RNP SID with RF leg

[divinehover]

HK has new RNP 1 SID's that use an RF Leg. Are these to be considered -AR (SAAAR for you Yanks) procedures because of the RF Leg or is it merely an issue of equipage? Our A340's can easily fly an RNP 1 SID with an RF Leg but the type has not been certified for RNP-AR operations.

Is this a bit of a grey area wrt ICAO guidance or am I over complicating the issue?

In summery: Can a non-RNP-AR certified aircraft, capable of flying RF Legs legally fly an RNP 1 SID with a RF Leg in the procedure?

[rennaps]

I think the answer is yes.
An RF leg in any instrument procedure does not necessarily make it an RNP-AR procedure.
However RNP-AR procedures can by definition include an RF leg.

[Ollie Onion]

If it is intended as an RNP-AR the approach chart should be annotated as such.

[aterpster]

divinehover:

HK has new RNP 1 SID's that use an RF Leg. Are these to be considered -AR (SAAAR for you Yanks) procedures because of the RF Leg or is it merely an issue of equipage? Our A340's can easily fly an RNP 1 SID with an RF Leg but the type has not been certified for RNP-AR operations.

We Yanks converted from SAAAR to AR about 2 years ago.

Which departures at VHHH have RF legs? I can't locate them.

[divinehover]

TITAN 1E/F, SKATE 1E/F, RASSE 1E/F etc

See HK AIP A19/11

[aterpster]

divineholder:

TITAN 1E/F, SKATE 1E/F, RASSE 1E/F etc

See HK AIP A19/11

I am looking at the current Jeppesen charts and a current database. The turn at ROVER appears to be a flyby waypoint to a TF leg. There is no mention of an RF leg.

I'll try the HK AIP although it is painfully slow here.

[aterpster]

Only AIPs on HK site are the current one 07/12
and archive 06/12 and 05/12.

The current one fails to complete download. Poor connection.

[divinehover]

I also struggled but got it eventually. I suspect it might only be a trial procedure for approved operators

[FlightPathOBN]

http://operationsbasednavigation.com/wordpress/wp-content/uploads/2012/07/SC-09.jpg

http://operationsbasednavigation.com/wordpress/wp-content/uploads/2012/07/SC-10-e1341945005553.jpg

There is a coded RF leg, so you would have to have this in your database to call it up. They have the radial point, but dont name it.

The other legs are just fly by turns...sortof unusual, the DER should be a flyby waypoint as well, a few of the terminators are goofed up as well....

[FlightPathOBN]

Can a non-RNP-AR certified aircraft, capable of flying RF Legs legally fly an RNP 1 SID with a RF Leg in the procedure?

I believe the answer to your question is no. This procedure would have to be in your navdatabase, and since it actually does have an RF turn, the ac would have to have the the required equipage and certification, as well as crew authorization to use this...

I really dont understand the mystery behind turns, other than the containment areas for AR, follow the 2X RNP rule, and while this is RNP 1.0, AR is AR....

[alphacentauri]

Maybe a little off topic.....but

Can you fly a RNP-AR procedure by hand? or do they have to be flown on autopilot?

If so, where is the reference? I had assumed I would find the answer in the ICAO PBN, but alas no luck....unless I didn't look hard enough (distinct possibility)

Cheers Alpha:ok:

[divinehover]

FlightPathOBn

The A340 is certified for RNP 1 operations for SID's and STAR's. The A340 equipped with Honeywell FMS 2 can fly an RF Leg if it is coded in the Nav DB (obviously). My company's Ops Spec allows for RNP 1 operations. This procedure doesn't state that it is an -AR procedure, it just mentions equipage.

If this is an -AR procedure then why isn't stated as so like all other -AR procedures in the text box?

[rennaps]

The regulation is in ICAO Document 9905 "Required Navigation Performance Authorization Required (RNP AR) Procedure Design Manual"
Chapter 2 RNP AR APPROACH PROCEDURE DESIGN
2.3 STANDARD CONDITIONS
b) procedure is flown using flight director or autopilot;

[alphacentauri]

Rennaps, Thanks.

I had read that document....but if it is flown on a flight director, doesn't that mean the procedure is being flown by hand?

[divinehover]

I am pretty sure that you can fly it by hand using the FD. The requirement is to maintain RNP X. There is no reason why you can't do this using just the FD. In fact in my RNP-AR training at Airbus we did some hand flown -AR work to demonstrate how accurately you could fly on the FD's alone. Autopilot use would obviously be the first option in marginal wx conditions. On a nice VMC day why not hand fly. Just don't bust the RNP requirement.

[rennaps]

I wouldn't like to fly an RNP 0.1 AR approach procedure by hand.
You would just have to cough to be outside the protection area. :)
Also can one fly an RF leg by hand?

[aterpster]

rennaps:

I wouldn't like to fly an RNP 0.1 AR approach procedure by hand.
You would just have to cough to be outside the protection area. http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/smile.gif
Also can one fly an RF leg by hand?

In the U.S. at least most operators permit an RNP AR 0.30 IAP to be hand-flown but using the flight director. Below 0.30, autoflight is required.

Presumably, a departure with an RF leg should be not less than RNP 1.0, which would be quite easy to hand fly with the flight director.

[FlightPathOBN]

There is certainly much room for improvement on the part of the regulator for this procedure. Certainly not a standard plate or terminology, leading to the confusion. Some of the waypoint altitude data is conflicting.

With a RF turn, it is defined as AR. I am not sure how HK is with RNP certification, if they follow ICAO, or have their own version with exemptions...

As it is RNP 1, and the turn radius is large enough, there shouldnt be any reason one cant fly it with the FD and stay within containment....or why one wouldnt just let the box fly this, if able.
I would note the first waypoints (PORPA/ROVER) have an altitude of 5000 at 5nm....

If what terpster says is correct, the procedure is not in the Jepp database, then you go no where fast...

BTW...for reference, there is no RNP departure criteria....FAA or ICAO.....

[reynoldsno1]

The coding provided by the State is not necessarily the coding in the FMS...
As has been pointed out, there are no design criteria for RNP departures in the public domain, but that does not preclude customised procedures being developed and approved (e.g. GE/Naverus developments).

These procedures appear to require specific approval from the Hong Kong CAD - good luck :rolleyes:

[FlightPathOBN]

Naverus did custom RNP departures?!?!?!

Who'd 'ave thought.....

Aside from that, the point was that there is NO criteria for Public RNP departures, therefore, this is not a public procedure for just anyone to have access to...

unfortunate, but until ICAO gets it together, you are gonna have to pay for these..

[9.G]

ICAO DOC 8168 p 520 specifies RNAV RNP DEP criterion. Jeppesen chart states that this departure is available to RNP 1 equipped and approved operator. I don't see any dilemma here. If a operator has the approval then there's nothing precluding from using that departure. :ok:

[aterpster]

9.G

ICAO DOC 8168 p 520 specifies RNAV RNP DEP criterion. Jeppesen chart states that this departure is available to RNP 1 equipped and approved operator. I don't see any dilemma here. If a operator has the approval then there's nothing precluding from using that departure. http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/thumbs.gif

Jeppesen will not publish public (non AR) procedures with RF legs until such time that the FAA (and presumably other states as well) authorize the public use of RF legs in non-AR IAPs.

I was able to download all of the HKG SIDs today. All the VHHH SIDs that Jeppesen publishes in their public subscription do not have RF legs.

The VHHH SIDs that RF legs are as follows:

ATENA 1E and 1F
LOGAN 1E and 1F
RASSE 1E and 1F
SKATE 1E and 1F
TITAN 1E and 1F

These are not in the Jepp public subscription. The public SIDs essentially are overlays of the RF SIDs except for a TF to TF turn instead of the RF legs.

[FlightPathOBN]

9.G,

RNAV RNP, not RNP AR....

Currently the criteria only addresses vertical on approach, it does not address vertical for departure, nor any RF turns.

8168 is TF to TF design, (which is why the containments are so odd looking, accounting for flying inside and over the waypoint)and lays out a foundation for departures, however brief, much more a a placeholder to allow for private departure designs...

note this from 9905...
"The manual includes design criteria to aid States in the implementation of RNP AR approach procedures in accordance with the PBN Manual, Volume II, Part C, Chapter 6, Implementing RNP AR APCH. Similar criteria for departure procedures will be incorporated when developed."

Kijan,
The procedure must be in your navdatabase, because there are a few required points, such as the radial point, that you cannot enter. Essentially, how the box determines a turn, the beginning TF leg, to tan beginning waypoint of the RF leg, maintain "x" distance away from the radial point to the end waypoint of the RF leg, tangent to the TF leg...

[divinehover]

FBO

Your input has validated my concern (confusion). Here's a non-legal question though. What would the risk to safety be in the case of a RF Leg, RNP 1 capable aircraft which hasn't had a full RNP-AR upgrade flying this procedure? Is this a equipage capability issue or a legal issue? Or both?

DH

[alas8]

About manually flying P-RNAV procedure - it is allowed only with GPS as a sensor. It is assumed that FTE (flight technical error) for manual flying is 0.8 nm, so with GPS precision you don't exceed 1 nm limit. Manual means no flight director, just HSI. With other types of sensors like DME/DME, VOR/DME or IRS, positioning error is more significant therefore at least flight director is required to significantly reduce FTE (source - Eurocontrol).
RF legs is a recommended option of P-RNAV specification (ref. JAA TGL 10) so at my opinion if on-board systems support RF legs, they may be flown as RNP-1 procedure.

[FlightPathOBN]

The discussion is not about P-RNAV, it is about RNP-AR...

The difference, among other things, is coded turns...

There are many recommended functions, virtually none of which have been implemented...

DH,

I look at it this way, one is either authorized or not....sure, one can look at a chart, and fly the procedure, but there are many variables, one just may not be aware of...

Even with coded procedures, the different configurations act differently, and are coded differently...the 424 code for a honeywell box on a 737-800, is not the same 424 code for a Thales box on a A320.

While the procedure waypoint may have an altitude at or above, it is working with the other waypoints, and the way the individual box interprets waypoint...this is why public procedures and the coding is having such a tough time, between the rounding up/down, waypoint and other resolution values, they can all act different...that is why when a procedure is designed, is it desktop simmed, full motion simmed, and flight validated PER the specific ac type...

It is very, very difficult to code a multi-variant RNP procedure....

[aterpster]

The "hub" of an RF leg is the "turn point." In implementation in the U.S. that is called the "arc center point."

The reason most FMS vendors won't permit pilots to manually construct RF legs because the RF leg must be at a tangent to the preceding and suceeding leg, which could be a TF leg or another RF leg.

[reynoldsno1]

ICAO DOC 8168 p 520 specifies RNAV RNP DEP criterion

Not quite. It specifies that the Basic RNP-1 navigation specification (as defined in the PBN Manual) can be used to develop RNAV(GNSS) departure procedures. That navigation specification (plus RNAV 1 & RNAV 2) does not require RF functionality. If RF turns are included, then that has to be addressed in national standards.

I believe both Australia & NZ have developed their own RNP(AR) departure crtieria...

[FlightPathOBN]

Given the performance parameters of departure, currently, RNP-AR departures must be individually designed... there is no public criteria that includes a coded RF turn...

if you look into it, the criteria only addresses a straight out missed...

[9.G]

HK has new RNP 1 SID's that use an RF Leg. Are these to be considered -AR (SAAAR for you Yanks) procedures because of the RF Leg or is it merely an issue of equipage? It's a question, not a discussion about RNAV-AR. The answer, in accordance with the published charts 10-3C, is NO it's not RNAV-AR but a simple RNAV RNP 1 SID as it's depicted on the chart. "RF LEG IS REQUIRED ONLY AVAIL TO AC ... FOR RNP 1 OPERATION". Nothing to do with RNAV AR to my understanding. Title determines the requirements.
One of the major differences between RNAV AR and RNP is more stringent accuracy requirement of 0,1 instead of 0,3 apart from others.
@ aterpster, no idea bout the public domain but it's on my IPAD. :ok:

[FlightPathOBN]

One of the major differences between RNAV AR and RNP is more stringent accuracy requirement of 0,1 instead of 0,3 apart from others.

That is not correct.

RNP AR has RF legs, RNP APCH has TF/TF with turns, RNAV straight legs with turns.

RNAV AR...hmmmmm.

Unfortunately, there is much of the information in the text regarding this procedure, that does not show up on the plate...

A19-11 Sup (http://www.hkatc.gov.hk/HK_AIP/supp/A19-11.pdf)

"2.5 RNP 1.0 navigation accuracy is required. Aircraft must be approved by State of Registry in accordance with ICAO RNP 1 standard."
2.6 For those capable and approved aircraft planning to fly the RF SID procedure, voice request for the RF SID via radio frequency from aircrew is required before sending the Pre-Departure Clearance (PDC) request to ATC via data link.
Recommended R/T phraseology from aircrew: ‘Request Radius-to-Fix SID’."

The terminology, as well a the coding are all mixed up on this one....it would be interesting to see how Jepp coded this up...

and from the top of the plate...
http://operationsbasednavigation.com/wordpress/wp-content/uploads/2012/07/SC-111.jpg

Here is what I am not sure how you would be able to meet requirements flying this manually. First off, the procedure has to be in the navdatabase, so then why fly this manually.
Next,how can you maintain on track accuracy and the alert system for the required containment?
Then there is the system RAIM and GPS availability, coupled with on-track error. If this is not coded up, how is all of that engaged....

[aterpster]

FlightPathOBN:

RNP AR has RF legs, RNP APCH has TF/TF with turns, RNAV straight legs with turns.

RNP AR approaches may, or may not, have RF legs. There are many RNP AR IAPs in the U.S. with TF/TF legs and turns. RF legs are an optional application where they present the optimal solution.

The U.S. does not yet have RNAV APCH, but all of our "plain vanilla" RNAV IAPs have TF/TF legs, more often than not with turns.

[FlightPathOBN]

That is correct, they may not, but if there is a coded RF leg, it is AR.

I was also talking about RNP APCH, not RNAV APCH...

While the FAA doesnt call it APCH, in reality that is what these are...

http://flightaware.com/resources/airport/SFO/IAP/RNAV+(GPS)+Z+RWY+10R/png/1

[9.G]

the question relates to departure not the approach. Why is everybody referring to terms for the approach is beyond me. Anyways as for the original question:
I'd recommend to read getting to grips with RNAV AR brochure from Airbus.
With the MOI of 20624/S30934 330/340 aircraft are certified for this departure.
AP OFF with FD on demonstrated accuracy for DEPARTURE is 0,6 NM. NUFF :ok:

[aterpster]

9G:

(t)he question relates to departure not the approach. Why is everybody referring to terms for the approach is beyond me.

Because it is a PPrune thread. :)

[FlightPathOBN]

9.G,

Are you dyslexic or something? The Airbus doc is Getting to grips with RNP AR... NOT RNAV AR...fix it!

BTW, when you are reading that document, the design plates, you are speaking with one of the people responsible for that design. The Departures are a custom criteria, Naverus, Quovadis, and other, have their own custom departure criteria.

While it has been shortened from SAAAR to AR, the meaning is still the same, and just because an aircraft type is certified, doesnt mean your airline bought that package, the aircraft has MAINTAINED cert, or that the Aircrew is certified.

The aircrew must be certified with RNP AR, and maintain cert, just like the ac...including flight validations of the procedures...

Your airline also needs to have operational approval from the authorities, and will likely have RNP values increased until a minimum number of flights have been

The reason the conversation keeps drifting to Approach, is thats all that is available in the public criteria, there is no RNP AR missed, or EO.
ICAO has NOT developed a Departure criteria yet, neither has the FAA....

[9.G]

FPO, chill dude, it was a typo alright? Nobody said the operator doesn't need the approval. Flying this departure implies that operator is approved by it's own CAA, crews are trained and departure is in the DB. You're way too academical for a simple pilot mind. All I need to know is can I fly it or not? I know now my A340 is certified, my airline is approved for RNP OPS. I look into the box and pull up SID called ATENA 1 E, my aircraft is airworthy. DO I CARE bout AR? NO COZ it's not mentioned anywhere on departure plate. OFF WE GO. :ok:

P.S official info published on ATC section for HKG as follows:
RNP-AR APCH PROCEDURES

The RNP-AR APCH procedures are designed to take into account the proximity of high ground and neighbouring airspace. Authorization from Hong Kong Civil Aviation Department is required to fly the RNP-AR APCH procedures. An aircraft operator who intends to conduct the RNP-AR APCH procedures at VHHH shall complete the application form which is available for download at the Hong Kong Civil Aviation Department website: Application Forms (http://www.cad.gov.hk/english/applications.html)

The completed application form and supporting documents shall be forwarded to the Hong Kong Civil Aviation Department as follows at least 30 days prior to the proposed date of adopting the procedures:

Chief, Flight Standards

Flight Standards and Airworthiness Division

Again as you can see not a WORD bout the departure. RNP 1 approval from the CAA of the OPERATOR is sufficient for this departure. BTW many misinterpret the meaning of AR. To my knowledge it means Authorization required from the local authorities of the airdrome location to conduct the APPROACH. Same as for CAT II, III. NO such approval from HKG authorities in this case is required to fly this DEP. Of course provided all other requirements are met.
Note:
Approval usually refers to the CAA of the aircraft registration.
Authorization to the CAA of the airdrome location.

[FlightPathOBN]

You would have to read through the HK A19-11 Supplement to see the requirements.

As I alluded to before this meets the def of an AR procedure, what HK whats from that is what they want, each agency has its own procedures.

[9.G]

FPO, OK here's what I've read and you posted in your quote before:
2.5
RNP 1.0 navigation accuracy is required. Aircraft must be approved by State of Registry in accordance with ICAO RNP 1 standard. Hope that nuff for a engineering mind. :ok:

[9.G]

4 AREA NAVIGATION (RNAV) DEPARTURE PROCEDURES AND RNP BASED DEPARTURE PROCEDURES

4.1 The general principles of RNAV and RNP-based approach procedures apply also to RNAV and RNP-based departures.

4.2 Departures may be based on RNAV VOR/DME, RNAV DME/DME, basic GNSS or RNP criteria. Most FMS-equipped aircraft are capable of following RNAV procedures based on more than one of the above systems. However, in some cases the procedure may specify constraints on the system used.

4.3 To follow a procedure based on RNP, the RNAV system must be approved for the promulgated RNP and it is assumed that all navaids on which the RNP procedure is based are in service (see NOTAMs related to DME stations, GNSS, etc.).

4.4 A route may consist of segments where different RNP values are applicable. Note that the segment with the lowest RNP value is the most demanding one for the flight. Prior to the flight, the pilot must verify that the aircraft is able to meet the RNP requirements specified for each segment. In some cases, this may require the pilot to manually update the aircraft’s navigation system immediately before take-off.

4.5 During the flight, the pilot must check that the system complies with the RNP requirements of the current segment. The pilot must also check in particular the RNP changes along the route.

4.6 The pilot will use the system's information to intervene and keep the flight technical error (FTE) within the tolerances established during the system certification process.

4.7 There are for kinds of turns:

a.
turn at a fly-by waypoint;

b.
turn at a fly-over waypoint;

c.
turn at an altitude/height; and

d.
fixed radius turn (generally associated with procedures based on RNP).

[divinehover]

Let me clear something up here.

My company is a RNP-AR certified operator. The pilots are trained (or will be) for RNP-AR ops. Other aircraft in our fleet have full RNP-AR certification but the A340-300 is not and Airbus doesn't seem too interested in certifying it for RNP-AR ops. The A340-300 can however legally fly RNP 1 SID's and can fly RF Legs.

We will have to get our Nav DB vendor to code these procedures before we use them so there will be no manual insertion into the FMS nonsense.

Can the A340-300 with Honeywell FMS 2 legally fly this procedure if it is in the aircraft's Nav DB?

[aterpster]

divineholder:

We will have to get our Nav DB vendor to code these procedures before we use them so there will be no manual insertion into the FMS nonsense.

Good idea. I doubt you can manually build an RF leg in the 340. I don't know that with certainty however.

Can the A340-300 with Honeywell FMS 2 legally fly this procedure if it is in the aircraft's Nav DB?

Depends your flight ops and the state that holds your certificate. You most likely could not (yet) if you were a U.S. carrier. Once the FAA gets off the dime about non-AR RF legs, and they will, then you would NOT have to be RNP AR qualified to fly those VHHH departures.

[aterpster]

Check out this RF leg:

http://i201.photobucket.com/albums/aa214/aterpster/06053ILDZ11.jpg

[FlightPathOBN]

The HK departure simply mentions "aircraft with appropriate approval' in the text...

My answer with regards to HK is I do not know what they accept. The ICAO criteria is different than the US.
As far as I know, the US does not accept foreign based carriers certification for RNP. We looked at getting Westjet approved for PSP, to no avail. Not sure if ICAO States accept FAA RNP, or who does/does not...

I would suppose you either know you can do this, or you dont...then the next line of defense would be asking to use the procedure..it looks better than the ATENA 2A in the book...which has the beginning waypoints of the turn as fly-over, not fly-by...

then there is the 5000 foot at 5nm PORPA/ROVER

It would be interesting for someone with the procedure in their box, to provide what that data....

terpster...just saw your post...yes, the FAA has been doing this lately, did similar for KSEA approaches from the North...In the profile, it says procedure turn NA?? and of course 20miles out and 195...wahoo

[aterpster]

FlightPathOPN:

terpster...just saw your post...yes, the FAA has been doing this lately, did similar for KSEA approaches from the North...In the profile, it says procedure turn NA?? and of course 20miles out and 195...wahoo

You've lost me. All I see at Seattle for RNAV are ordinary RNAV IAPs without course reversals. Those are all over the country.

[FlightPathOBN]

OK,
thanks for the information...not sure about the RF turns, going from RNAV to VNAV transition...

Yes, it does something, unfortunately, every ones box does something, and not the same. @ of the boxes route GPS data through the IRU, which depending on the manuf and version, can have a pseudo RAIM calc to transition between loss of enough sats, to latency between RNP values in the legs, hence, the varied results and expectations.

"Somewhat complicated" is certainly redundant when dealing with the FAA :mad:
(I gave up after PSP, BDL, and SCC with RNP procedure designs in the US)


terpster,

as OK stated, it looks like KSEA is still provisional, I know Alaska was trying it out some time ago. It a right turn over Elliot Bay (there are no left turns with the FAA :eek:)

[9.G]

Can the A340-300 with Honeywell FMS 2 legally fly this procedure if it is in the aircraft's Nav DB? The requirements are clearly stated on the plate. Are you RNP 1 approved - YES. Do you have this particular SID in the box- YES. Is your aircraft airworthy-YES. So you're good to GO. Decision making in aviation isn't based on ballot principle but on hard core data. It's HKG, not FAA or ICAO or CASA. If not sure just don't do it. :ok:

[FlightPathOBN]

Decision making in aviation isn't based on ballot principle but on hard core data.

You obviously don't know anything about ICAO or the FAA....

The information provided on the HK "plate" was so ambiguous, that experienced designers question the design and the 'aircraft' requirements....

Aside from that, the coding is simply not correct. While the coding from your navdatabase provider may be, if it works, it wont be like what is shown on that supplement....

Good luck!

[9.G]

FPO, get over it dude. You're barking at the wrong tree here. I might be a simple minded bus driver but you remind me on certain characters who love to twist pilot's mind with all this academical crap but when it comes to the decision making they usually scream, sorry Sir but you're the captain. :ok:

[FlightPathOBN]

far be it that the driver, should dismiss any concepts of how the road was designed..

sorry Sir but you're the captain

with your questions and reasoning, I certainly hope that you are not either...

a professional driver understands everything about the road course and his vehicle to optimize the performance...

a hacker drives the vehicle until he crashes...

dont be a hacker...

[aterpster]

FlightPathOBN:

My answer with regards to HK is I do not know what they accept. The ICAO criteria is different than the US.

Which criteria? The design criteria or the approval process? ICAO has accepted FAA Order 8260.52 the ICAO design standard.

As far as I know, the US does not accept foreign based carriers certification for RNP. We looked at getting Westjet approved for PSP, to no avail. Not sure if ICAO States accept FAA RNP, or who does/does not...

If Westjets has been granted operational authority to operate into KPSP, then there is no reason I can think of why the FAA wouldn't authorize the use of the KPSP public RNAP AR approaches. It would seem to be a matter of proper coordination between Transport Canada (or whoever holds Westjet's operating certificate) and FAA's AFS-470 in Washington.

AFS-470 would need to be satisifed that Westjets would, or is, in compliance with the requirements of AC90-101A. Unlike my business aviation friends, who have to jump through the validation hoops for every RNP AR approach, air carriers are required to validate only the RNP AR approaches for their authorized airports.

[FlightPathOBN]

ICAO uses 9905 which is virtually the same for the approach design, but different in that it has a level section (SOC) for the missed approach surface, 8260.52 does not...
http://operationsbasednavigation.com/wordpress/wp-content/uploads/2012/07/SC-12.jpg

8260.52A is supposed to be ICAO compliant, but I havent seen this floating around for years.

Some agencies such as NavCanada, CASA, and others have allowed the use of 8260.52, with an exemption, mostly keeping the RNP at the same level as approach, not jumping to RNP 1 for the missed. (which frequently catches the tower, and drives the DA even higher)

We were trying to get WestJet certified to use the Alaska Airlines RNP procedure into PSP, which as you know, is a custom RNP criteria... There is a public RNP into PSP, but last I heard, ATC would not clear anyone to use it, but that may have changed.

The reason we were told by the FAA why foreign carriers cannot, is that the US airports are not ICAO certified, and in accordance with the Chicago Convention of 1944, PSP or whichever airport, would have to be ICAO certified....

Seems odd, but that is what we were told...

[aterpster]

FlightPathOBN:

ICAO uses 9905 which is virtually the same for the approach design, but different in that it has a level section (SOC) for the missed approach surface, 8260.52 does not...

It doesn't? What would you call Section 1a then?

http://i201.photobucket.com/albums/aa214/aterpster/826052MAS.jpg



Some agencies such as NavCanada, CASA, and others have allowed the use of 8260.52, with an exemption, mostly keeping the RNP at the same level as approach, not jumping to RNP 1 for the missed. (which frequently catches the tower, and drives the DA even higher)

8260.52 provides the option to begin the MAS with the same RNP as final to avoid that tower. Those are all those charts annotated "Missed approach requires RNP less than 1.0."

We were trying to get WestJet certified to use the Alaska Airlines RNP procedure into PSP, which as you know, is a custom RNP criteria... There is a public RNP into PSP, but last I heard, ATC would not clear anyone to use it, but that may have changed.

The Alaska special is not 8260.52 compliant, as are many of their State of Alaska specials. AFS-460 has granted them a deviation from criteria based on fleet performance. I doubt AFS-470 would permit that for another operator. So far as the public procedures go, ATC sometimes balk when the weather is good, but not when one of those winter rain storms makes the 13R RNP AR the only game in town.

The reason we were told by the FAA why foreign carriers cannot, is that the US airports are not ICAO certified, and in accordance with the Chicago Convention of 1944, PSP or whichever airport, would have to be ICAO certified....

Seems odd, but that is what we were told...

Sounds like a old wives tail. :)

[FlightPathOBN]

When I was originally speaking about the criteria of FAA vs ICAO, I was referencing the criteria to become RNP and RNP AR certified, not design ctiteria...

Section 1a is the 50' momentary descent...

The 9905 section is not all that clear, in the 9905 approach, Vpa is the glide path..the section shows obstacles in approach and missed approach...

in the diagram, for the approach obstacle, the OCH line would be extended across to SOC', that is your MOC or level section....an MDA if you will, then it is up to the operator to determine the approach minima, using their own calc for momentary descent, but not crossing the MOC...

Here is how you calculate the origin of the missed approach surface, much different that 8260.52... (Ha is the pressure altimeter height loss for the aircraft category!)

http://operationsbasednavigation.com/wordpress/wp-content/uploads/2012/07/SC-13.jpg

[9.G]

FPO, Aside from that, the coding is simply not correct. While the coding from your navdatabase provider may be, if it works, it wont be like what is shown on that supplement.... FYI, if the DEP is in the DB that means it's been approved by the operator and crosschecked by the relevant departments and is in accordance with the published procedures. BTW this DEP is published in Jeppesen. That doesn't preclude PIC from checking it again. however if it's in the box it's been validated and it's a simple equation for all the aforesaid reasons, namely GO. Now you're a engineer at large, you say. Tell me the difference between a DME ARC and RF from the geometrical point of view? We've been flying DME ARCs outta box for ages and the only difference now is the operation contingency procedure for loss of RNP capability.

On this accord DH asked you a clear cut question Can the A340-300 with Honeywell FMS 2 legally fly this procedure if it is in the aircraft's Nav DB? I haven't seen your clear cut answer yet.

[aterpster]

FlightPathOBN:

When I was originally speaking about the criteria of FAA vs ICAO, I was referencing the criteria to become RNP and RNP AR certified, not design ctiteria...

Section 1a is the 50' momentary descent...

The 9905 section is not all that clear, in the 9905 approach, Vpa is the glide path..the section shows obstacles in approach and missed approach...

in the diagram, for the approach obstacle, the OCH line would be extended across to SOC', that is your MOC or level section....an MDA if you will, then it is up to the operator to determine the approach minima, using their own calc for momentary descent, but not crossing the MOC...

Here is how you calculate the origin of the missed approach surface, much different that 8260.52... (Ha is the pressure altimeter height loss for the aircraft category!)

And, none of that would have anything to do with Westjets getting FAA approval to use the public KPSP RNP AR instrument approach procedures.

[FlightPathOBN]

terpster,

2 different question with relative answers.

9.G,

When you fly a DME arc, you are staying a certain distance away from the DME correct? So the DME is a radial point per se.
With an RF turn, your flying a certain distance away from a radial point. That radial point is a coded waypoint in the navdatabase.
There is quite a bit of difference flying a 25nm DME arc, than a 3nm RF turn and staying on course.

As far as answering DH question, I believe it already has been answered. The regulations are minimum requirements, Equipage and training have minimums as well.

You are misreading what Boeing and Airbus say about the aircraft, these aircraft meet the minimum requirements to be certified.


From Airbus:
The process to obtain an operational approval will be initiated by an application sent by the airline to its national authorities.

The airline with its national authorities will need to determine the aircraft equipment and the level of aircraft certification adequate for the intended type of RNP AR operations. The level of operational requirements and the way the national authorities will supervise how the airline comply, may influence this decision.

The list of required equipment should be established during the operational evaluation and the approval process, considering the available operational mitigation means for each individual procedure.

The following list of equipment should be considered to start an RNP AR procedure in a demanding environment:
- 2 FMGC (2 FM required for RNAV approach)
- 2 MCDU
- 2 FD
- 1 AP, but 2 AP if RNP < 0.3 for approach, or RNP < 1.0 in go around or departure, is required
- EFIS DU with 2 L/DEV and 2 V/DEV displays and RNP P/B (if installed)
- 2 GPS (MMR) (2 GPS required for RNAV approach)
- 3 ADIRS (2 ADIRS for a departure)
- EGPWS
- FCU with both channels

Extract of AC 90-101(Appendix 6, 12/15/2005)
1. The operator must have an RNP monitoring program to ensure continued compliance with the guidance of this AC and to identify any negative trends in performance. At a minimum, this program must address the following information. During the interim approval, the operator must submit the following information every 30 days to the CHDO or FSDO granting their
authorization. There-after, the operator must continue to collect and periodically review this data to identify potential safety concerns, and maintain summaries of this data.
a. Total number of RNP AR procedures conducted.
b. Number of satisfactory approaches by aircraft/system (Satisfactory if completed as planned without any navigation or guidance system anomalies).
c. Reasons for unsatisfactory approaches, such as:
1) UNABLE REQ NAV PERF, NAV ACCUR DOWNGRAD, or other RNP messages
during approaches.
2) Excessive lateral or vertical deviation.
3) TAWS warning.
4) Autopilot system disconnects.
5) Nav data errors.
6) Pilot report of any anomaly.
d. Crew comments.


The application should describe the project and the strategy chosen by the airline to comply with the applicable regulation.
The project may have quite different implications depending the level of RNP AR that is envisaged or if the project is to fly an existing public procedure or to develop a private (or tailored) procedure.

The ACD referenced in the AFM should be used to support the airline’s operational approval.
When the intended RNP value is lower then the Airbus demonstrated values in abnormal conditions, the airline must perform a Flight Operations Safety Analysis (FOSA) for the specific procedures being envisaged. When the RNP values in abnormal conditions are used no FOSA is required.
The operational evaluation will need to be reviewed by the national authorities, as it may induce specific operational requirements.
The overall check of the aircraft capability to fly the intended procedure, but also that the flight crew procedures and training are adequate, will be made during one (or more) validation flight(s) in good weather conditions (VMC).
The authorities may require the airline to accumulate a minimum experience during revenue flights with higher weather minima before granting approval to the lowest minima

Here is the Airbus deliverable to the airline to help with RNP authorization:

• The Airworthiness Compliance Document (ACD) and FM revision,
• Updated FCOM for aircraft with RNP AR certification (FM+ACD)
• Flight Crew Training
o Ground CBT course,
o Simulator training and simulator check for RNP AR (generic),
• Flight Operations Monitoring with AirFASE

The cert isnt for just the aircraft, it is for the airline, aircraft, and crew per the airlines State.

[9.G]

alright FPO, here's your next question can you fly a DME ARC with U/S NAV AID? As for the answer I'd like to see one word: YES or NO? :ok:

[FlightPathOBN]

Were you able to read, and well comprehend the post? http://www.pprune.org/7298826-post59.html which detailed the regulations?

I see that you are testing the old adage,

You have proven there are no stoopid questions, just stoopid people...

As I stated before, I hope that you are NOT a Captain anywhere...
("capt of a 150 doesnt really count..)

Again,

Good Luck!

[aterpster]

FlightPathOBN:

The cert isnt for just the aircraft, it is for the airline, aircraft, and crew per the airlines State.

That's what I have been trying to state with respect to Westjet and RNP AR at KPSP.

1. Transport Canada

2. FAA AFS-470

3. Full compliance with AC-90-101A

[FlightPathOBN]

I understand, but that is what were were told by the FAA, it must have been just for the custom RNP AR...

https://docs.google.com/viewer?url=http%3A%2F%2Fwww.easa.europa.eu%2Fevents%2Fdocs%2 F2010%2F20-10_2%2F06%20RNP(AR)%20WS%20USA%20Lessons%20Learned%20KTPB.pd f&docid=ffe209102f5c94b79a860f4222063422&a=bi&pagenumber=9&w=749

[9.G]

OK FPO, regardless of you fallouts the topic needs clarifications. First of all, airbus allows to fly DME ARC with unserviceable NAV AID, which essentially is nothing but a radius to reference point. VOR DME is stored as a reference point in our data base that's why we need to check NAV accuracy in TMA and if not satisfactory revert to raw data. No such option is available for RNP and that's the only difference. As stated before contingency is what's relevant for this type of approach. From technical and geometrical point of view however there's no difference at all. The question is however related to SID. I recommend you to read 17th airbus safety conference brochure S RNP-AR publication in which there's a table classifying what's AR and what's not. DEP and/or missed approach RNP < 1 NM is AR. 1 NM is NOT AR. You gotta give the befit of the doubt and maybe some credit to others. :ok:

[FlightPathOBN]

please provide a link to the reference document you are talking about.

From doc 9905 RNP procedure design manual

2.1.1 RNP APCH versus RNP AR APCH
2.1.1.1 RNP APCH is defined as an RNP approach procedure that requires a lateral TSE of +/-1 NM in the initial, intermediate and missed approach segments and a lateral TSE of +/- 0.3 NM in thefinal approach segment. Guidance on implementing RNP APCH operations can be found in the PBN
Manual, Volume II, Chapter 5, Implementing RNP APCH.
2.1.1.2 RNP AR APCH is defined as an RNP approach procedure that requires a lateral TSE as low as +/- 0.1 NM on any segment of the approach procedure. RNP AR APCH procedures also require that a specific vertical accuracy be maintained as detailed in the PBN Manual, Volume II, Chapter 6.

http://operationsbasednavigation.com/wordpress/wp-content/uploads/2012/07/SC-14.jpg

[aterpster]

9.G:

No such option is available for RNP and that's the only difference.

For the avionics engineer the coding is different for an RF leg than a DME ARC.

This is significant to the crew in the respect that the crew has no idea where the center point of an RF leg is, unlike a DME ARC.

Another significant difference between RNP AR and all other forms of RNAV procedures is that, in accordance with the table FPO posted, an RNP AR IAP does not have to taper down as it progresses towards the runway. Segment widths can decrease, then increase, then decrease, except no segment can be of a lesser RNP value than the final segment, and the final segment cannot vary in width in a given IAP. Also, there is no secondary area obstacle protection, unlike all other instrument procedures.

[FlightPathOBN]

sounds good terpster,

I would also add that currently, the public RNP design criteria does not address DEP. It will be included in 8260.PBN, whenever that may happen...RNP 1 DP Specials (http://www.faa.gov/about/office_org/headquarters_offices/avs/offices/afs/afs400/afs420/policies_guidance/memo_TILS/media/RNP-1_DP.pdf)


other RNP 1 reference....
RNP 1 AC90-105 (http://www2.icao.int/en/pbn/ICAO%20Documentation/State%20and%20International%20Organization%20Publications/AC%2090-105-RNP%20and%20Baro-VNAV.pdf)

(1) Pilots must not fly an RNP 1 procedure unless it is retrievable by the procedure name from the onboard navigation database and conforms to the charted procedure. Numeric values for courses and tracks should be automatically loaded from the RNP navigation database for required leg types. However, the procedure may subsequently be modified through the insertion or deletion of specific waypoints in response to ATC clearances. The manual entry or creation of new waypoints, by manual entry of latitude and longitude or rho/theta values is not permitted.
Additionally, pilots must not change any database waypoint type from a fly-by to a fly-over or vice versa.
(2) The pilot must confirm the correct procedure is selected. This process includes confirmation of the waypoint sequence, reasonableness of track angles and distances, and any other parameters that can be altered by the pilot, such as altitude or speed constraints. A navigation system textual display or navigation map display must be used.
(3) For RNP 1 procedures, pilots must use a lateral deviation indicator, flight director, or autopilot in lateral navigation (LNAV) mode. Pilots of aircraft with a lateral deviation display must ensure lateral deviation scaling is suitable for the navigation accuracy associated with the procedure.

Functional Requirements.
(1) Autopilot and Flight Director. RNP procedures with RF legs require the use of an autopilot or flight director with at least “roll-steering” capability that is driven by the RNP system. The autopilot/flight director must operate with suitable accuracy to track the lateral and, as appropriate vertical paths required by a specific RNP procedure.
(2) The aircraft must have an electronic map display depicting the RNP computed path of the selected procedure.
(3) The flight management computer, the flight director system, and the autopilot must be capable of commanding a bank angle up to 25 degrees above 400 feet AGL.
(4) Maintaining LNAV in missed approach. If abandoning a procedure while on an RF Leg or initiating a go-around or missed approach (through activation of TOGA or other means), the flight guidance mode should remain in LNAV to enable display of deviation and display of positive course guidance during an RF leg. If the aircraft does not provide this capability, crew procedures must be used that assure the aircraft will adhere to the specified flight path during the RF Leg segment.
NOTE: For missed approaches with a RF Leg, the flightcrew must be able to couple the autopilot or flight director to the RNP system (engage LNAV) by 500 feet AGL.

[FlightPathOBN]

The flavor of the regs makes the assumption that the procedure may have been changed in the aircraft database by another pilot.

There are 2 main reasons why there all of the verbiage on verification of what is on the plate, concurs with what is in the FMC.
Verification that what shows up in the FMC is what is shown on the plate, and;
for you to make verify that your aircraft has the ability to perform the procedure.

In the case of the HK departure, the procedure mandates 5000 feet at 5nm from runway end, basically 1000 feet/nm climb rate. If your aircraft cannot make that, YOU must assume the procedure is NA.
It is up to the pilot, even if the procedure is in the FMC to select, if with conditions, the ac cannot comply.

Throughout my numerous posts on this site, I have been extremely vocal about adding any waypoint data, this is why.
One may accidentally overwrite a waypoint used in another procedure without even knowing it.
When you or another operator enters the other procedure, you may or may not realize the error, especially waypoints that are not part of a distinct RNP procedure.
Once the navdatabase has been uploaded on to the ac, there is NO error checking other than the AIRAC cycle.

[9.G]

FPO, I tried copying it but for it doesn't work here but if someone can copy paste that table I'd appreciate it.

This is significant to the crew in the respect that the crew has no idea where the center point of an RF leg is, unlike a DME ARC. and how am I supposed to know that with DME being U/S? That's the whole point here. It might be depicted on the chart but if it's U/S there's no way to confirm it with raw data but as long as GPS is primary, accuracy based on a/c FMS calculation algorithm, is sufficient. DME ARC as RF is flown outta DB. The coding might be different but from operational point of view there's no difference whether I'm flying a RF leg or DME ARC without DME indication.

Another significant difference between RNP AR and all other forms of RNAV procedures is that, in accordance with the table FPO posted, an RNP AR IAP does not have to taper down as it progresses towards the runway. Segment widths can decrease, then increase, then decrease, except no segment can be of a lesser RNP value than the final segment, and the final segment cannot vary in width in a given IAP. Also, there is no secondary area obstacle protection, unlike all other instrument procedures. That's all covered by the operational approval. I don't need to immerse into technicalities as I like to KISS. Keep it simple and short. Approval is enough grounds to make a decision.:ok:

[jorgesvrider]

If the aircraft is rnav1 sids stars aproved and is capable of rf legs you can fly all the procedures rnav 1 except those listed as "ar"authorization requiered but that only means that the crew requires special training for that specific chart, and when the airline give that training is just for that specific procedure not for all the "ar"procedures.
Just like the aproaches if you are rnp0.3 you can fly
all the rnp aproaches ( rnav gps "gnss" ) but you cannot fly
the rnp ar aproaches ( rnav rnp ) unless you get the special
trainning and aproval .

[9.G]

s Rnp Rnp Ar Approaches (http://www.scribd.com/doc/100667759/s-Rnp-Rnp-Ar-Approaches) it's on the page 9. :ok:

[FlightPathOBN]

http://operationsbasednavigation.com/wordpress/wp-content/uploads/2012/07/SC-16-e1342881588842.jpg

You are taking this table out of context.
For this presentation they are referencing Approach and Missed Approach.

The lack of a check, does not mean it is not considered AR at RNP 1.

Rather than a powerpoint, I would suggest the criteria, and design criteria.

[9.G]

FPO, how bout this one then
SECTION 2. AREA NAVIGATION (RNAV) AND REQUIRED NAVIGATION PERFORMANCE (RNP)
1. RNP Levels. An RNP “level” or “type” is applicable to a selected airspace, route, or procedure. As defined in the Pilot/Controller Glossary, the RNP Level or Type is a value typically expressed as a distance in nautical miles from the intended centerline of a procedure, route, or path. RNP applications also account for potential errors at some multiple of RNP level (e.g., twice the RNP level).
(a) Standard RNP Levels. U.S. standard values supporting typical RNP airspace are as specified in TBL 1-2-1 below. Other RNP levels as identified by ICAO, other states and the FAA may also be used.
TABLE 1-2-1 U.S. Standard RNP Levels

RNP Level
Typical Application
Primary Route Width (NM) - Centerline to Boundary
0.1 to 1.0
RNP SAAAR Approach Segments
0.1 to 1.0
0.3 to 1.0
RNP Approach Segments
0.3 to 1.0
1
Terminal and En Route
1.0
2
En Route
2.0
NOTE:
1. The“performance”ofnavigationinRNPrefersnotonlytothelevelofac curacyofaparticularsensororaircraftnavigation system, but also to the degree of precision with which the aircraft will be flown.
2. Specific required flight procedures may vary for different RNP levels.

(b) Application of Standard RNP Levels. U.S. standard levels of RNP typically used for various routes and procedures supporting RNAV operations may be based on use of a specific nav- igational system or sensor such as GPS, or on multi-sensor RNAV systems having suitable performance.
(c) Depiction of Standard RNP Levels. The applicable RNP level will be depicted on affected charts and procedures. You can find it in Jeppeen Radio data general p 225. It's official source. You're one stubborn son of gun.:ok:

[FlightPathOBN]

The procedures that you see in that presentation, I have designed, provided the obstacle and flight validation, as well as trained the crew in SIM and flight val.

There is always one in the class that just doesnt get it.

[9.G]

Hang on a sec FPO, let me just get it straight here. I can live with the idea of me being a slow grasping pupil. I find it however highly improbable that all the other reputable organisations like Airbus, Jeppesen and last but not least wikipedia Required navigation performance - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Required_navigation_performance) concept description all got it wrong. Come on mate, be reasonable. It's far more simpler than you're trying to picture it. It's black on white: when AUTHORIZATION IS REQUIRED it's clearly depicted on the chart. The comparison RNP approaches include capabilities that require special aircraft and aircrew authorization similar to category II/III ILS operations. is the best way to understand SAAAR or AR. While operator must be approved for LVO no authorization is required for LVO take off unlike approach. That's why HKG ATC section speaks only bout the approach. That's why there's nothing mentioned about AR on the departure plate. It's really been fun. :ok:

[aterpster]

9.G:

I find it however highly improbable that all the other reputable organisations like Airbus, Jeppesen and last but not least wikipedia Required navigation performance - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Required_navigation_performance) concept description all got it wrong.

Wikipedia did get one item wrong, or at least incomplete, and I quote:

When conducting an RNP SAAAR approach with a missed approach less than RNP 1.0, no single-point-of-failure can cause the loss of guidance compliant with the RNP value associated with a missed approach procedure. Typically, the aircraft must have at least dual GNSS sensors, dual flight management systems, dual air data systems, dual autopilots, and a single inertial reference unit.

At least one IRU is also required when any part of the approach phase requires RNP of less than 0.30, even though the missed approach may not require RNP of less than 1.0.

From a pilot perspective RNP AR is easy, as are operational concepts and actual flying of the procedures.

What is not easy are the hoops the airframe OEM has to jump through to qualify the aircraft, what the operator of an RNP AR aircraft has to do to validate the database and its performance in any qualified airframe's FMSes, and the design and flight inspection requirements.

There are so many different FMSes out there with so many variables in software, it is mandatory that the additional database and performance validation steps must be taken to assure performance on the often far less forgiving RNP AR approach procedures.

[9.G]

I gotcha aterpster and no objections there. Nobody said obtaining the approval will be a walk in the park. However that's not the point here. Again that's what's it all bout : My company is a RNP-AR certified operator. The pilots are trained (or will be) for RNP-AR ops. Other aircraft in our fleet have full RNP-AR certification but the A340-300 is not and Airbus doesn't seem too interested in certifying it for RNP-AR ops. The A340-300 can however legally fly RNP 1 SID's and can fly RF Legs.

We will have to get our Nav DB vendor to code these procedures before we use them so there will be no manual insertion into the FMS nonsense.

Can the A340-300 with Honeywell FMS 2 legally fly this procedure if it is in the aircraft's Nav DB?

It's a plain language question with all the prerequisites given. Let's see:
HKG published new SIDs with RNP1 and RF for noise mitigation purposes. The requirements for those SIDs are published and clearly written on the plate and AIP. The operator is approved for RNP 1 as per OPS SPECS. SID is in the DB as published. BTW no approval will be granted by the state of a/c registry unless vendor's DB has been demonstrated to be satisfactory. OpSpec/MSpec/LOA C063, Area Navigation (RNAV) and Required Navigation Performance (RNP) Terminal Operations is an example of OPS SPECS approval. Provided the aircraft is airworthy there's absolutely nothing precluding DH from flying this SID. All this fuss about SAAAR or AR APPROACHES is completely irrelevant to this issue. DH isn't interested in academical particularities of design criteria. He's an operator like me and sitting in the cockpit before departure my only concern is CAN or CAN'T I fly it? Again no need to mastrubate his brain.
I'm done here. :ok:

[BOAC]

Again no need to masturbate his brain. - classic and correct. This is an example of how our 'experts' can take a reasonably straightforward question, run it to 76 posts and still not provide a proper answer.:ugh:

[aterpster]

BOAC:

- classic and correct. This is an example of how our 'experts' can take a reasonably straightforward question, run it to 76 posts and still not provide a proper answer.:ugh:

Only the certificate holder and the government holding that certificate can provide the "proper answer" to the question posed.

In any case, threads like this do expand by follow-on questions and comments posed.

Isn't that what an Internet forum is about?

[BOAC]

DH and 9.G - I'm sure you know this link, but I dug it out from Google in case it casts any light on the topic.

http://www.ecacnav.com/downloads/4.2%20T%20Fixy%20Airbus.pdf

[divinehover]

Thanks for the laughs guys.

We are in discussion with the HK Authorities and I'll provide the formal answer soon.

DH

[FlightPathOBN]

DH,
Well good luck! At least you no know more about RNP procedure design than you ever hoped for Keep us informed on what happens, of course now we all want to know!

He's an operator like me and sitting in the cockpit before departure my only concern is CAN or CAN'T I fly it?

If you had approval, you wouldnt be sitting there wondering, you would already know.

As far as the A340-300, sure it can be RNP capable. If that particular airline ordered enough equipage, or if the certs have been maintained, there is no way for any of us to guess....

In the US, it has been difficult for the airlines. Many of them spent quite a bit of money getting equipped, certified, and trained, only to find out they seldom get to use RNP. Just as with alot of the CATIII ILS, the airlines are letting the calibration, certs, and recency expire, to save money on costs.

[aterpster]

FlightPath:

In the US, it has been difficult for the airlines. Many of them spent quite a bit of money getting equipped, certified, and trained, only to find out they seldom get to use RNP. Just as with alot of the CATIII ILS, the airlines are letting the calibration, certs, and recency expire, to save money on costs.

Because they ended up placing too many RNP AR approaches were they are not needed nor particularly useful. Their purpose is where a significant terrain issue can only be resolved with RNP AR and, in a very few cases deconfliction and noise abatement.

If the FAA would get off the dime about letting non-astronauts fly RF legs, than ordinary RNAV IAPs with RF legs would provide the commonality ATC needs at very busy airports.

RNP AR has been terribily over "installed" in the U.S. and that continues because of programs and goals to be met by desk pilots.

[FlightPathOBN]

terspter,

Completely agree...
the FAA went for quantity, not quality.

The concept and reliance on idle descent as a selling tool, alleged fuel and track mile savings was a big mistake, when the airline figured out it didnt save any fuel, and RNP vs non-RNP traffic was not easily blended with current ATC toolset.

SW spent quite a bit of money upgrading their fleet, training, and the OpSpec took about 3 years to get...all that a no place to go.

All that is really necessary is to install the standard T" or "Y" configuration, use 4 mile TF legs instead of 5, then transition to 4nm radius RF turns once the pattern is established.

Simple, effective, straightforward for cert and application.

[aterpster]

All that is really necessary is to install the standard T" or "Y" configuration, use 4 mile TF legs instead of 5, then transition to 4nm radius RF turns once the pattern is established.

TF legs that short with a large course change are not permitted by Order 8260.54A. 8260.54A is more conservative in most respects than previous RNAV criteria directives.

RF legs are permitted but they must terminate not less than 2 miles prior to the FAA. But, the FAA has yet to approve avionics (other than for RNP AR) for RF legs.

[FlightPathOBN]

54A?

what is that approved for?

I am an ops guy and design what works, not what any formula based criteria conjures up.

If you mean the FAF, that is also incorrect. There are several methods of termination of RF turns...related to a stabilized approach. One can have a FRP at 15 or 30 seconds before the DA, or by 500 feet FRP.
(FRP =final roll point)

[aterpster]

FlightPathOBN:

54A?

what is that approved for?

I am an ops guy and design what works, not what any formula based criteria conjures up.

It is approved and required for U.S. RNAV IAPs other than RNP AR.

I am sorry, I thought you were a procedures designer.

No wonder you have issues with FAA approvals since you view their current non-RNP-AR criteria order with apparent contempt.

[divinehover]

Ok, here's the answer

The HK authorities just need to see a copy of our Company Ops Spec which says our local authority approves the company to operate RNP 1 SID's with an RF Leg. We obviously don't have this yet because there have never been such a Nav Spec requirement in the past. I have shown our authority that aircraft are capable of such a procedure and they are happy. Just a paper work exercise really.

The new 4th Edition of the ICAO PBN Manual (doc 9613) also deals with this issue. Expect more of these types of procedure in the future, they make a lot of sense in busy airspace.

DH

[aterpster]

divinehover:


The new 4th Edition of the ICAO PBN Manual (doc 9613) also deals with this issue. Expect more of these types of procedure in the future, they make a lot of sense in busy airspace.

The FAA is presently in coordination with the first STAR with an RF leg. The process is not going smoothly, however. Not the least of all, the TRACON is having hissy fits about it:

http://i201.photobucket.com/albums/aa214/aterpster/SYMONONE.jpg

[OK465]

Why does the chart show SADDE at a mandatory 250K, but the route description says cross SADDE at 210K?

(edit: the 210 would appear to be the error since SMO requires a mandatory 230K)

[FlightPathOBN]

How did you come to that conclusion?

There are hundreds of procedures with speed restrictions on waypoints.

I have several approach procedures with a waypoint at FL10, with a speed restriction of 250kts, a waypoint at 5000 with a restriction of 210, and a waypoint at 3000 with a speed restriction of 180kts.
(note the 'at' for altitude, not 'at or above')

If you set a speed restriction on a waypoint, it will be 'at', crossing that waypoint, not 'at or below'...

There are several procedures with the A320, with a Thales box, where you have to set the waypoints to 'at', or the ac will porpoise down to the next 'at or above' waypoint.

If no speed restrictions are placed on a waypoint, the speeds will default to the alt/speed settings in the box such as 250kts, at or below 10,000 ft.

[FlightPathOBN]

OK,

I see what you are saying, and yes, depending on the ac, and software version, there can be these issues, but these issues can be very variant/box specific, not simply Boeing or Airbus.

There is some coding tricks that I have used to get around some of these issues, but many times you just cant fight the depth of the box...

it was quite the surprise to see that the Smiths box on the NG would not accept an airport elevation over 10,000 feet, and how difficult it was to finally get that to work...

the further we get into these boxes, the more difficult it seems to become, and these issues certainly makes automating CDA, idle descent, TOD, and trajectory management difficult, if not near impossible to achieve...

(and they wonder why a public RNP procedure is so difficult to design)

[aterpster]

FlightPathOBN:


the further we get into these boxes, the more difficult it seems to become, and these issues certainly makes automating CDA, idle descent, TOD, and trajectory management difficult, if not near impossible to achieve...

(and they wonder why a public RNP procedure is so difficult to design)

Those sound like issues with design of special RNP AR IAPs for a particular operator.

The only deference the FAA has made to avionics in the design of public RNP AR IAPs (and we have a whole lot of them now) is not less than 50 seconds of flight between the FROP and the DA to accommodate the AB, and that is only if the missed approach is an RNP missed approach (less than RNP 1.0). Otherwise it is not less than 15 seconds. This is to accommodate transition to GA mode. The only other accommodation, and it is very broad, is that an IRU is not required for RNP AR IAPs of not less than 0.30, and without missed approaches of less than RNP 1.0.

It's up to the airframe OEMs to address the multitude of specific avionics issues in order to obtain RNP approach level approval.

Difficult to obtain that approval and for the operator to validate the RNP AR database? Yes.

Difficult to design public RNP AR IAPs? No, at least not in the United States. The only major impediment to public design is ATC and impossible terrain at a very few locations.

[FlightPathOBN]

Procedures are not difficult to design, but procedures that actually work are.

That is why there are such the issues with ATC, RNP with multi-variants was never envisioned in the criteria, as it is built around a 737NG with a Smiths box.

As noted by OK, the boxes act differently, so will the procedures. If you try to put an A320 with a Thales box, on the same procedure that was for a 737NG with a SMiths box, it may not, and most times, does not work. That is why one cannot use the criteria, or the spreadsheets with anything but limited success..hell, they have few turns because TARGETS cant design a turn correctly, the wrong great circle algorithm was used, at least they can use SAAR-Pro, or RNAV-Pro, then dump the results into TARGETS for the database.

Then you assume that you are the only ac in the sky, how do multiple ac of different types, use the procedure, and provide ATC the ability to control the ac?

When you design an multi-variant RNP approach procedure, with a queue ranging from 737, 320, E90, 744, and A380, with Smith, HW, and Thales FMC, and keep them at radar or wake sep, with ATC guidance...
then you will understand what difficult is.

[aterpster]

That's why we have the database verification and flyability requirements set forth in AC90-101A.

If the procedure doesn't pass muster with a particular airframe/FMS combination, it cannot be loaded in that airframe/FMS combination, at least not in the U.S.

[FlightPathOBN]

Meeting the criteria and flyability have only so much to do with ATC operations.

While the ac may perform just fine, the procedure in itself is worthless if ATC cannot manage it.

As an example, the 737-800 in the US is a CAT C ac, with FAS of 140kts. According to the criteria, the entire final approach segment must be flown at a max speed of 140 kts. If there is a turn to final, the max speed of that turn is 140 kts.

With a 5 to 7 mile final approach segment, how often do you see a 737 anything, at 140 kts 5 nm out? Add a turn, and you have the 737 or CAT C ac at 140 kts for 10 nm out.

Allegedly, these aircraft are all on idle descent, so the 320, 734, 738, 744, and others, are all happily gliding down on a 3 degree glidepath, and ATC is supposed to keep them all properly separated, and somehow try to optimize the spacings and queue?

The reality is that if the criteria pumps out procedures that ATC, with current tool sets, cannot manage, then the procedures are rubbish...

[aterpster]

FlightPathOBN:

Two different issues. I agreed with you on the ATC aspects several messages ago. RNP AR was intended to solve difficult terrain issues and typically at airports where ATC couldn't care less such as Rifle, Colorado and Bishop, California.

But, along comes an airline with more money than insight and thinks they will save a few gallons of Jet A every leg with RNP AR at high traffic locations.

Now that it is obvious even to them that it isn't working they are whinning to the highest levels of the FAA. That, of course, will get them nowhere.

I believe that very limited use of RF legs on SIDs and STARs will eventually prove to be useful, once most of the operators, including business aviation, are approved for non-RNP AR RF legs. But, that is it. Forget RNP AR IAPs at high traffic locations except special cases like down the river at KDCA.