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-   -   Circle to land minimas (https://www.pprune.org/tech-log/514470-circle-land-minimas.html)

Valmont 12th May 2013 22:35

BOAC, Check your private messages.

PantLoad 13th May 2013 00:23

Please tell me....
 
Valmont,

Please tell me this guy was not U.S. trained. Please tell me....


Fly safe,


PantLoad

RAT 5 13th May 2013 07:58

Legitimate autority of the Captain still exists

Roulishollandais: In general, yes, but there's not legitimate authority to command and force you to do the wrong thing, especially crash the a/c. "I was only obeying orders." is not a defence. Are you suggesting that a captain has the authority to force an F/O to disobey SOP's or execute bad airmanship in an unsafe manner; or to do so himself without being opposed?

16024 13th May 2013 11:57

Spot on, with the caveat that the SOP's themselves probably say something along the lines of "The captain may take any action...blah,blah...safety".
Mine do.
And the captain disappearing into the boonies muttering about PANS CTL areas having nothing to do with terrain would be one such discussion point, if I were RHS (or jumpseat).

BOAC 13th May 2013 13:30

Here are 2 questions for those who understand circling:

Would you, unlike some here, circle off 19 at the meteor crater if there were published minima?

Is this ONE occasion where you could be justified in looking at the 01 plate to extract CTL minima?

SUPPLEMENTARY: What if joe-driver decided to fly the LPV 01 to a CTL at 8240'?

OK465 13th May 2013 16:33

Just when you thought it was safe to relax....

Said Captain is flying a Category C aircraft to scenic Lewiston, and planning to fly the RNAV (GPS) RWY 26 with the intent of circling to RWY 08. He notes the 26 LNAV MDA is 4480 and Category C circling minimum is 4720.

http://155.178.201.160/d-tpp/1305/00231R26.PDF

“Okay kid, for today’s lesson get out the RNAV (GPS) RWY 08 plate and we’ll use those minima to circle.”

Kid notes that the LNAV MDA is 4520 and Category C circling minimum is 4780, higher than the 26 plate. Kid points this out to the Captain.

http://155.178.201.160/d-tpp/1305/00231R8.PDF

“Okay kid, then get out the VOR RWY 08 plate and let’s take a look.”

Kid points out that the Category C S-8 VOR minimum is 4600 but Category C circling minimum is 4660, lower than the 26 plate.

http://155.178.201.160/d-tpp/1305/00231V8.PDF

Kid points out that there are no other IAPS to KLWT.

Captain scratches his head…ponders 4660, 4720 & 4780. ”Okay :mad: it kid, we’ll just fly the LPV straight-in to 08 and do some more circling training tomorrow.

BOAC 13th May 2013 16:57

My main breaker has tripped. What are they doing?

galaxy flyer 13th May 2013 16:57

OK465

I gotta ask, did you just happen upon KLWT or do you use for some mind-bending treatment of new IR students?

GF

BOAC 13th May 2013 17:05

Perhaps Valmont's Captain moonlights for the FAA?

OK465 13th May 2013 17:54

GF


I gotta ask, did you just happen upon KLWT or do you use for some mind-bending treatment of new IR students?
I was looking for somewhere nice to go on honeymoon with my new 24 year old bride.

BOAC 13th May 2013 18:15

I'd suggest a straight-in rather than a circle.......................:)

galaxy flyer 13th May 2013 19:59

And you, at 68, makes proud to be an American.

GF

FlightPathOBN 13th May 2013 20:16

shes 24 and you choose Lewiston? :rolleyes:

ZLV baby...ZLV... :ok:

aterpster 13th May 2013 21:18

OKC465:

So, why does the guy try to violate Part 97 rather than simply getting a clearance for the Runway 8 procedure?

aterpster 13th May 2013 21:19

FltPathOPN:

She is an avid hunter and fishergirl.

The mountains around Lewiston are stunning.

PappyJ 13th May 2013 21:24

Going back to the beginning of this thread, I suggest that the 'captain' in question was confused over the difference between a 'cirlcing' manuever and a 'side-step.'

Circling is simple -

It is common to fly to an airport where there is, let's say, an ILS approach but only to one runway. Suppose the winds don't favor that runway on this particular day. What to do? How about flying the ILS down to circling minimums, then circle to land on the opposite runway.

Just about every training manual, AIP, etc will state something to the effect of "...decend to the circling minimums on the profile view of the approach in use..."

Nowhere is it ever suggested to use the minimums for an approach that you DID NOT fly!

Whereas,

Sidestep Maneuver -

ATC may authorize a side-step maneuver to either one of two parallel runways .... followed by a straight-in landing on the adjacent runway. Aircraft executing a side-step maneuver will be cleared for a specified nonprecision approach and landing on the adjacent parallel runway.

For example, "Cleared ILS runway 7 left approach, side-step to runway 7 right." Pilots are expected to commence the side-step maneuver as soon as possible after the runway or runway environment is in sight. Landing minimums to the adjacent runway will be based on nonprecision criteria for the approach and therefore higher than the precision minimums to the primary runway, but will normally be lower than the published circling minimums.

Gotta say it; I agree with Pantload on this one.

aterpster 13th May 2013 21:37

Related to this thread, the FAA is finally implementing PANS-OPs-like circle to land areas. It will likely take 6, or more, years for this to factor through all the FAA IAPs:

http://ww1.jeppesen.com/documents/av...RPS_Chg_21.pdf

The first such IAPs were published on May 2.

aterpster 13th May 2013 23:11

OK465:


I was looking for somewhere nice to go on honeymoon with my new 24 year old bride.
My bad. I was thinking of Livingston, just east of Bozeman.

roulishollandais 14th May 2013 02:12

@RAT 5

Originally Posted by Valmont
I had to fly oneother rotation with this dude, you would'nt believe what he did to me today... I think the think the CP wont like what i'll have to say.

I don't contest the F/O has to be able to say NO in some cases (ie Flight KE801 GUAM 1997). But then HE will have to prove the Captain asked him to do something illicit or countrary to air safety. The Captain according to the Law does not need to prove he was right...

The result is in conflictual relation increasing flight after flight, and probably problems with the CP who will surely prefer to defend the Captain.
No doubt that Valmont told that storry to get help from us not to circle, but to manage relation improvement with "this Dude" and the "CP" and his future in the Airline.
But most Captains have learnt from experience and "do it simple".

BOAC 14th May 2013 06:55

I would like (reluctantly:O) to return from 24 yr old brides and what to do with them to circling minima and in particular post #47.

These figures contradict everything I have ever understood or been taught about circling. Can anyone who understands this US system explain the varying altitudes?

aterpster 14th May 2013 12:31

BOAC:


These figures contradict everything I have ever understood or been taught about circling. Can anyone who understands this US system explain the varying altitudes?
I believe that's about TAS increasing with the elevation of the airport.

But, here are the three pages of FAA TERPs criteria for your assessment:

http://tinyurl.com/celrhbp

BOAC 14th May 2013 13:29

Thanks for the drop, but that doesn't really answer the question - and the 'airport elevation' does not change!

The only (drop) bit (Section 6 - 260 I cannot follow is
"and the evaluation of the final segment delivering the aircraft to the circling area. Also see Vol. 1, chapter 3, paragraph 3.2.1b." whatever that means - that is the only factor I can see that might produce different numbers - but does not at all other airports we know of.

Is there anyone around who produces charts who can have a crack at this puzzle?

aterpster 14th May 2013 14:26

BOAC:

A link to the entire order:

http://www.faa.gov/documentLibrary/m..._Chgs_1-25.pdf

FlightPathOBN 14th May 2013 15:42

terpster,

The FAA madness continues.... Change 26

perhaps someday, they will make the entire 8260 digital, not photocopied, so it can be searched....

OT... years ago, I saw a draft 8260.52A, that was supposed to align .52 with ICAO...have you seen that around somewhere and who might be working on it, if anyone??

BOAC 14th May 2013 15:52

FPOBN - I take it you have no explanation for the 3 different CMs?

swh 14th May 2013 17:04

BOAC,

It might have to do with

"5.4.4 OCA/H for visual manoeuvring (circling)
The OCA/H for visual manoeuvring (circling) shall provide the minimum obstacle clearance (MOC) over the highest obstacle in the visual manoeuvring (circling) area as specified in Table I-4-7-3 of Chapter 7. It shall also be:
a) above the lower limits (also specified in Table I-4-7-3); and
b) not less than the OCA/H calculated for the instrument approach procedure which leads to the circling manoeuvre. See Chapter 7, “ Visual manoeuvring (circling) area”."

With the different approaches they have different "OCA/H calculated for the instrument approach procedure which leads to the circling manoeuvre" because of the different splays due to the accuracy of each approach design final segments.

BOAC 14th May 2013 17:12

swh - we looked at that in post#15 for Monterey. I don't see the approach minima being the restriction on these approaches from post #47?

galaxy flyer 14th May 2013 23:35

A nymphomaniac who is turned on by Oklahomans that post on Pprune, I'll bet.

GF

felixthecat 15th May 2013 04:25

I know its a bit radical and out left field but hey why not just round up the highest to the next 100' i.e. 4800 and fly that? I am an old simple pilot and believe in the KISS principle …. Keep It Simple Stupid. You only have so many heartbeats don't use them up so fast.

BOAC 15th May 2013 07:05

Careful, OK - you'll get Slasher here PDQ with those sort of posts.....................:)

Back to the CTL - it is interesting that 2 of the 3 CMs breach EU-OPS minimum MDH for Cat C circling (600').

I think all we can assume is that someone might have been a bit too far into the Jack Daniels when the charts were drawn?

How will one distinguish the 'revised' (PANSOPS) CM from the 'old' (TERPS) CM on an FAA chart?

RAT 5 15th May 2013 08:48

In flight you have to obey to the Captain

Harping back on this topic in the thread I would draw people's attention to the thread on the Bali B737 crash. It would seem the captain followed my earlier scenario of "keep going.......oops, wrong again."

What happened to F/O's having a self preservation button somewhere in the area of the TOGA button; or at least a loud voice?

galaxy flyer 15th May 2013 13:13


What happened to F/O's having a self preservation button somewhere in the area of the TOGA button; or at least a loud voice?
One guess, dirigisme, French for "I have control"

GF

aterpster 17th May 2013 14:11

BOAC:


Back to the CTL - it is interesting that 2 of the 3 CMs breach EU-OPS minimum MDH for Cat C circling (600').
FAA uses TERPs and only TERPs.


I think all we can assume is that someone might have been a bit too far into the Jack Daniels when the charts were drawn?
I don't assume that so please don't speak on my behalf.


How will one distinguish the 'revised' (PANSOPS) CM from the 'old' (TERPS) CM on an FAA chart?
Different speeds as it always has been.

FlightPathOBN 17th May 2013 14:51

Pilots should be aware that there are significant differences in obstacle clearance criteria between procedures designed in accordance with ICAO PANS-OPS and US TERPS. This is especially true in respect of Circling Approaches where the assumed radius of turn and minimum obstacle clearance are markedly different

From May 2, 2013, the FAA started publishing new instrument approach plates that include an enlarged segment of airspace to protect aircraft during circling approaches. The new airspace also offers pilots additional obstacle clearance while considering their MSL altitude above the MDA, which affects true airspeed. The boundaries of protected airspace for circling approaches are defined by arcs drawn from the threshold of each runway at an airport. The larger the aircraft, the larger the arc. Previous versions of the FAA’s terminal instrument procedures (Terps) used a radius of 1.7 nm from the end of the runway for a Category C aircraft such as a Hawker 800. Under the new criteria that radius will increase by 65 percent, to 2.7 nm. Chart providers U.S. Terminal Procedures and Jeppesen both plan to use new chart symbology to identify the updated approaches. The government plates will show an inverse “C” in a black box in the approach minimums area of the plate, while Jeppesen will use a “C” inside a black diamond. Charts without the new designation will continue to be guided by the old, smaller-radii criteria.

Jepp Charts:
http://www.skybrary.aero/images/JepAC.jpg

edit: Govt Charts
http://www.nbaa.org/ops/airspace/iss...nima-chart.jpg

Circling Approach - difference between ICAO PANS-OPS and US TERPS

BOAC 17th May 2013 15:42

"The government plates will show an inverse “C” in a black box in the approach minimums area of the plate,". Thanks FPOBN

The TERPS/PANSOPS thing has been done to death here so many times it really does not need doing again! I was hoping our 'charters' here might be able to offer an explanation for the 3 different circling minima, but it appears they are flummoxed too.

Let's try a really simple question for someone:
Is it safe at Lewiston to fly the VOR 08 to circle at 4660' which is 120' lower than the safe circling from an LNAV approach to 08 and lower than the circle from the 26 approach - and why? I thought circling areas were fixed in geometry on airfield/runway characteristics so should not change, (barring approach minima issues, but here both less than 4660'). Presumably the circling area must change, but why?

FlightPathOBN 17th May 2013 16:01

The geometry is not fixed, it varies with altitude and aircraft CAT...

http://operationsbasednavigation.com....-17-08.51.jpg

CAT A and CAT B are close, so they can have one circling MDA, while CAT C is much larger, and CAT D even larger differences in radii....

edit:
Here is the proposed change to the charts on the CAT Radius.

http://operationsbasednavigation.com...8807195401.jpg


RNP charts dont have to deal with this! :E

BOAC 17th May 2013 16:15


The geometry is not fixed, it varies with altitude and aircraft CAT...
- Lewiston - same airfield elevation, Cat C same Category??

I'll try it more simply - can circling area geometry vary for the same airport and same aircraft cat - and how?

EDIT:

RNP charts dont have to deal with this!
- why? Is circling abandoned with RNP charts?

EDIT 2: Shouldn't the Cat C and D be 3 and 4nm?

FlightPathOBN 17th May 2013 16:54


same airfield elevation, Cat C same Category
not airfield elevation...MDA of circling.

BOAC 17th May 2013 17:32

We are going around in circles here! :) Original question - how can you have 3 different CMs for the same airfield, same a/c Cat?

Q1- can circling area geometry vary for the same airport and same aircraft cat - and how?

a) I assume you take the obstacles within the altitude adjusted radius and add 300'?
b) If this pushes the CM into the next altitude band, you redo it at the new radius and iterate if required?

There we are - 1 CM surely?

Q2 - RNP/CTL?

FlightPathOBN 17th May 2013 18:55


EDIT 2: Shouldn't the Cat C and D be 3 and 4nm?
Good comment, add it to living with the FAA....

RNP are coded procedures, there is no circling...you are on it or not.


I dont know why there are the differences at Lewiston, and I really dont want to get into laying out the circling diagram...but I will leave you with this figure 2 to ponder, consider the different variables, (and really be concerned about how many mistakes can be found on charts or in the navdatabase)

http://operationsbasednavigation.com....-17-11.47.jpg


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