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Visual Approaches, Non-Precision


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Is one required to cross the FAF at the FAF altitude on the approach plate when one is given a "Visual Approach" IFR clearance?

To be clear, one has not cancelled IFR, one has just been given "the visual to..." I know "cleared a visual" is an IFR clearance.

Still, once cleared the visual, is one free to determine one's altitudes or must one stay with the published altitude for the FAF, (and of course the procedure turn & sector altitudes, etc)?

Can one turn inside the FAF on a visual if noise abatement is not required?

Or are these more to do with stabilized approaches - meaning, one should fly to the FAF altitude and then begin the visual from that point because anything lower is a non-stabilized approach.

I believe I know the answers to these questions - crossing the FAF altitude is required on a Visual Approach - but I'll be darned if I can find a reference in the CARS, (the search feature is terrible - thousands of irrelevant links).

Thoughts?

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Disagree, Don. Crossing altitudes are minimum altitudes. On an IFR approach, an SCDA technique will probably cross the FAF and preceding IAF(s) at altitudes higher than those minima published. Noise abatement notwithstanding. But that is not your question.

To look at your visual approach example, look at it from the other side of your suggestion that one is required to cross the FAF at the published altitude - is that what you mean? - because many visual approaches are executed inside the FAF which is typically 3-5 miles from the threshold. Is it reasonable to expect a Navajo to turn a 5 mile final while on a downwind leg of an IFR flight plan cleared visual approach? Or how about the wide-body that accepts a visual from 10 miles out and conducts an SCDA or even an ILS in visual conditions because some might argue it is still safer especially if PAPI are not available? An excerpt from ATC's MANOPS would help clarify what exactly is needed for issuance of a visual approach clearance. Perhaps one of our ATC-ers can help in that regard. I don't think I've ever seen any reference, other than company issued procedures, regarding visual approach pilot procedures such as you've asked other than to have the runway of landing in view at all times..

FWIW :)

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I don't believe there is any restriction on FAF crossing altitude. Some places in the USA where there are numerous airports in close vicinity use a minimum FAF crossing altitude to maintain separation and some places use it for noise abatement but other than those two scenarios (and good judgement) I can't remember any restriction.

On the subject of turning inside the FAF - definitely no restriction on doing this.

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other than to have the runway of landing in view at all times..(perhaps that is an airline specific SOP?)

I do not believe you have to have the runway of landing in sight at all times, you can just have the airport in sight and if following another aircraft, you must call the aircraft in sight.

Unless ATC adds any restrictions, you may fly the approach as if you were doing a VFR approach, no restrictions to FAF altitudes etc....at least that was always my take and I never had anyone question it. :biggrin1:

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Don,

A visual approach is defined in CARS (from memory) as an approach where the pilot proceeds visually toward the runway he will be landing on once he has that runway in sight and/or the traffic he will follow. Therefore, once you're on a visual approach, unless there is a published visual approach procedure, there are no restrictions other than what we as ATC might have given you. We routinely add such restrictions to accomodate Tower traffic and to reduce internal coordination. As a result, at most airports I've worked at, it is common for you to be given an "intercept final outside the FAF at 3000 or above". We will then use the FAF of the approach that's on the ATIS as it is the one we expect you to have briefed and set up.

The restrictions that do exist are for noise abatement. These are usually that you'll establish yourself on final prior to the final approach fix at the last altitude assigned by ATC and thereon in never lower than the GS. However, those are not part of CARS or of any ATC rules. I personnally, however, never assume you would know about those and issue the proper restrictions or set you up so it will not be an issue.

At other airports, CYQB for example, we commonly issue a "no restrictions" visual approach. Yet, we usually specify that there are no restrictions so as to remove any ambiguity.

Hope this helps!

Felix

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..(perhaps that is an airline specific SOP?)

I do not believe you have to have the runway of landing in sight at all times, you can just have the airport in sight and if following another aircraft, you must call the aircraft in sight.

On reflection of past behaviours Kip, I'll give you that. A lot of visual approaches are defined in company operating procedures. Some companies will not allow visual circling procedures unless 1) trained for the procedure in the sim and 2) conditions of VMC or better.

Because of the nature of my particular operation, we are sanctioned and trained for IFR circling at or above minimums.

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Don, AIM RAC 9.6.2 might be what you're looking for. That section lists what the pilot-in-command requirements are. Absent is any discussion of charted minimum altitudes. Present, however, as discussed on this thread, are the requirements to maintain noise abatement criteria.

The AIM is pretty clear that a visual approach is not an instrument approach procedure and there is no associated missed approach procedure. To me, that strongly suggests that none of the restrictions of a charted instrument approach, including FAF crossing height (which might well vary among various approach procedures to the same runway), apply. Noise abatement procedures are not IFR requirements per se, so that seems to line up.

I hope this helps, and that all is well with you and yours.

Cheers

Vs

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Hi Moon;

Re, "Disagree, Don. Crossing altitudes are minimum altitudes. On an IFR approach, an SCDA technique will probably cross the FAF and preceding IAF(s) at altitudes higher than those minima published."

Thanks, that helps. I didn't write the question as well as I could have and actually didn't take the SCDA into account because that had already (in my mind!) answered my question. I was thinking of minimum crossing altitudes rather than a "must-cross, not high, not low" concept and I didn't make that very clear when I asked the question!

What I was actually driving at and got too fancy with was, When on a Visual Approach (which is an IFR clearance), must one remain at or above the FAF crossing altitude, or may one descend below the FAF crossing altitude outside the FAF? That's the way I should have asked my question!

Seeker, re,

"On the subject of turning inside the FAF - definitely no restriction on doing this."

Possibly - other than published noise abatement procedures, (Moon's example of a Navajoe), and airline-published procedures.

Kip, re

"I do not believe you have to have the runway of landing in sight at all times, you can just have the airport in sight and if following another aircraft, you must call the aircraft in sight.

Unless ATC adds any restrictions, you may fly the approach as if you were doing a VFR approach, no restrictions to FAF altitudes etc"

On having the actual runway in sight, yes, I think that's correct. I'm not that certain that a visual approach is the same as a VFR approach because one is still "IFR" and as such I am wondering about required altitudes, specifically the FAF crossing altitude and as mentioned above there was a better way to ask the question!

SA,O, re,

Therefore, once you're on a visual approach, unless there is a published visual approach procedure, there are no restrictions other than what we as ATC might have given you.

. . .

Hope this helps!

It does indeed help Felix, thank you. As I work through these responses I've done some thinking about this and may be confusing airline procedures, particularly the requirements of the stabilized approach, and notions behind "good airmanship" with legal requirements to remain at/above a certain defined altitude.

Vsplat, re

"The AIM is pretty clear that a visual approach is not an instrument approach procedure and there is no associated missed approach procedure. To me, that strongly suggests that none of the restrictions of a charted instrument approach, including FAF crossing height (which might well vary among various approach procedures to the same runway), apply. Noise abatement procedures are not IFR requirements per se, so that seems to line up.

I hope this helps, and that all is well with you and yours."

It does help, and I believe reinforces what Felix has offered above - that there isn't a legal FAF crossing altitude requirement but that ATC sometimes provides other guidance for the Visual and that, of course, is to be adhered to.

The problem I'm wrestling with is, is it acceptable and / or legal on a visual approach to cross the FAF below the FAF-crossing altitude. I am hearing that it is both legal and, notwithstanding specifically-issued ATC clearances, acceptable to cross the FAF below the FAF altitude, and that any restrictions are airline-specific in terms of stabilized approach policies, etc. BTW, everyone's well and thriving, thanks - our daughter has a little one one the way, due in September.

Thanks, all. The context of the question was, I was focussing on the causes of CFIT approach accidents and the need to remain stabilized on the approach, and the question of what was legally-required when on a Visual Approach in terms of FAF crossing altitudes. I have altered my perception and thinking on this and I thank everyone for helping that process! The stabilized approach remains a primary principle I think, in terms of avoiding the CFIT risk but that process belongs in the cockpit, and with the individual airline, as it probably should.

Don

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Good to get into this kind of topic again, Don. Always a stimulating question from your corner! I expect the CAR's are silent on something like this as there is just too much common sense involved. For large aircraft, especially jet aircraft, it is well established, at least by western carriers, that a stabilized approach is the best. From my experience, it is quite easy to develop a perfectly stabilized approach while doing the visual manoeuvring. Given the average minimum altitudes at the FAF, assuming the final approach manoeuvre commences outside, in all likelihood, the stabilized approach will be above this minimum altitude.

There is always the possibility of a go-around for any IFR cleared visual approach. Easy-peasey - "...Going Around. Maintaining VFR."

Why would anyone ask to do a visual approach in marginal VFR? Now that's go good question too. As far as I remember, ATC will allow contact approaches into uncontrolled aerodromes. Hence the importance of good local (MF) communications as well. I also recall that a miss off a contact reverts to the normal missed approach procedure for the runway cleared.

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Hi Moon;

It's interesting stuff, isn't it?!

I'm thinking back for example to the UPS A300 accident at Birmingham - they weren't visual and weren't cleared a visual and they crossed the FAF altitude, (on a LOC-only appr) about 200ft high, then without visual contact with the runway at 1200' ASL they descended below the MDA, caught sight of the runway and continued to descend at up to 2000fpm on what was essentially a black-hole approach. No mention was made of the VASI, which would have been all-red just after descending below the MDA about 3nm back. They said they had the runway about 5 or 6 seconds before they first hit trees.

I was searching for the ways in which the FAF altitude is "protected" aside from stabilized approach SOPs, airline policy, airmanship and an abundance of caution under such conditions, and trying to assess risk when the aircraft is permitted or intentionally taken below FAF altitudes, (with commensurate low rate of descent, high-power settings, - the opposite of "dive-and-drive", etc).

EDIT to Add: A couple of questions follow as "corollaries":

1) If the FAF isn't a 'hard' altitude and one can descend below it after being given an IFR clearance for a "Visual", can one also descend below the FAF on an ILS (or RNAV) is one isn't cleared a Visual?, and,

2) If the above statement is true, what would be the result of either not descending to, or descending below the FAF / FAWP altitude in the sim on an IFR/PPC renewal?, (I'm not going anywhere with this - I'm just curious how the question is viewed in the context of a ride instead of the context of normal, daily ops). end of edit.

I can see a Navahoe turning inside the FAF on a Visual but interestingly, I'm not sure how a stabilized approach can result from any turn inside the FAF in a Part 705 airplane, at least not from what I've seen anyway.

I wonder if close-in Visuals are asked for to save time and/or fuel? I know the savings aren't there but I wonder if there is a sense that cutting it tight in produces meaningful savings?

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I can see a Navahoe turning inside the FAF on a Visual but interestingly, I'm not sure how a stabilized approach can result from any turn inside the FAF in a Part 705 airplane, at least not from what I've seen anyway.

I wonder if close-in Visuals are asked for to save time and/or fuel? I know the savings aren't there but I wonder if there is a sense that cutting it tight in produces meaningful savings?

Don, in CYQB, the FAF can be as far as 6 or 7 miles back. We'll often see CRJs and DH8 as well as the Embraer jets turn well inside on a visual to 24. In that particular instance, our minimum vectoring altitudes are fairly high because of terrain to the north and therefore an intercept below the GS can only be made at around 12 miles final (more with cold corrected MVAs). Often times, the north of the airport is free of traffic and is therefore open for a downwind descent and tight approach saving quite a bit of time and fuel.

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Hey Don.

To your additional questions:

1) When following IFR and on an IFR approach clearance, separation from obstacles and terrain is built in to the infrastructure, but that infrastructure assumes that the pilot in command will respect all minimum altitudes. Minimum FAF crossing altitude is as binding as MDA/DH. [As an aside, that is why there is no corresponding 'warm' correction for altitudes associated with an approach. While cold temperature corrections raise the indicated altitude above the charted value, 'warm' corrections would have the effect of lowering the indicated altitude below what is charted, and that is prohibited. ]

2) When accepting a visual approach, a pilot-in-command assumes direct responsibility for obstacle, terrain and, in many cases, traffic separation. That's why the FAF is no longer binding. Probably still a good idea, but not binding.

We can talk at length about the correlation between visual clearances and unstable approaches, but I can think of far more pleasant places to have that discussion...I'll be sure to add that to my list of reasons to drag you into town next time I'm on your coast.

All the best

Vs

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I should think that being close to a 3 degree glideslope, even on a visual, if that 3 degrees coincides with a published FAF crossing altitude, would keep you in the comfort zone in the landing configuration with regard to common power settings, etc, or whatever in your mind makes it easier to go around with an engine out.

It's likely a very good idea to avoid at all costs a situation where you have to suddenly get well into the power on the good engine when you have gotten yourself into a low altitude box where you can no longer trade altitude for velocity. Failing all that calculation stuff, in a big heavy transport category airframe it's always a good idea to stay as far away from the ground as possible until you've landed.

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Don, in CYQB, the FAF can be as far as 6 or 7 miles back. We'll often see CRJs and DH8 as well as the Embraer jets turn well inside on a visual to 24. In that particular instance, our minimum vectoring altitudes are fairly high because of terrain to the north and therefore an intercept below the GS can only be made at around 12 miles final (more with cold corrected MVAs). Often times, the north of the airport is free of traffic and is therefore open for a downwind descent and tight approach saving quite a bit of time and fuel.

Felix... Don't ask any of us Jazz drivers what we think of operations at YQB ;)

For an airport of it's size and traffic volume, it's hands down one of the more frustrating airports we operate into, specifically during VMC. I would have to argue about saving time and fuel. We even have been issued memos telling us not to even ask about using different runways. Not saying it's always bad, but I've seen some pretty questionable practices there on occasion.

Don, I see many guys descend to circuit altitude when cleared for the "visual" and start from there (doesn't make much sense to me but alas). There are no limitations regarding FAF crossing altitude (outside specific procedures/noise etc).

In the US however, ATC will issue altitude alerts if you are ever below a minimum IFR altitude, even if you're cleared for a visual. Visuals into Windsor, ON are always fun on 07 because typically you always end up below the minimum IFR altitude, and you get these panicked calls from the YQG tower saying "Detroit approach is on the line and they advise 'Altitude Alert'- you're below the minimum safe IFR altitude....". We have to kinda laugh because how else are we going to land on the runway without flying the instrument approach? But maybe in the US, it's expected that you will cross the FAF at or above the min IFR altitude.

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S A,O

I recall many years ago when the north parallel opened at YVR, the FAFs were placed about 10nm in accordance with some ICAO standard, (like the centerline taxiway lights instead of edge lights). I thought it was not a very good idea as it was too far out in both distance and time to be a realistic check on the descent. It was changed after many complaints.

For a stabilized approach that isn't "heroic", (as anyone can do it and those with 'hands' can make it look pretty), at least a five-mile final is required, sometimes more for Category D airplanes and CATII/III ops.

Re, "...and tight approach saving quite a bit of time and fuel."

That's the impression one gets regarding time and fuel but over the years enough data has been examined to show that very little time and fuel is saved by keeping speeds up or turning in tight. When balanced against the benefits of a stabilized approach, the percentages just aren't there. Here's why:

It depends upon the airplane & engines, but for the CFM56 the fuel usage for the approach phase, (usually first flap selection to t/d), fuel usage is about 16kg per engine per minute during this phase. The approach phase (where the airplane is dirty), normally lasts around 5 minutes for narrow-aisle twins like the B737 and A320 types, perhaps a bit more. The average (statistical mean) is about 85kg of fuel for this phase for this type of engine.

From the FAF to t/d is usually about 2 minutes, maybe a bit more depending upon distances FAF-to-Rwy, flap selection, headwinds, temperatures and so on. A normal, stabilized approach from the FAF uses about 60kg of fuel and takes a bit over two minutes. Inside the FAF the engines have to be sufficiently spooled above idle for response time, the rate of descent less than 1000fpm unless briefed, the speed within 10kts of Vref+5 or Vapp, corrected for wind as applicable and the airplane tracking to the runway. Bear in mind, this is Part 705 aircraft I'm talking about. Fuel usage is lower during the initial approach phase because the path to the FAF is usually flown at idle or close to idle thrust while flap is selected during the deceleration. Fuel usage is higher at/after the FAF due to flap, gear and drag due slightly higher AoA. For decades, reduced flap settings have been ways of saving fuel during this phase but the penalty is higher approach speeds, more wear and tear on the brakes and reversers rather than the flap tracks.

When all is going exactly as planned and as one would fly a normal approach, the maximum one could save would be around two minutes possibly three, and a maximum of about 30kg of fuel providing the airplane was equally fine-tuned after the FAF.

When one considers the data and the operational realities, there is very little benefit to tight turns at/inside the marker. I know it can be done and be made "pretty" to boot, even with heavier wide-bodies but both the TSB and the NTSB have put the stabilized approach at the top of their list as preventative actions crews can take. Hope all this is helpful !....didn't want to put everyone to sleep...

Vsplat again very helpful thanks. On finding venues, yessir, I'm in! :b:

feather, re your remarks, :tu:

Canoehead, yeah, I can recall one of those calls, even here! Interestingly, there was no such call to the UPS A300 at Birmingham however.

Regarding saving fuel, bear in mind of course that I'm only talking about managing the airplane without other traffic slowing one down. The numbers I mention aren't academic, but they are good when one has sky. The opportunities for fuel saving are out the window and a turn in tight when offered, (at SFO...BTDT...), is a strategic manouevre not primarily a fuel/time saving one and is often a better alternative if there are lots on final. And in places like LaGuardia, one isn't doing a thing or asking a thing except to keep the guy in front in sight and get off the runway as quickly as possible...

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Canoehead,

I understand your issue with CYQB. This is a discussion we should be having around a BBQ, however, as it would become too tedious in the written format. In short, our restrictions and procedures don't permit us to do as much as we would otherwise love (and used) to do. :o

Don,

Very interesting points re: fuel usage. I'll pass it on to the folks. Thank you!

Felix

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