Helicopter Non-Precision Approaches [Archive]

212man

1st Aug 2013, 06:03

A subject dear to my heart! We - or should I say, my operator until yesterday ;) - adopted the CDFA NPA concept when we introduced the S92s. We add 50 ft to the MDA and treat it as a DA (ala FW) though, depending on the location of the MAPt and the VPATH coding, the MAPt may come first. Every approach is thus flown in the same manner with the same sight picture at the bottom - ILS, NDB, VOR, RNAV. Many NPA approaches are now approved - and published - as allowing the MDA to be used as the DA. This reflects the fact that the approach is being flown at approx 3° (5.2%), rather than the assumed 15% gradient used for OCH calculations by ICAO Doc 8168.

The fundamental misunderstanding amongst many pilots who argue against this concept is that somehow the MAPt relates to the ability to land from the approach - it does not. The MAPt is the first point from which the Missed Approach Criteria are defineable, and in no way implies that a safe approach can be made from - or just before - that point. Consider an NDB approach, with the MAPt at the NDB in the mid-field with an MDH of 650 ft - how can you safely conduct an approach and landing from that point? Dump the collective, and practically enter autorotation? Turn downwind and descend - back into IMC possibly?

I could go on, but I have a plane to catch.....:ok:

crowgwu

1st Aug 2013, 06:26

I've ever heard of a similar incident in the last 35 years.

Stallion85

1st Aug 2013, 07:23

I must admit its the first time I hear something about this procedure.
I haven`t flown IFR for quite a while now but when was this procedure introduced? I have never seen an approach like this on the charts I used. (or maybe overlooked it)

Nevertheless, although I don't see anything wrong with the procedure, I can't find the big (or even a small) benefit.

212man, I use your post to explain my point of view.
Correct me if I missed or misunderstood something.

We add 50 ft to the MDA and treat it as a DA (ala FW) though, depending on the location of the MAPt and the VPATH coding, the MAPt may come first. Every approach is thus flown in the same manner with the same sight picture at the bottom - ILS, NDB, VOR, RNAV. Many NPA approaches are now approved - and published - as allowing the MDA to be used as the DA. This reflects the fact that the approach is being flown at approx 3° (5.2%), rather than the assumed 15% gradient used for OCH calculations by ICAO Doc 8168.

As long as I stay above the MDA I can (legally) descend / climb however I want!? The MAPt defines the point I have to start the climb out (at least) and the MAP. (I can start the climb way before the MAPt but have to track to the MAPt to start the MAP in regards of turns etc.)
So why do they have to be approved for this?

The fundamental misunderstanding amongst many pilots who argue against this concept is that somehow the MAPt relates to the ability to land from the approach - it does not.

The MAPt is the first point from which the Missed Approach Criteria are defineable, and in no way implies that a safe approach can be made from - or just before - that point.

Consider an NDB approach, with the MAPt at the NDB in the mid-field with an MDH of 650 ft - how can you safely conduct an approach and landing from that point? Dump the collective, and practically enter autorotation? Turn downwind and descend - back into IMC possibly?

The following applies for day operations:

Consider clouds broken at 650ft. You fly the 3° approach and there is this cloud layer right at the place you reach your "DA". You see nothing
(at 700ft!, cause you added 50ft for the DA. You are allowed to dip under the DA but you are not allowed to plan it. Actually, the approach would be a waste of time, because you already know you won't become visual before you start the approach) and start the MAP (or at least the climb).

The second in sequence is a guy flying the "dive and drive" procedure.
Lets assume the clouds did not move to give both the same situation.
After a quick (no autorotation of course) descent he reaches the MDA far before the MAP. He starts to cruise at 650ft and (because of the BKN cloud layer being at 650ft) he is lucky to find a "hole" in the clouds, descents further below MDA (now visual) and performs a visual approach.

Now lets assume he did not get visual on his way to the MAPt but gets visual at the MAPt. (The NDB is midfield) He descents below the MDA as far as possible (remains the required ground clearance) and performs a circling approach.

Visibility requirements should be considered, too. If you don`t find the requested VIS you start the MAP even if you are outside the clouds.

I understand your point, but we are still in the helicopter section, aren't we?
Circling with a helicopter is... well... not that difficult. You can slow down legally to 60 KIAS (CAT H) or 70 KIAS (CAT A).

Again, in my eyes its legal but not really practical or even safer.

[email protected]

1st Aug 2013, 08:37

The only problem with the CDFA concept is that you end up with situations like the one 212man describes, where the MAPt is at the beacon in a difficult place to make a landing from if you do happen to get the references. Not only do you not get to the minima but converting to a visual approach to land is made more difficult.

What is wrong with flying an approximate 3 degree approach but adjusting the RoD (but complying with any step-fixes) so that you get to MDA a reasonable distance before the MAPt? That way you can fly the approach to the actual minima and have the opportunity of gaining the required visual references in stable level flight (probably using the alt hold) before the MAPt.

It seems a nonsense to apply FW techniques to RW just for the sake of commonality when there is no real benefit - this procedure is all about removing trim changes and the potential for CFIT from FW approaches - really not applicable to RW.

The idea that all approaches then look the same is really dumbing down what pilots get paid for - can't imagine this will be used in the offshore environment where that extra 50' will make the difference between getting to the rig (and keeping everyone happy) or going home or diverting.

The MAPt is where the calculated obstacle clearance planes guarantee terrain clearance if the MAP is followed - one could argue that if you are still descending as you pass the MAPt (even if you have added 50') you will be below the obstacle planes (albeit probably briefly) as you initiate the go-around - this is not the case if you come in level and go-around from that configuration at the MAPt.

212man

1st Aug 2013, 09:07

Crab - CDFA means Constant Descent Final Approach. i.e. it is the nominal 3 degree approach you describe. The problem with an awkward MAPt I was referring to was the traditional 'step down' or 'dive and drive' all the way to the MAPt concept. Why do I want to be in "stable level flight"? I want to be in a stable approach, surely? My discussion was only related to Onshore published procedures and has no relevance to offshore ops.

Stallion, your point about 'descending through a hole' is understandable, but dooes not meet the 'Required Visual References' criteria and should you subsequently be faced with going IMC again will leave you poorly placed. Similarly, your circling suggestion could be bad news - why weren't you visual before the MAPT? Maybe because the cloud was thicker and lower before that point, and now you are turning and descending towards it! With broken cloud, there is always the possibility of encountering that unwanted 'okta' at the DA, regardless of the type of approach - PA or NPA (I know NPAs have an MDA - before anyone jumps on that).

I'd write more but I'm using a knackered keyboard in an airport lounge with very slow internet, so my enthusiam is waning! Besides, I hung up my flying suit yesterday, so what do I know anymore! :ok:

Non-PC Plod

1st Aug 2013, 10:06

Thanks for all the posts so far.
For those flying across the water, please note what I said in the original post - the problem does not arise in the States, because NPAs are still published by Jeppesen in the traditional format. The problem is in Europe, where these approaches have been replaced.
I can see there is real split opinion in this community, which reflects the situation I have at work. We can see the advantages and disadvantages of flying with CDFA, and with the "dive and drive". We know how we have flown in the past, and what technique we like. BUT.... what is legal? - If a published approach is depicted with a CDFA and a DA, can we unilaterally decide to "dive and drive" and elect to treat the published DA as an MDA?
Is there anybody out there from EASA/CAA etc with a definitive answer?

[email protected]

1st Aug 2013, 10:44

212man - what is easier, fly a level last 1/2nm with the height hold in following the crappy NDB in marginal weather looking for the references or flying a constant descent to 50' above the MDA and then having to initiate the go around?

I don't personally like the full dive and drive profile and we tend to do what I was advocating earlier - the difference between it and a CDFA approach is that you get to MDA and level before the MAPt rather than fly a CDFA to the MAPt.

JimL is most likely to be the guy in the know as far as the 'legality' of how you fly it.

Stallion85

1st Aug 2013, 12:42

My "dive and drive" example is a little drastic. Just wanted to make my point clear. I prefer a smooth decent too. But when the weather is critical I wan't to be at the MDA as soon as possible.

but dooes not meet the 'Required Visual References' criteria
I might be wrong on this, but when I have the "requested" 2,5km (for example) at 650ft, runway environment in sight and in the circling area I meet the required visual references?

Similarly, your circling suggestion could be bad news - why weren't you visual before the MAPT? Maybe because the cloud was thicker and lower before that point, and now you are turning and descending towards it! With broken cloud, there is always the possibility of encountering that unwanted 'okta' at the...

Of course, this possibility does exist.
But in the real world you probably have the actual weather at the aerodrome from the ATIS or TWR. The location of the TWR controller is most likely very near at the MAPt (near the runway) so he should be able to give you a pretty clear picture of the weather and therefore the possibility to get IMC or not during circling.
And again... we are flying helicopters. Circling is not a traffic pattern.
It could also mean that the approach is not aligned with the runway, so I wouldn't need to turn back into IMC.

Back to the legal stuff, DA or MDA:
Non PC-Plod, could you post a picture of the chart?
Haven't seen one of those approaches before.

hihover

1st Aug 2013, 13:18

Plod -

I have not seen a published approach where a non-precision approach, depicted with CDFA, has a Decision Altitude (DA). I would expect to see a published Minimum Descent Altitude (MDA) as it is non-precision.

As far as I am aware, the legal bit is clear, at a DA(Precision Approaches) a decision is required, and if a go-around is the decision then you will descend below that DA quite legally during the process. The MDA(Non-precision approaches) is the MDA, and is a not-below altitude unless you have the required references.

There are exceptions to these under certain circumstances, but in general, this is the legal situation as I see it.

HH

SASless

1st Aug 2013, 13:20

Which type of NDA are we talking about here?

The NDA is just that.....Non-Precision.

Legally, (at least in the USA), you can descend to the MDA at the FAP and fly the final approach at that altitude. That method is generally frowned upon by most.....whereas the descend expeditiously so as to arrive at MDA slightly before the MAPT.

We have to discuss what determines the MAP.....a Beacon or Time....before we can adequately discuss the methodology of using a Vertical Descent Criteria, in my view.

If using an approach where the MAPT is a Beacon then Vertical Guidance might well be appropriate. If the Beacon is behind you.....and Time is the determining factor....we would have to rethink what we are trying to achieve.

I prefer to get down to the MDA and fly at MDA to the Missed Approach Point....with the goal of getting visual in time to locate the point of landing, hopefully do so in a position to land straight in....or nearly straight in without having to circle to land. Remembering Circling to Land requires a higher MDA.

A NPA does not mean you will be aligned to the Runway in use.....and also does not mean the Airport will be in front of you.

Now that we have GPS.....knowing our position and track is much more precise even if limited to NPA use.

Which also begs the question.....are we talking about a GPS Overlay or GPS NPA?

Could we be a bit more precise about our Non-Precision?

Stallion85

1st Aug 2013, 13:31

This is out of the first linked doc:

5. APPLICABILITY. The FAA recommends CDFA for all of the following NPAs published with a vertical descent angle (VDA) or glideslope (GS):
• Very high frequency (VHF) Omnidirectional Range (VOR),
• VHF omni-directional range station/distance measuring equipment (VOR/DME),
• Non-directional radio beacon (NDB),
• NDB/distance measuring equipment (DME),
• Localizer (LOC), Localizer Back-Course (LOC-BC),
• LOC/DME,
• Localizer-type directional aid (LDA),
• LDA/DME,
• Simplified Directional Facility (SDF),
• SDF/DME,
• Area Navigation (RNA V), and
• Global Positioning System (GPS).

Outwest

1st Aug 2013, 23:43

I have a plate in PDF that shows this situation.....but I am not allowed to post attachments according to the little window below this screen.

SASless

2nd Aug 2013, 01:34

Some interesting reading......

http://aeronav.faa.gov/content/aeronav/acfstatus/RDs/10-01-229_Charting_CDFA.pdf

Another pprune discussion about this topic....

Jeppesen Approach Charts Non Precision DA (http://www.pprune.org/tech-log/441886-jeppesen-approach-charts-non-precision-da.html)

Non-PC Plod

3rd Aug 2013, 18:36

Sorry, I dont have access to a scanner just at the moment to put an example on here, but I may be able to do so next week. If you have access to Jeppesen charts, look at Rome Fiumicino LIRF for example. All the NDB, VOR and RNAV approaches have a DA, not an MDA. I say again, this is a European thing, and you dont see it in the States.
If JimL has an expert answer, it would be much appreciated!

army_av8r

4th Aug 2013, 15:24

it seems to me that when using the CDFA procedure. you are not flying the 3.0 angle down to the MAPt, at the MDA. you are flying the angle down to the Threshold. this will put you in a straight line down to the runway when you hit your MDA/DA, however, you will not be anywhere near the MAPt when you hit that target altitude. it seems to be the equivalent of shooting an ILS(with no G/S reference) but making your DH higher as if you were circling. instead of going missed at Station passage, time, or a given fix, you go missed at the MDA/DH. this makes every approach basically the same. you fly the prescribed decent rate based on the angle for the approach and your groundspeed.

Stallion85

5th Aug 2013, 07:01

t seems to me that when using the CDFA procedure. you are not flying the 3.0 angle down to the MAPt, at the MDA. you are flying the angle down to the Threshold. this will put you in a straight line down to the runway when you hit your MDA/DA,
only when the approach is aligned with the runway

however, you will not be anywhere near the MAPt when you hit that target altitude.
so I have to initiate a go around and wait for the MAPt to initiate the MAP...
And if the MAPt or DA is not at the runway I even do net have the time to have a lookout cause I have to initiate the climb immediately...
More complicated than before!

it seems to be the equivalent of shooting an ILS(with no G/S reference)
An ILS holds me aligned with the runway on a glideslope to make a landing from that position. Again, a lot of NPA procedures are not aligned.

but making your DH higher as if you were circling.
So in marginal weather my chance to get visual are reduced!

instead of going missed at Station passage, time, or a given fix, you go missed at the MDA/DH. Which is always higher / earlier than at the MAPt.
this makes every approach basically the same. you fly the prescribed decent rate based on the angle for the approach and your groundspeed.
THIS is exactly the problem. A precision is NOT the same as a NON Precision! I wait for the first one to confuse the new "DA" as a real DA. There is not much room left on your MAP underneath you!

The price we pay for "making every approach the same" is a higher DA/H or whatever you call it.
If I am IMC and wan't to land there, I want to go as low as possible in the approach to raise my chance to get visual.
Why should I fly a approach which makes it less likely to get out of the clouds?

Sorry, I still don't see the benefit. But maybe I'm just blind!

pilot and apprentice

5th Aug 2013, 11:03

Army_av8r: yes

Stallion: I think the struggle you are having is due to not having flown fixed-wing IFR. Even in the days before CDFA approaches, it was necessary, when flying an airplane, to have at least an awareness of when it was too late to try to land even if you got visual. A calculation was better but depended on navaids and other factors. In my day on jets, we calculated a VDP (visual descent point). It was not uncommon to be IMC at the VDP, visual later in the 'cruise' at MDA, and still be forced to finally O/S at the MAPt.

Getting oneself organized enough to plan a constant descent to arrive at the VDP at MDA set up for the 3 degree app was nice, realizing that going below MDA without being visual first was illegal.

Also, it is always a good idea to remember that legal and practical rarely align completely.

Given the different capabilities of airplanes and helicopters, the same approaches require different considerations.

The OP is just asking about the legality of how approaches must be flown given the current move to CDFA NPA plates. I'm sorry I don't have an answer for you but I strongly suspect, given the regulatory environment, that 'as published' is how they want you to go. Rotary flight is rarely considered when these decisions are made.

Non-PC Plod

5th Aug 2013, 13:39

I have referred this question to Flight Ops at the UK CAA - I will let you all know if they come back with a definitive answer.

Non-PC Plod

7th Aug 2013, 09:14

OK, here's the word from flight ops at the CAA:

The rules have been clearly laid down for aeroplanes in the Part 1 documentation
EASA have not really got round to doing the same properly yet for helicopters in the Part 3.
So - the bottom line legally is the rule that you may only an approach to an airport which has been approved by the State administering that airport.

If you know for certain that the airport where you are landing has a "traditional style" non-precision approach published in the AIP, then of course you can fly it. (Of course you should also have a copy of the corresponding approach chart in your hand!)
If you dont know for sure that the state controlling the airport has specifically authorised it, then dont do it.
As we teach in the simulator to clients from dozens of different countries, and we cant know all the individual differences, the safest option is to say:

1. Make sure you have the correct approach chart.
2. Fly the profile depicted on the chart

Simple, really!

That is the line I am going to take - of course anyone who disagrees should take it up with their flight ops inspector, and see what he says.

hihover

7th Aug 2013, 10:25

Thanks Plod. Interesting topic actually. I had not noticed the creeping changes from here in the sandbox and your original question prompted me to do some digging.

You don't know what you don't know, until someone brings it up.

HH

SASless

7th Aug 2013, 17:44

Out of all this I was surprised to see the FAA being willing to follow the lead of European authorities on this.

Aynayda Pizaqvick

14th Sep 2013, 13:55

Non-PC Plod,

Thanks for asking the question to CAA and sharing their response as that has confirmed my understanding of things from EU Ops 1 subpart E:

All non-precision approaches shall be flown using the continuous descent final approaches (CDFA) technique unless
otherwise approved by the Authority for a particular approach to a particular runway.

Edit: note that EU Ops 1 is fixed wing... still trying to work out the definitive answer for helicopters...

Basically, unless the approach plate specifically states that it is a non-CDFA approach (eg NDB at Norwich and Manston) then you don't get a choice whether to choose to fly the "dive and drive" technique, you must use the CDFA technique, regardless of if the minima for the NPA are depicted as a MDA or DA.

army_av8r makes an important point - you should be planning your descent to the runway threshold, NOT to the beacon, after all you should be planning to continue your approach to land to a long strip of tarmac, not a bunch of aerials!

However I don't agree that this technique is the correct one for use by RW. If I know the weather is a bit rubbish and on the limits then I can reduce my approach speed to 60 kts and normally make an unhurried approach to the far end of the runway if I need to. If the above is CAA's view then they need to have a think about the specific needs of the RW community and not try apply a once size (doesnt) fit all rule.

[email protected]

14th Sep 2013, 22:08

Thoroughly agree - this concept has been driven by the FW world (for good reasons) but is wholly unsuited to the more flexible world of RW ops.

keithl

15th Sep 2013, 18:11

Some believe that you can still fly this approach in a helicopter in the "traditional" manner, treating the DA as an MDA. Others say that you must fly it as published on the chart. There is debate as to whether there should be a helicopter type allowance to add on before it is acceptable to fly it as a DA.

Just one small fact that I don't think anyone has mentioned yet, NPCP, in UK CDFA was made mandatory for FW in 2011, but not for RW, who are still free to fly non-CDFA. If I were at work, I'd get you the number of the Safety Notice, but I'm on hols soon for a couple of weeks. CAA website, search on S/Ns 2011.

Aynayda Pizaqvick

15th Sep 2013, 22:20

Right, armed with Keiths words I've done a bit of digging and... basically got nowhere!

This safety notice http://www.caa.co.uk/docs/33/SafetyNotice201103.pdf states "...Public Transport and Private operators should also use the CDFA technique for NPA operations wherever possible." so would imply we SHOULD use it but may (I would reason such as when doing so might limit our chances of gaining the required visual references) use the dive and drive technique.

http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2012:296:0001:0148:EN:PDF this however only references CDFA for aeroplanes (CAT.OP.MPA.115) so would it be reasonable to assume from that the safety notice has been superseded by the newer regulations? I have no idea so have sent another email to CAA asking them to clear it up with some authoritative guidance... I shall share any response I get.

keithl

16th Sep 2013, 12:16

Its SN 2011-03 dated 6 May 2011, entitled "Aerodrome Operating Minima".

Refers to "EU-OPS 1" and "aeroplanes", therefore strictly FW.

May well have been subsumed into legislation.

switch_on_lofty

6th Oct 2013, 21:53

Any joy from the CAA on CDFA?

Aynayda Pizaqvick

7th Oct 2013, 18:08

Nope, nothing. I seem to have been well and truly ignored!! I may have to try sending it to multiple addresses and see if I get anywhere.

Aynayda Pizaqvick

9th Oct 2013, 20:03

Ok, got a response following a subsequent email, seems it was an internal email forwarding error rather than them ignoring me! It is only an interim response that ultimately doesn't clear much up so I'll hold off posting it until I have their final word.

SASless

9th Oct 2013, 23:41

Now that is rich....."The Final Word" from the CAA.:rolleyes:

inbalance

10th Oct 2013, 14:57

Here are 2 samples of NP approaches in germany.
You have to fly them as CDFA, because they don´t have a published MAP.

http://img266.imageshack.us/img266/5734/nkvo.jpg

http://imageshack.us/a/img571/953/r1u8.jpg

Inbalance

AnFI

10th Oct 2013, 18:03

not sure I understand - you say they have not got a MAP ?

[and I thort MAP and MAPt were different things (Proceedure and Point)]

can a knowing person please clarify for me.

looks to me that those plates have both ?

do you mean they have DA instead of MDA ?

inbalance

10th Oct 2013, 18:11

My mistake,
they don´t have a MAPt.

Inbalance

RedWhite&Blue

10th Oct 2013, 20:22

The first plate says MAP at RW25 the second MAP at D0.5 MOD if my eyes don't deceive me.

RedWhite&Blue

11th Oct 2013, 08:16

Non-PC Plod

I think 212man had the answer to your original question about the source of the chapter and verse you want, if not the reference itself.

By the way I have included the definition of MAP as some people may be expecting it to be MAPt.

Try

PANS OPS Flight Procedures (Doc 8168)

3.6.1.3
The missed approach point (MAP) in a procedure may be:
a.the point of intersection of an electronic glide path with the applicable DA/H; or
b.a navigational facility; or
c.a fix; or
d.a specified distance from the final approach fix (FAF).
When the MAP is defined by a navigational facility or a fix, the distance from the FAF to the MAP is normally published as well, and may be used for timing to the MAP. In all cases where timing may not be used, the procedure shall be annotated “timing not authorized for defining the MAP”.

1.6.2
Operators may specify two types of approach procedures for non-precision approaches. The first is that described as: “descend immediately to not below the minimum stepdown fix altitude/height or MDA/H as appropriate”. This method is acceptable as long as the achieved descent gradient remains below 15 per cent and the missed approach is initiated at or before the MAP. Alternatively, operators are encouraged to use a stabilized approach technique for non-precision approaches. This technique requires a continuous descent with a rate of descent adjusted to achieve a constant descent gradient to a point 15m (50 ft) above threshold, taking due regard of the minimum crossing altitudes/heights specified for the FAF and any prescribed stepdown fix. If the required visual reference approaching MDA/H is not achieved, or if the MAP is reached before reaching the MDA/H, the missed approach must be initiated. In either case, aircraft are not permitted to go below the MDA/H at any time. The stabilized approach technique is also associated with operator-specified limits of speed, power, configuration and displacement at (a) specified height(s) designed to ensure the stability of the approach path and a requirement for an immediate go-around if these requirements are not met.

Hope that helps.

Non-PC Plod

11th Oct 2013, 09:42

Aser

11th Oct 2013, 10:25

Red White & Blue,

Thanks - its good to have a definition from an authoritative source. BUT.....

"In either case, aircraft are not permitted to go below the MDA/H at any time"

It is still not clear how you comply with this if a MDA/H is not published, only a DA!

Operators on a Non-Precision Approach in Europe should note:

On a Non-Precision Approach, the airplane must never descend below the published minimum altitude during the initiation of the missed approach.
Unlike DA(H) minima published on an ILS, LNAV/VNAV, or LPV procedure, the DA(H) minima for the subject Non-Precision approaches (e.g., LOC, VOR, LNAV, NDB) published by Jeppesen do not provide an allowance for any momentary altitude loss during the transition to the missed approach climb.

Therefore, when a DA(H) is shown by Jeppesen on a Non-Precision Approach chart, it is critical to safety that crews account for loss of altitude in order to avoid descent below the published DA(H).
The value of the additive is left to the discretion of the operator, but should reflect realistic operating characteristics of the aircraft as well as crew performance.
Notice to Operators Flying European Non-precision Approaches | NBAA - National Business Aviation Association (http://www.nbaa.org/ops/intl/eur/20110217-europe-non-precision-approaches-cdfa.php)

Regards
Aser

RedWhite&Blue

11th Oct 2013, 10:25

Ok,

Definitions from Doc 8168

Decision altitude (DA) or decision height (DH). A specified altitude or height in the precision approach or approach
with vertical guidance at which a missed approach must be initiated if the required visual reference to continue the
approach has not been established.
Note 1.— Decision altitude (DA) is referenced to mean sea level and decision height (DH) is referenced to the
threshold elevation.
Note 2.— The required visual reference means that section of the visual aids or of the approach area which should
have been in view for sufficient time for the pilot to have made an assessment of the aircraft position and rate of change
of position, in relation to the desired flight path. In Category III operations with a decision height the required visual
reference is that specified for the particular procedure and operation.
Note 3.— For convenience where both expressions are used they may be written in the form “decision
altitude/height” and abbreviated “DA/H”.

Minimum descent altitude (MDA) or minimum descent height (MDH). A specified altitude or height in a nonprecision
approach or circling approach below which descent must not be made without the required visual
reference.
Note 1.— Minimum descent altitude (MDA) is referenced to mean sea level and minimum descent height (MDH) is
referenced to the aerodrome elevation or to the threshold elevation if that is more than 2 m (7 ft) below the aerodrome
elevation. A minimum descent height for a circling approach is referenced to the aerodrome elevation.
Note 2.— The required visual reference means that section of the visual aids or of the approach area which should
have been in view for sufficient time for the pilot to have made an assessment of the aircraft position and rate of change
of position, in relation to the desired flight path. In the case of a circling approach the required visual reference is the
runway environment.

So we know on a non precision aproach we fly to MDA/H. Not a DA/H!

Thus, the question should be to the agency who publish the plate why they have printed the wrong term in the minima box, should it not?

Aser

11th Oct 2013, 11:52

There is nothing "wrong"

AERODROME OPERATING MINIMUMS ACCORDING TO EU-OPS 1
General Information
The European Union published the 2nd Amendment of EU-OPS 1 (Annex III to Regulation 3922/91).
http://eur-lex.europa.eu/JOIndex.do?ihmlang=en
This EU-OPS 1 is the replacement of JAR-OPS 1 and contains a new method to determine Aerodrome Operating
Minimums (AOM). The new method will become the European Standard on 16 July 2011 at the latest.
According to ICAO Doc 9365-AN910 (Manual of All Weather Operations) and Annex 6 to the Convention on
International Civil Aviation it is the ope
rator’s responsibility to establish Aerodrome Operating Minimums which
need to be approved by the responsible authority.
The Appendix 1 (new) to OPS 1.430 describes the method which has to be used by all European Operators and
within the European Union (EU).
Jeppesen will support your operations by replacing the current JAR-OPS AOM with the new Standard. Due to
the huge number of airports (1000+) and pro
cedures (5000+) the conversion could only be done on a step by
step basis.
It is our intent to have all procedures revised to the new Standard AOM by 16 July 2011 for all airports within
– European Union member states,
– European Aviation Safety Agency (EASA) member states,
– Joint Aviation Authorities (JAA) member states and
– for other states where the currently used JAR-
OPS AOM will be replaced.
In May 2008 we asked commercial operators about their plans for this EU-OPS implementation. The following
items are directly related to the result
s of that survey:
a. All non-precision approaches will be reviewed to show CDFA (Continuous Descent Final Approach) profile
and minimums.
b. In case of CDFA only, a DA(H) is shown instead of the previously published MDA(H). The missed approach
point is still shown according to state so
urce but the missed approach initiation arrow is moved to the point
where the DA(H) is reached.
c. Jeppesen charted AOM do not include an add
-on when current MDA(H) is replaced by DA(H). Pilots are
reminded to check their operator’s Flight Operations Manual or similar documents whether they have to
apply an add-on or not.
d. For CDFA profiles, Jeppesen will show DME vs altitude bands, distance vs altitude bands or timing vs
altitude tables. If not provided by the State source those altitudes will be calculated by Jeppesen.
e. Non-CDFA profiles and minimums will be shown in exceptional cases only and may be combined with CDFA
profiles and minimums.
f. For CAT I operations with full approach light system (FALS) Jeppesen will include RVR values below 750m
together with the higher values. Pilots are reminded to check their operator’s Flight Operations Manual or
similar documents to fulfill the require
ments for using the lower RVR values.
g. Lower than standard CAT I minimums are charted on request on customer tailored charts.
h. Other than standard CAT II minimums will be charted if the procedure is approved for such operations by
the state of the airport.
i. Circling minimums must not be lower than the minimums of preceding instrument approach procedure. If
circling MDA(H) and/or visibility must be raised due to higher straight-in values, only one set of circling
minimums is shown which relates to th
e highest straight-in minimums.
Legend and ATC Pages
Jeppesen is currently reviewing the final version of this EU-OPS to replace the current ATC-601 (JAA AOM)
pages with a summarization of the new EU-OPS Aerodrome Operating Minimums.
In addition we will update the current Introduction 171 – 173 (JAR-OPS 1 AOM) pages to explain how the new
minimums and the CDFA profiles are dep
ictedonJeppesencharts.
Conversion Plan
The publication of the new Standard of AOM will be done along with normal chart revision activity. It is planned
to convert all procedures of an affected airport at the same time.
We will create special minimums pages, numbered 10-9S (similar to current 10-9X JAR-OPS pages), as an
interim solution.
Jeppesen will maintain or create JA
R-OPS 1 minimums pages on customer request only.
Please contact your Jeppesen custo
mer service representative for any special requirements, such as airline
tailored minimums, airborne equipment considerations or your conversion priorities.
q$z
RETAIN THIS BULLETIN UNTIL ADVISED TO DESTROY
©
JEPPESEN, 2
008. ALL RIGHTS RESERVED.
JEP 08-D1
26 SEP 08
BRIEFING BULLETIN
AERODROME OPERATING MINIMUMS ACCORDING TO EU-OPS 1
q$i
Charts with JAR-OPS label
The JAR-OPS label on Jeppesen approach and airport charts indicates that the minimums correspond to the
rules described in Appendix 1 (old) to OPS 1.430 of the EU-OPS 1.
Future Outlook
The FAA will also publish new minimums wh
ich will be harmonized with the EU ones.
Jeppesen’s intention is to replace the c
urrent ECOMS and JAR-OPS Aerodrome Operating Minimums with the
future harmonized version on a world-wide basis.

RedWhite&Blue

11th Oct 2013, 12:28

Aser,

Part of this thread has been formed by the confusion created by the use of the term DA/H on a Non Precicion proceedure.

While I accept that Jepp have published a guide to how their plates are presented the presentation seems in conflict with PansOps.

I guess PansOps is the higher authority as it lays down how Instrument proceedures are designed and flown.

Whether flying CDFA or Dive and Drive why are the mimima not published in line with PansOps?

Something seems 'wrong' to me. Hence the confusion in this thread.

I'm sure Jepp have very solid reasoning for their depiction but no doubt it has created confusion.

AnFI

11th Oct 2013, 15:38

Annex to ED Decision 2012/018/R
Quote:

(3) When reaching the published instrument MAPt and the conditions stipulated in
(c)(2) are unable to be established by the pilot, a missed approach should be
carried out in accordance with that instrument approach procedure

So MAPt in EU land:

Annex to ED Decision 2012/018/R
or
see Eurocontrol's Skybrary: SKYbrary - Missed Approach (http://www.skybrary.aero/index.php/Missed_Approach)

Also it has to be said
A) It's a bit of a worry that there exist several interpretations and understandings of this stuff.
B) Jeppesen need to think about the confusion this causes even if they do cover it in their interpretation document.

Regulations should be simple, clear and consistent. Still the pass mark is only 75% so presumably pilot's don't need to know 25% of this stuff anyway?

212man

11th Oct 2013, 15:57

The term DA is not restricted to Precision Approaches - it is applicable to other approaches with "Vertical Guidance". Although a CDFA can be flown without vertical guidance (using range/altitude fir example) it may be that the approaches that Jeppesen are producing with DAs depicted are also the approaches for which they provide Vertical encoding in their Nav Data subscriptions for FMS/FMC/FMGS etc.

AnFI

11th Oct 2013, 16:34

ICAO Doc 8168 v2
Missed approach point (MAPt).
That point in an instrument approach procedure at or before which the prescribed
missed approach procedure must be initiated in order to ensure that the minimum obstacle clearance is not
infringed.
Missed approach procedure.
The procedure to be followed if the approach cannot be continued

Aser

11th Oct 2013, 20:35

As it says in the Jepp. doc. :
The European Union published the 2nd Amendment of EU-OPS 1 (Annex III to Regulation 3922/91).
http://eur-lex.europa.eu/JOIndex.do?ihmlang=en
This EU-OPS 1 is the replacement of JAR-OPS 1 and contains a new method to determine Aerodrome Operating
Minimums (AOM). The new method will become the European Standard on 16 July 2011 at the latest.I'm not flying in Europe, but if you take a look to EU-OPS 1 (and that is now the law) you will find:

OPS 1.430
Aerodrome operating minima — General
(See Appendix 1 (old) and Appendix 1 (new) to OPS 1.430)

(d)1. All approaches shall be flown as stabilised approaches (SAp) unless
otherwise approved by the Authority for a par-
ticular approach to a particular runway.

(d)2. All non-precision approaches shall be flown using the continuous de
scent final approaches (CDFA) technique unless
otherwise approved by the Authority for a particular approach to a particu
lar runway.

Appendix 1 (New) to OPS 1.430
Aerodrome operating minima

(b) Category I, APV and non-precision approach operations

2. A non-precision approach (NPA) operation is an instrument approach usi
ng any of the facilities described in Table
3 (System minima), with a MDH or DH not lower than 250 ft and an RVR/CMV of not l
ess than 750 m, unless accepted by the Authority.

9. “Continuous descent final approach (CDFA)”. A specific technique for f
lying the final-approach segment of a non-
precision instrument approach procedure as a continuous descent, withou
t level-off, from an altitude/height at or above
the Final Approach Fix altitude / height to a point approximately 15 m (50 fe
et) above the landing runway threshold
or the point where the flare manoeuvre should begin for the type of aeroplan
e flown.

10. “Stabilised approach (SAp)”. An approach which is flown in a controlle
d and appropriate manner in terms of configu-
ration, energy and control of the flight path from a pre-determined point o
r altitude/height down to a point 50 feet
above the threshold or the point where the flare manoeuvre is initiated if h
igher.

I don't see anything wrong with the Jeppesen explanation. Better check with your operator and start flying CDFA using add-on height to the DA...

Regards

[email protected]

11th Oct 2013, 20:58

Not if you are a helicopter pilot - EUops1 is for FW.

Non-PC Plod

11th Oct 2013, 21:24

Isnt it funny how we keep going round in this circle? It really emphasises the fact that EASA has done a p**ss poor job of letting us all know what we should be doing. There are a lot of experienced people on rotorheads - many of us are teaching this stuff. We cant even get a straight answer from our own national authorities.
Can anyone else see James Reason's slices of emmenthal starting to align themselves?

SASless

11th Oct 2013, 22:32

EASA has done a p**ss poor job of letting us all know what we should be doing.

At some point does the Industry need to tell EASA what to do?

Aser

12th Oct 2013, 02:00

Crab you are right, I know eu-ops 1 is for fix wing.
But if want to fly a non-precision app with a jepp. chart and there is only a CDFA profile with no map on that specific chart... then what?

a) Don't use it, keep non-jepp charts on board.
b) Read eu-ops 1, learn what a cdfa is, get the operator to stablish a DA for the app. and get ready for the replacement of jar-ops 3.

Some people said here that we can't have a DA in a non-precision app, well I prefer to read fixed wing stuff and not get confused...

Or do you mean we can't fly a cdfa profile in a helicopter?

regards!

Aynayda Pizaqvick

12th Oct 2013, 10:55

So this is where I have got with all this this week (all information pertinent to helicopters only)....

CAA say that the option to fly CDFA or non-CDFA "rests with operators, assuming the approach designer does not prohibit non-CDFA."
Having spoken to the approach designer (NATS) PANS-OPS does not prohibit or allow CDFA or non-CDFA approaches as it is an operator’s consideration, not an approach design consideration. There aren't separate design criteria/rules that are applied if an approach is going to be CDFA or non-CDFA, the approach designer simply applies the PANS-OPS rules to provide the minimum obstacle clearance etc. So, provided you fly the approach above the step heights and minima then you are safe.
Take the NATS plate for NDB 27 Norwich as an example http://www.ead.eurocontrol.int/eadbasic/pamslight-9F1FF00EA8FD9FD8F2D421BA5EC45A18/7FE5QZZF3FXUS/EN/Charts/AD/AIRAC/EG_AD_2_EGSH_8-6_en_2011-06-30.pdf It makes no mention of CDFA (the charts our operators provide give separate CDFA and non-CDFA minima for this procedure) which backs up the approach designers claims that it isn't a design consideration. In my honest opinion (and I am most definitely NOT an authority on this) we can therefore chose to use either technique and just obey the step heights and minima on the plate.

The CAA appreciate that we could do with some info/guidance and are trying to arrange the publication of a CAA Information Notice to help get the message out. Not sure if it will have the information from the approach designer though as that was my own leg work. Finger crossed that has helped someone!?

Non-PC Plod

12th Oct 2013, 12:25

Seems to make sense, the only question I still have, is how you to find your MDA if you are doing the old fashioned technique on an approach with a plate that only depicts the CDFA? If you only have a DA to go on, because there is no obstacle clearance altitude info on the plate, do you just treat the DA as an MDA, and accept that you are going to be at least level with, if not above the actual OCA?

RedWhite&Blue

12th Oct 2013, 13:17

Aynayda Pizaqvick,

I agree with you.

Non-PC Plod - Exactly my thoughts!

Style of approach is down to the operator as defined by PANS Ops (see my post #40). Note PANS Ops is not only the design standard but it also tells us the basics of how to fly the proceedures - if one has the energy to pick the bones out of it!

However, what we still have not solved is why Jepp have chosen to difine the minima on a CDFA NPA as a DA/H.

We know as with any NPA, if you choose to fly CDFA, you must not descend below MDA/H until you have the cues to continue visually.

I get that the operator must apply a factor to MDA/H depending on aircraft performance to create a Derived Decision Altitude (DDA) to ensure that the aircraft dosen't dip below MDA/H on Go Around.

Therefore, do you not need to know, from the plate, the MDA/H to which you add your company/aircraft factor in order to derive a DDA/H? Does PANS Ops not require a OCH/A to be published for each aproach proceedure? Look at your example of Norwich NDB 27 from the UK AIP and you can see they are published. Clearly this is not drawn as CDFA but the OCA/H is published.
I can't view the jepp plates from a few posts ago so I have no ref right now to compare.

I notice that the FAA say Operators conducting approaches authorized by operations specification (OpSpec) C073, IFR Approach Procedures Using Vertical Navigation (VNAV), may use MDA as a DA.

Do we take from this, that Jepp assume this to be the case and that their DA is in fact a true MDA/H that we could apply to Heli ops.

As we all know "assumption is the mother of all..." but it is a line of enquiry.

Aynayda Pizaqvick

13th Oct 2013, 10:49

I don't use Jepp plates so not in a position to comment. Wouldn't it make life easier though if they applied one logic for all plates and approach types i.e. just write the absolute minima which you cannot go below without the required visual references?
Presumably whoever decided that we can dip below DA on an ILS has already built in some fat to make sure that we are safe/don't hit anything during the go around and presumably they applied a worst case scenario to allow for anything from cessnas to Jumbos. If we are coming up with our own derived DA for NPA (or hopefully not given the information above) surely they can just give us the absolute minima so that each aircraft type can build in a suitable factor to stay above the minima and get us down as low as safely possible? A common solution that caters for a vast array of aircraft types.

RedWhite&Blue

14th Oct 2013, 14:08

I was looking for something on a totally different subject when I stumbled across this.

It is from EASA Annex to ED Decision 2012/018/R and is offered to us as Acceptable Means of Compliance and Guidence Material.

AMC3 CAT.OP.MPA.110 Aerodrome operating minima
NPA, APV, CAT I OPERATIONS
(a) The decision height (DH) to be used for a non-precision approach (NPA) flown with the continuous descent final approach (CDFA) technique, approach procedure with vertical guidance (APV) or CAT I operation should not be lower than the highest of:
(1) the minimum height to which the approach aid can be used without the required visual reference;
(2) the obstacle clearance height (OCH) for the category of aircraft;
(3) the published approach procedure DH where applicable;
(4) the system minimum specified in Table 3; or
(5) the minimum DH specified in the aircraft flight manual (AFM) or equivalent document, if stated.

(b) The minimum descent height (MDH) for an NPA operation flown without the CDFA technique should not be lower than the highest of:
(1) the OCH for the category of aircraft;
(2) the system minimum specified in Table 3; or Annex to ED Decision 2012/018/R
(3) the minimum MDH specified in the AFM, if stated.

So here's a question - What do you do if you fly CDFA without APV?

Aser

14th Oct 2013, 22:19

So here's a question - What do you do if you fly CDFA without APV?

Fly the required rate of descent.

RedWhite&Blue

15th Oct 2013, 08:04

Aser,

If you have a Jepp chart with a published DA/H will you know the MDH for your cat of aircraft? (I can't see a Jepp plate right now to compare. I guess it may be listed on a seperate Heli ops Minima Page for the Aerodrome).

If you can only fly a DH by uing APV and only MDH/A without APV what minima will you descend to when flying CDFA at the "required rate of descent"?

Aser

15th Oct 2013, 16:50

Aser,

If you can only fly a DH by uing APV and only MDH/A without APV what minima will you descend to when flying CDFA at the "required rate of descent"?

I think your may be confused by your previous post
(a) The decision height (DH) to be used for a non-precision approach (NPA) flown with:

-the continuous descent final approach (CDFA) technique,

-approach procedure with vertical guidance (APV),

-or CAT I operationAre 3 different things...

You can fly a CDFA (using the DA/H) technique with or without vertical guidance.

If you choose not fly the cdfa (I'd suggest not to use charts with cdfa only profiles then), I guess you can always use the DA as MDA.

Take a look to this side by side charts:
http://www.terps.com/EHAM/EHAM%20Side%20by%20Side.pdf

Regards
Aser

RedWhite&Blue

15th Oct 2013, 21:54

Aser

Thanks for that - I think I've got it now!

Simples

Non-PC Plod

16th Oct 2013, 20:07

Aser,

Thats useful - the DA and the MDA are shown as the same for the 2 styles of approach. Hopefully what I have been teaching has been correct as luck would have it! Unfortunately at the airport where we practise most IFR approaches in simulator training, there are only CDFA approaches to go on, yet some operators want to use the traditional style.

Geoffersincornwall

17th Oct 2013, 07:37

IMHO the best solution when teaching how to manage the FMS you have to take account of the CUSTOMERS own day-to-day operations. This teaching process is very context sensitive. The way you use the FMS/AP/FD to manage the altitude will be different according to the requirements of the CUSTOMER'S jurisdiction and you don't have much time to get more than one solution across given the parlous IFR skill levels we encounter.

If it's possible to do the IFR section at the customer's local airport then this option should be considered if the outcome would be more favourable. The problem with this solution is that the simulator and it's software are so flakey that 50% of the time moving away from the tried and tested Rome runways ends in a disastrous capitulation to the Lord of the Windows (thank you Bill!!!)

Irrelevant training is almost a total waste of time - even though it may facilitate the ticking of a box - so the more relevant we can make a lesson the greater value it creates. If the customer works in an environment where 'dive and drive' is 'de rigour' there seems little point in teaching him an alien procedure he may never use. Notice that I used the word 'teach' rather than 'deliver'. There's a little too much 'delivering' going on out there and not enough 'teaching. I think you will agree that teaching requires the SFI to be able to recognise, understand and deal with the customer's faults and shortcomings rather than just tick-boxing your way through a list of manoeuvres.

G.