEA, as well as any feeder route that might be handy. This example would be for a pretty remote area but they are out there (Alaska, Montana, Idaho, etc). The only caveat is that once you report leaving an assigned altitude, you would need a clearance if you want to go back up to it for some reason.

 

[Vector4fun]

This example would be for a pretty remote area but they are out there (Alaska, Montana, Idaho, etc). The only caveat is that once you report leaving an assigned altitude, you would need a clearance if you want to go back up to it for some reason.

I think you're describing a Cruise Clearance there. Those are fun to issue for amusement sometimes, if it's slow. You can almost see the [?????]s next to the aircraft's tag on the radar....

 

[Singlecoil]

I actually started writing 'cruise' but changed it to keep things simple. I've heard it put both ways. Sometimes they'll say "cleared approch" without specifying which approach. I'm not sure if they are supposed to do that but it happens.

Extra credit: What if you are dropping off mail in little podunk airports, the controller is tired of talking to you, and s(he) says, "Cessna 123C, cruise 6000 through XYZ airport to LMN airport."

You are on an airway with an MEA of 5000 and a MOCA of 4000 that terminates at a VOR which is an IAF for XYZ. What can you do with that clearance?

 

[Bernoulli]

Extra credit: What if you are dropping off mail in little podunk airports, the controller is tired of talking to you, and s(he) says, "Cessna 123C, cruise 6000 through XYZ airport to LMN airport."

You are on an airway with an MEA of 5000 and a MOCA of 4000 that terminates at a VOR which is an IAF for XYZ. What can you do with that clearance?

A cruise clearance clears you for three things.
1. A block of altitude between What ATC says (6,000) and the MEA (5,000)... so in your example you can fly between 6,000 and 5,000 feet when you want without telling ATC. If you do rport to ATC that you are leaving an altitude you can not go back to that altitude... so keep your options open and your lip butoned.
2. Cleared direct to your destination
3. Cleared for any approach to the airport.

So to answer your bonus question, you can fly between 6,000 and 5,000 until you reach the IAF and then you are expected to shoot the approach.

 

[Singlecoil]

Your answer is correct except for the cleared direct to destination airport. You can't do that automatically under a cruise clearance. What about after you get to XYZ airport? Your clearance was to cruise through XYZ to LMN airport?

 

[Bernoulli]

Your answer is correct except for the cleared direct to destination airport. You can't do that automatically under a cruise clearance. What about after you get to XYZ airport? Your clearance was to cruise through XYZ to LMN airport?

Yeah... Sorry... I meant that a cruise clearance clears you to your destination airport (but not direct to your destination airport).

As far as cruising through XYZ airport to LMN... I would assume that you can fly between 6,000 and 5,000 feet up to XYZ and if the airway stops there and you need to get from XYZ to an IAF for LMN and (now I'm assuming there is no airway to LMN from XYZ) you can then fly a block of airspace from 6,000 to the as low as 1,000 feet above flat terrain and 2,000 feet above mountainous terrain. I'd prbably simply look at the OROCA (Grid MORA) and fly between 6,000 and the OROCA until reaching LMN's IAF... Then I'd commence the approach.

 

[sqwkvfr]

When you get to xyz airport are you within 25MN of LNM airport? If so, I might be inclined to adhere to the MSAs specified on the approach plate until reaching the IAF or a feeder route.

No?

 

[Bernoulli]

When you get to xyz airport are you within 25MN of LNM airport? If so, I might be inclined to adhere to the MSAs specified on the approach plate until reaching the IAF or a feeder route.

No?

Very good point. I would agree with you there.

 

[Green Banana]

White Devil (aka. Singelcoil) is correct about being "Cleared Approch" It happens alot where I fly. It means you can fly whatever approch you want, what ever published IAP route you want. You can also decend to the MEA of the airway you are on at that time!

AIM 5-4-7
d. At times ATC may not specify a particular approach procedure in the clearance, but will state "CLEARED APPROACH." Such clearance indicates that the pilot may execute any one of the authorized IAPs for that airport. This clearance does not constitute approval for the pilot to execute a contact approach or a visual approach.

 

[TonyC]

What is a "Published segment of an approach"
Question for you guys...When cleared for the approach you can only begin your descent below your last assigned altitude once you are on a published segment of the approach. My qusestion is: what constitutes a "published segment of an approach?" One of my friends says that a "published segment of an approach" only begins once you have reached an IAF. Now most approach plates have feeder routes that lead up to IAF's and they have altitudes listed on them... So are you alowed to descend to those feeder rout altitudes prior to an IAF? hey are published... and they are on the approach plate.

If the answers you get are confusing, it's probably because you've asked two distinctly different questions.

1 - What is a "Published segment of an approach"?

2 - ... are you allowed to descend to those feeder rout[e] altitudes prior to an IAF?


You seem to have already answered the first question. The initial segment of an approach begins at an Initial Approach Fix. Sounds like your friend is correct. If you agreed with your friend, I'm assuming you wouldn't have asked the question here, so it sounds like you owe your friend a cold beverage.


The answer to the second question is, "it depends." It would depend on the clearance received. The feeder route is just that - - a feeder route. It is NOT a portion of the approach procedure. If your clearance were, "Maintain X thousand until 'ABC' (ABC being the IAF), cleared YYYYY Runway ZZ Approach", then you could not descend, even if you were on a published Feeder Routing with published course, distance, and altitude information.

It is my understanding that "Maintain X thousand until established on the approach..." would mean exactly the same as above. It is also my understanding that others here disagree with that interpretation. Fortunately, I don't think that distinction is the focus of your attention, and I haven't seen that addressed in this thread so far.

If your clearance is "You're cleared the YYYYY Runway ZZ Approach" you may descend on a feeder routing.

Sounds like your friend might owe you a cold beverage, too.



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