IFR Procedural Q
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IFR Procedural Q
I would like to know what guidance/limitations your companies give you when considering flying a IFR procedural approach. In my experience having trained many pilots from other airlines, different operators advocate different ideas. For example, does your operator allow you to pick up a procedure at the CF providing it is above MSA? In other words cutting out part of a procedure providing you remain within protected airspace and above MSA. Obviously this saves much time and fuel and could be argued is safe, but would you legally be allowed to do this? I have seen many pilots doing exactly that and find it difficult to argue against it, especially when ATC (usually Italian) promote it for their own efficiency of movements in a non radar environment.
Another question is, if you end up flying to an airport not contained within the NAV database and you end up having to build an approach using place/bearing/dist etc. what guidelines does your company give as to whether you can use LNAV or not? And what emphasis does the crew make re raw data backup? I am only really interested in IRS/GPS updated FMC a/c operators i.e. capable of RNP <1.
When approaching a beacon to go out bound, do you have to be level at the procedure ALT or can you go into the procedure in a constant descent, again from a fuel efficiency point of view. Obviously with ATC permission, but I would like to know what is the legal standpoint from an IFR point of view.
Finally, to go outbound straight into a procedure you must be within 30 degrees of the outbound course. Does your airline allow you to position the a/c, again above MSA, to allow to go straight outbound by making the needle drop into the 30 degree range. What do you as a examiner think of this practice?
Is there a good website to find the answers to all these questions.
Thanks.
Another question is, if you end up flying to an airport not contained within the NAV database and you end up having to build an approach using place/bearing/dist etc. what guidelines does your company give as to whether you can use LNAV or not? And what emphasis does the crew make re raw data backup? I am only really interested in IRS/GPS updated FMC a/c operators i.e. capable of RNP <1.
When approaching a beacon to go out bound, do you have to be level at the procedure ALT or can you go into the procedure in a constant descent, again from a fuel efficiency point of view. Obviously with ATC permission, but I would like to know what is the legal standpoint from an IFR point of view.
Finally, to go outbound straight into a procedure you must be within 30 degrees of the outbound course. Does your airline allow you to position the a/c, again above MSA, to allow to go straight outbound by making the needle drop into the 30 degree range. What do you as a examiner think of this practice?
Is there a good website to find the answers to all these questions.
Thanks.
Well, Jambo, over a day and 144 views with no reply. I was avoiding replying because I don't qualify on your
criteria. However, I think you've raised an interesting question and maybe my reply will provoke more response than your Q.
The CF is not part of an instrument procedure, of course. I saw something in an AIC I think, to that effect. But I often wonder, myself, why one shouldn't join the O/B leg of a procedure (providing, as you say, one is above MSA) without starting at the IAF. Once established on the procedure one can then descend according to it. Like you, I can't see why not.
OzExpat may have a view on this.
"Self positioning" to achieve the <30deg is, in my outfit's policy, perfectly OK provided ATC are happy with it. As an ex-examiner, I would say this demonstrated good awareness of both the situation and the rules.
Now, let's see if that draws a response...
I am only really interested in IRS/GPS updated FMC a/c operators i.e. capable of RNP <1.
The CF is not part of an instrument procedure, of course. I saw something in an AIC I think, to that effect. But I often wonder, myself, why one shouldn't join the O/B leg of a procedure (providing, as you say, one is above MSA) without starting at the IAF. Once established on the procedure one can then descend according to it. Like you, I can't see why not.
OzExpat may have a view on this.
"Self positioning" to achieve the <30deg is, in my outfit's policy, perfectly OK provided ATC are happy with it. As an ex-examiner, I would say this demonstrated good awareness of both the situation and the rules.
Now, let's see if that draws a response...
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Staying above MSA means (ATC/airspace permitting) you can route pretty much anywhere. If you then establish on a procedure then fine, once on a procedure then I see no problems descending to the procedural alt.
Our lot do not allow the use of any FMC procedure that is pilot constructed below MSA. We still punch it in as advisory, but are not allowed to follow it either on MAP or LNAV. Raw data rules!
Our lot do not allow the use of any FMC procedure that is pilot constructed below MSA. We still punch it in as advisory, but are not allowed to follow it either on MAP or LNAV. Raw data rules!
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Keithl,
Yes I was wondering if it was a boring subject or whether there might be a little uncertainty out there. Actually my RNP<1 statement is probably a red herring as most FMC's with radio updating will easily do RNP<1. With the advent of PRNAV on our doorstep (RNP<1 capability), times are changing with RNAV SID's and STAR's becoming available and I hope some easy to understand definitions might be available as guidance.
I really don't know, as an examiner, what I would do if the crew I was checking were to do a little self positioning above MSA. Of course there are good crews who would make sure they were dotting the I's and crossing the T's, then you have the less proficient crews who are just looking for time saving techniques with less respect of terra firma.
I guess common sense again is the answer, but legally?
Yes I was wondering if it was a boring subject or whether there might be a little uncertainty out there. Actually my RNP<1 statement is probably a red herring as most FMC's with radio updating will easily do RNP<1. With the advent of PRNAV on our doorstep (RNP<1 capability), times are changing with RNAV SID's and STAR's becoming available and I hope some easy to understand definitions might be available as guidance.
I really don't know, as an examiner, what I would do if the crew I was checking were to do a little self positioning above MSA. Of course there are good crews who would make sure they were dotting the I's and crossing the T's, then you have the less proficient crews who are just looking for time saving techniques with less respect of terra firma.
I guess common sense again is the answer, but legally?
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APP rules
I did an Aussie IR first where the rules were explicit - you can not join an instrument approach after the published IAF. There may be an IAF indicated at or near the CF. You can manouver as required above the MSA inorder ot intercept the required course at the IAF (by <30deg). Also no IFR approaches allowed below MSA where no published procedure exists (regardless of accuracy).
I have never found any explicit advice in the JAA regs but maybe I didn't look hard enough. Perhaps this means that the default is the ICAO published rules, but who has the energy to read these as well.
Perhaps posting this topic in the Instructor forum would generate more replies from the legal perespective.
I have never found any explicit advice in the JAA regs but maybe I didn't look hard enough. Perhaps this means that the default is the ICAO published rules, but who has the energy to read these as well.
Perhaps posting this topic in the Instructor forum would generate more replies from the legal perespective.
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I currently work in the US, and at the places I fly, it is pretty much a non issue, always vectored to final.
When I do my LPC in Norway, it is seen as lack of situational awareness not to join with in 30 deg. It is just all about how you do it, just make sure you get the clearance i.e. request 30 left/right to join the xxx QDR, as long as you are above the MSA I see no problem in it.
I know at places ATC will give similar instructions below MSA above MVA, when they do not feel like vectoring you…..especially when for practice ,you request something other than the ILS
When I do my LPC in Norway, it is seen as lack of situational awareness not to join with in 30 deg. It is just all about how you do it, just make sure you get the clearance i.e. request 30 left/right to join the xxx QDR, as long as you are above the MSA I see no problem in it.
I know at places ATC will give similar instructions below MSA above MVA, when they do not feel like vectoring you…..especially when for practice ,you request something other than the ILS
Jambo,
Not sure what P2 has added to the debate...
After a morning looking through PANSOPS and the UK AIP, I can only conclude that, from a legalistic point of view, the question simply isn't addressed. There is no legal answer to the question. That means that it can only be answered from a safety p.o.v.
Saint's experience may simply have been that these were IR rules rather than IF Procedural ones.
If that is the case, and always provided ATC are happy and you remain above MSA until established - I deduce it is OK!
Not sure what P2 has added to the debate...
After a morning looking through PANSOPS and the UK AIP, I can only conclude that, from a legalistic point of view, the question simply isn't addressed. There is no legal answer to the question. That means that it can only be answered from a safety p.o.v.
Saint's experience may simply have been that these were IR rules rather than IF Procedural ones.
If that is the case, and always provided ATC are happy and you remain above MSA until established - I deduce it is OK!
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I saw this topic when it was first posted but decided the same as you, keithl, that I wasn't sufficiently qualified to provide an answer. However, as to whether or not one can diverge from track sufficiently to get within the 60 degree sector (30 degrees either side), Pans Ops protects for this. However, if it's not in the State AIP (or regulations, or equivalent document) then you can't do it. Period.
This might be because the particular State has not bothered to apply the necessary additional protection area to accommodate it.
As for the matter of building your own approach in the FMC, that is not permitted here. And I'm pretty sure that nobody else permits it either. However, having said that, in the next couple of months, I'm hoping to run a trial that aims to allow this in a very limited way.
It will be based on the use of a GNSS receiver, manually configured to 0.3 NM HIL. If the trial proves to be successful, we will need to rewrite a few of our regulations to allow it. That process will be lengthy, so I don't expect it to come to fruitition much before the end of the year.
This might be because the particular State has not bothered to apply the necessary additional protection area to accommodate it.
As for the matter of building your own approach in the FMC, that is not permitted here. And I'm pretty sure that nobody else permits it either. However, having said that, in the next couple of months, I'm hoping to run a trial that aims to allow this in a very limited way.
It will be based on the use of a GNSS receiver, manually configured to 0.3 NM HIL. If the trial proves to be successful, we will need to rewrite a few of our regulations to allow it. That process will be lengthy, so I don't expect it to come to fruitition much before the end of the year.
Hi, OzEx I thought you'd get here sooner or later!
Yes, as far as the 30 deg either side goes we're all reasonably clear. You didn't address the other situation though - possibly deliberately. If you are close to the o/b leg of the procedure (but not on it) and would have to go out of your way to get back to the IAF (and then most likely have to turn around again to go o/b) why shouldn't you manoeuvre above MSA to establish somewhere along the o/b leg, and then descend to the the procedure altitude(s)?
Jambo and I seem to agree that there's nothing unsafe about that, but is there any prohibition in the legislation?
Yes, as far as the 30 deg either side goes we're all reasonably clear. You didn't address the other situation though - possibly deliberately. If you are close to the o/b leg of the procedure (but not on it) and would have to go out of your way to get back to the IAF (and then most likely have to turn around again to go o/b) why shouldn't you manoeuvre above MSA to establish somewhere along the o/b leg, and then descend to the the procedure altitude(s)?
Jambo and I seem to agree that there's nothing unsafe about that, but is there any prohibition in the legislation?
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Yes, well...
It was deliberate keithl! 
There MIGHT be a problem with the size of the procedure protection area. Non-precision procedures are designed for a commencement altitude that should equate to MSA (or the highest relevant sector MSA), but I've known of some procedures that have not completely accounted for it.
Therefore, if the aircraft is starting the descent from a higher altitude, the TAS will be higher. This means that the aircraft might travel further on the outbound leg, in the given time, and then have a larger turn radius in the reversal manoeuvre. All of this could take the aircraft outside the protection area.
The other problem is that the manoeuvre you propose could result in a higher rate of descent than the limits provided in the procedure design. This is because Pans Ops specifies maximum ROD for both Initial and Final segments. Thus, if the pilot must use a higher ROD to reach MDA, there is a greater risk of an excursion below MDA or, at very least, a higher cockpit workload than normal.
All my procedures are protected for the very highest sector MSA, so that issue isn't a problem here for leg length and reversal. My procedures also allow a pilot to intercept the outbound leg by no later than the end of the outbound time, but this only recognises that aircraft within the 30 degree sector might not be established on the outbound track when passing over the IAF. The rule for that here, which is enshrined in our CARs, states that the pilot must have established an intercept angle that is allowing the aircraft to close on the outbound track.
As you can see, this is very different from remaining at MSA until within 5 degrees of the outbound track. The problem with this is, of course, that the longer it takes to reach that stage, the less time is available for descent - thus necessitating a very high ROD. It could even mean that there isn't enough time available to reach MDA, thereby potentially wasting more time than would've been used in establishing within the 30 degree sector in the first place.
I don't think that any State would even contemplate allowing it in any circumstance other than the one I described above. And, of course, other States might not even allow that little bit of flexibility that we allow. The reason why we allow it is because we can be sure that the aircraft will always be contained within the procedure's protection area and have the full time available for descent on the outbound leg.
So... the full application of Pans Ops criteria will allow the things that we're allowing. We apply Pans Ops fully but maybe other States have implemented it slightly differently and, thereby, are not in a position to allow it in their own legislation. The thing that needs to be remembered, as I've said on other topics, is that Pans Ops has no legal standing of its own - the necessary legal coverage is provided by the way each State describes its own implementation of it in its regulations and AIP.
There MIGHT be a problem with the size of the procedure protection area. Non-precision procedures are designed for a commencement altitude that should equate to MSA (or the highest relevant sector MSA), but I've known of some procedures that have not completely accounted for it.
Therefore, if the aircraft is starting the descent from a higher altitude, the TAS will be higher. This means that the aircraft might travel further on the outbound leg, in the given time, and then have a larger turn radius in the reversal manoeuvre. All of this could take the aircraft outside the protection area.
The other problem is that the manoeuvre you propose could result in a higher rate of descent than the limits provided in the procedure design. This is because Pans Ops specifies maximum ROD for both Initial and Final segments. Thus, if the pilot must use a higher ROD to reach MDA, there is a greater risk of an excursion below MDA or, at very least, a higher cockpit workload than normal.
All my procedures are protected for the very highest sector MSA, so that issue isn't a problem here for leg length and reversal. My procedures also allow a pilot to intercept the outbound leg by no later than the end of the outbound time, but this only recognises that aircraft within the 30 degree sector might not be established on the outbound track when passing over the IAF. The rule for that here, which is enshrined in our CARs, states that the pilot must have established an intercept angle that is allowing the aircraft to close on the outbound track.
As you can see, this is very different from remaining at MSA until within 5 degrees of the outbound track. The problem with this is, of course, that the longer it takes to reach that stage, the less time is available for descent - thus necessitating a very high ROD. It could even mean that there isn't enough time available to reach MDA, thereby potentially wasting more time than would've been used in establishing within the 30 degree sector in the first place.
I don't think that any State would even contemplate allowing it in any circumstance other than the one I described above. And, of course, other States might not even allow that little bit of flexibility that we allow. The reason why we allow it is because we can be sure that the aircraft will always be contained within the procedure's protection area and have the full time available for descent on the outbound leg.
So... the full application of Pans Ops criteria will allow the things that we're allowing. We apply Pans Ops fully but maybe other States have implemented it slightly differently and, thereby, are not in a position to allow it in their own legislation. The thing that needs to be remembered, as I've said on other topics, is that Pans Ops has no legal standing of its own - the necessary legal coverage is provided by the way each State describes its own implementation of it in its regulations and AIP.
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This is warming up slowly. Just to correct a previous post, I think, the rules say 15 degrees either side of the O/B trk not 30.
The PANS OPS versus 'state' and even 'local' built procedures also make for an interesting point. Procedure design is NOT standard. The pilots of the 767 that crashed in the Far Eat whilst circling on a procedure that was draw to TERPS standards rather than PANS OPS discovered that the hard way.
We may be getting off my original thread slightly but I think my answer is going to arrive sooner or later.
Thanks for your inputs. Isn't it amazing that this subject is so unclear given that it is our bread and butter?
The PANS OPS versus 'state' and even 'local' built procedures also make for an interesting point. Procedure design is NOT standard. The pilots of the 767 that crashed in the Far Eat whilst circling on a procedure that was draw to TERPS standards rather than PANS OPS discovered that the hard way.
We may be getting off my original thread slightly but I think my answer is going to arrive sooner or later.
Thanks for your inputs. Isn't it amazing that this subject is so unclear given that it is our bread and butter?
Not sure what rules you're referring to but the ones I know specify a track within 30 deg of the initial outbound in order to avoid a sector entry. The arc is further widened to encompass the sector between one side of the 30 deg arc & the final approach course if they're on the same side of the aid eg as used in a
'break away' final
'break away' final
