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Tee Emm
24th Jun 2007, 04:22
A candidate is failed on an instrument rating test in the B737 simulator because he overshot the extended centreline while turning to final. Due to the limitations of field of view on the visual display screen, the runway does not appear until half way around the turn to final.

The testing officer explained that the candidate should have used FMC fixes and waypoints and distance circles on MAP mode to navigate on instruments around the circling approach path with the manoeuvre being flown heads down on instruments rather than by looking outside. In other words to overcome the limitation of the forward view from the simulator, the candidate was expected to use "tricks" in order to position for a stable final approach. In fact,some years ago one airline operator arranged for lights to be placed at various spots on the simulator visual display downwind and base to enable accurate turning points for the conduct of the circling approach.

It doesn't help that low cloud and poor visibility is fed into circling approach exercises in the simulator when already the pilot has his plate full with being unable to visually circle with the airport in sight because of screen viewing limitations. It is often easier to fly a circling approach in the real aircraft than in a simulator. At least you can look over the shoulder to keep the real runway in sight.

It is surely beyond comprehension to allow an examiner to fail a candidate on the visual circling approach manoeuvre when the visual display limitations of a simulator means resorting to gimmicks and tricks with the FMC. In real life a candidate could be rightly criticised for NOT keeping the runway in sight - yet there is no criticism of the heads down on instruments policy in the simulator.

Dream Land
24th Jun 2007, 06:29
I am in total agreement with the points you are making, my question is, whether or not the candidate has been given instruction in the technique described.

Olendirk
24th Jun 2007, 06:56
Well,

some books say, fly it like an instrument approach. And doing that works great. All i need is one short look out in the base to check whether i need to continue my turn or not. Many overshoot the final, because the wind ist mostly blowing from behind. So turning through should be considered. A 1,7 NM circle around the rwy makes a good help.

od

8846
24th Jun 2007, 08:41
Why was a circling approach included in the format of an IRT?

How can you be failed for overshooting a visual intercept?

I was under the impression that as long as you established on an approach track before descent then that was ok?

Did the candidate descend below circling minima?

Even the best simulators that I've been in are pretty unsuitable for visual work. The only thing that you can do in this area is to practice the 'numbers' of a circling approach and when the lights/runway appear in roughly the correct place - well, that's about it really.

I would be really interested to hear more informed comment..

BOAC
24th Jun 2007, 09:09
As presented it sounds unreasonable, but did the pilot fail to correct the turn when visual? I have seen (and flown:eek:) many sim circlings where the last bit has been screwed up when visual. I cannot see how failing to apply an artificial fudge for inadequate equipment could otherwise cause a fail. Was there more to it?

The exercise is even more difficult when circling from 'the other seat' when you sometimes will not see the runway until after the half-way point.

Capn Bloggs
24th Jun 2007, 09:35
I'd dob the instructor in to the CP. What a joke. Sims (every one I've been in)cannot be used like the aircraft to do visual circling without some latitude for sim errors/limitations. It is a VISUAL manoeuvre. Here, the runway threshold MUST be kept in sight at all times, which you can't do in the sim, quite apart from the degraded sim visuals, which are at the best like flying in pouring rain in the dead of night.

Sounds like an FMS nerd if he's requiring use of fixes/magenta lines just to do a base turn. Doesn't work for #$%^ does he? They seem to be hell-bent on using the box...

rubik101
24th Jun 2007, 10:19
A few tips then.

This needs to be well briefed beforehand and you need a pretty sharp PNF to accomplish this!

At the point where you break off the instrument approach and head 45 left or right, PNF selects the landing runway in the APP page, select an extension of 1.5 miles.

Go to LEGS page and select the extension waypoint to the top of the active page. Input a height of 500'. Do NOT execute!

Don't forget to adjust the track and timing downwind for the wind effect!!!

Start timing from abeam the threshold of the landing runway depending on your height.

As you hit the time required, EXECUTE the legs selection and start the turn. Adjust the bank angle selector to get the trend vector on top of the waypoint. Adjust the vertical speed to get the Green Banana over the waypoint.

As soon as you see the runway visually, you will be amazed to see that you are on the centreline and on the PAPI/VASIs.

Take over manually and land!

The trick to SIM or even real circling approaches is to draw a mini Jepp chart and write on it all the points, distances, timings, heights, speeds, Flap and Gear extension points, wind, vertical speeds and so on. Do it on the back of the met, and make it big enough for PNF to read it too. Brief at least 30 minutes before TOD. The only adjustment you need to make on the day is the timing/heading downwind if the wind is very different from that briefed.

Centaurus
24th Jun 2007, 10:42
The trick to SIM or even real circling approaches is to draw a mini Jepp chart and write on it all the points, distances, timings, heights, speeds, Flap and Gear extension points, wind, vertical speeds and so on

Certainly very impressive information but this bears out the point made by Tee Emm that circling approaches in the simulator as taught by some operators is nothing more than trick flying using instrument navigation to solve a visual problem.

I am not sure that reputable regulatory authorities would permit this. Certainly the Boeing FCTM section on circling approach procedure makes no specific direction in terms of FMC navigation in lieu of visual navigation. In marked contrast the FCTM does publish extensive information on FMC planning for instrument approaches. This suggests Boeing does not encourage heads down MAP reading during a visual circling manoeuvre?

MOB P45
24th Jun 2007, 10:47
rubik101

Neat trickery. Is the vertical deviation indicator on the N.D. showing accurate hi/lo info when flying this method?

If you entered the Circling Altitude in Cruise page then you could get a TOD point as well?

javelin
24th Jun 2007, 10:47
Also bear in mind that unless the FMS has dual GPS update, the FMS position may be drifting as you lose multiple DME inputs to keep NAV accuracy high. We do circling approaches in an LPC/OPC but it is really to highlight the traps you can fall into and it is very much a training exercise.

Our sims have good wrap round visuals, but as the original poster says, you still can't see behind the window like you would on a real visual circuit or circling approach.

Dream Land
24th Jun 2007, 12:29
The gouge (FMS) is taught to all Airbus pilots where I was rated, always mentioned that during the actual ride to look about like you were in a real airplane. I didn't know it was a sin to overshoot the centerline as long as you can correct yourself without exceeding a 30 degree bank.

BSD
24th Jun 2007, 13:44
TRE talking here.

The most frequent problem that one sees as an examiner with circling approaches going to pot is due to not enough evaluation of the wind effect, particularly during the turn to base/final.

Modern FMC, electronic flight display equiiped aircaraft give you a track line and precise groundspeed information.

Always, terrain/circling requirements permitting try to arrange your turn to base and then finals to be INTO WIND. The reduction in groundspeed will prove a huge benefit, making for more time to assess the flight path, turn rate required. ROD etc.

Rubik 101 touched on this in his post.

If you can't make the turn into wind, then being able to anticipate the demands of your base turn/final flap extension/turn rate/ROD selection will help no end.

Make it a part of your briefing, and in briefing make sure PM knows what you are thinking. If it should mean that to position the aeroplane for a base turn into wind, the runway is on PM's side of the cockpit, make sure PM knows you want him to include it in his scan, and advise you how you are doing, passing the threshold etc.

Also, if there is an apprecaible headwind on base leg, it will skew the nose towards the runway, thus helping you as PF to enjoy a view of the runway, final approach etc.

Somebody commented " how can you fail? It is not a test item" There is not enough here to know why the examiner said no-go. There may have been other items not done correctly. It may have been an operators check that was failed, not a licence check. In most companies one expects the operators standards to be higher then the authorities.

Try this one on for size though. If someone flies a non-precision, or a circling approach, and the aeroplane is put in a position from which it is impossible to land SAFELY, the examiner will breathe a sigh of relief if a go-around is flown and reversion to plan B takes place. You do have a plan B of course!

Take a look at Alicante runway 28, the VOR/DME approach. It has an offset of 20 degrees from the runway heading.

You could fly that approach perfectly, break out at minima, and be unable to manouver the aeroplane into position for a landing without seriously destabilising the approach with say a crosswind from the left. A go-around and diversion would be cool, throwing it on the ground in an untidy heap would not. If you don't have the fuel to go-around and proceed with plan B, then perhaps plan A was lousy!

Hope that helps,

BSD.

rubik101
24th Jun 2007, 14:22
Just to amplify a point; The 'tricks' I described earlier I use for BOTH the sim and the real thing. I keep the autopilot/autothrottle engaged until I am assured of correct alignment and decent path. The autopilot gives you much more time to scan outside, to monitor and adjust your progress as you make the approach. Also, with the autolpilot engaged, in the event that you have to carry out a missed approach it is much safer and easier to hit ALT HOLD, ensure the correct Missed Approach ALT is set and comence the Go-around by hitting TOGA. Allow the 'plane to take the strain.
Use all the aids and help you can when carrying out a circling approach. It is almost certainly the most hazardous manoeuvre you will ever carry out and if you don't do them regularly, you need to be very confident of your abilities to do it safely.
Many times you will have to accept a tail wind on the base leg as circling is only permitted to one side of the runway. Then you need to have done your downwind heading/track sums well in advance.
You cannot 'wing' a circling approach and expect to be succesful. If you haven't briefed for it before you make your approach and the wind changes, forcing you into a circling approach, take up the hold and take ten minutes to do the sums and write everything down as I mentioned earlier.
Circling means visual.
Visual doesn't mean manual!!!
Manual is for CAVOK..........well, almost!

Happy and safe landings.

SR71
24th Jun 2007, 14:46
I agree with Centaurus....

Isn't this a ludicrous debate?

Lets assume you were doing a circling manoeuvre in marginal visibility and you lost sight of the runway. In reality are you going to continue the approach on the basis of the FMC trickery you've been taught in the sim?

I'd hope not.

This is no doubt one of the trickiest manoevure's out there, but teaching "IMC/FMC" techniques in the sim to solve a visual problem isn't helping anyone fly the procedure in reality.....is it?

:\

Get your downwind tracking and timing right, compute your radius of turn, fly the required bank angle and ROD and if you screw it up, go somewhere else!

:E

rubik101
25th Jun 2007, 09:27
A candidate is failed on an instrument rating test in the B737 simulator because he overshot the extended centreline while turning to final.

Someone needs to point out to the examiner that the circling approach in the simulator is not part of the IR. It is simply an excersise to demonstrate the pitfalls of such an approach; at least that is what it should be!

fireflybob
25th Jun 2007, 10:39
In reality you never fail a check on one item. It may be that the examiner saw a number of things which failed to come up to the required standard.

When I was taught to be an examiner (by CAFU many moons ago!) I was told that if you had to fail anyone (formally) pick something which cannot be argued with! E.g. going below minima. In the subsequent debrief you can then mention any further items.

At the end of the day it's all a question of is the examiner happy to sign your rating? If he/she is not happy to do same he/she has to find a cast iron reason. Its a while since I did any examining but the formal fail paperwork has to show reason(s) for failure.

Believe it or not examiners do not want to fail candidates for test! Remember their authority does not come from the company but the relevant licensing authority (CAA).

Finally you can complain about the conduct of the test but not the result!

Tee Emm
25th Jun 2007, 14:42
Someone needs to point out to the examiner that the circling approach in the simulator is not part of the IR. It is simply an excersise to demonstrate the pitfalls of such an approach

The circling approach is a mandatory instrument test item in Australia and New Zealand - whether in a light twin or airliner. If however, the instrument rating test is done "in house" as part of an airline's cyclic training using the simulator and the company operational policy is that circling approaches are not to be conducted on line flying, then the circling approach test need not be conducted.

While there is value in practicing a circling approach in a simulator as part of training (rather than as a test), in my view it should be practiced in CAVOK and not with the limiting visibility minima. This is due to the visual display limitations of the simulator design.

Interestingly, there is one simulator training provider in USA who conducts type rating on the A320 where the circling approach is conducted at 300 feet above ground level and where full use of the FMC for plotting turning positions is taught. I would hate to be circling at that altitude in any aeroplane - FMC equipped or purely visual...

In terms of a purely visual day/night visual approach such as joining downwind on a normal 1500 ft circuit in a 737, the technique of "drawing" the circuit with waypoints and whatever for base and final fixes, does seem rather gimmicky, in my opinion. Surely pilots' manipulative handling skills and judgement of a circuit have not been degraded to the point where blind and almost total reliance on automatics is considered so vital to the safe and efficient conduct of a flight? It is common to observe in simulator training the almost indecent haste by pilots to engage the automatic pilot after take off for the most simple of exercises such as a circuit or all-engines ILS.

fireflybob
25th Jun 2007, 16:07
I would hate to be circling at that altitude in any aeroplane - FMC equipped or purely visual...


It's all a question of whether and how you are trained to do it but why not?

With some operators at certain airports a circle to land procedure is the only way of landing in specified weather conditions. If the crew have been appropriately trained there is no reason why such a manoeuvre cannot be conducted safely.

In terms of a purely visual day/night visual approach such as joining downwind on a normal 1500 ft circuit in a 737, the technique of "drawing" the circuit with waypoints and whatever for base and final fixes, does seem rather gimmicky, in my opinion.

Tee Emm, I agree with you! There seems to be a growing reluctance to fly a visual approach even when the conditions are ideal to do same. Ok there are issues such as identification of the correct runway/airport but surely pilots such be capable of comfortably hand flying a visual approach?

JW411
25th Jun 2007, 16:40
I will now put my TRE hat on and get prepared to be shot down by all and sundry.

It is not possible to fail a candidate on an "IRT" for screwing up a visual manoeuvre.

The circling approach is no longer a Mandatory Item on the JAA ATPL/Type Rating Skill Test and Proficiency Check Form.

However, as someone else has already pointed out, I would expect a trained crew to be able to make such a manoeuvre. If they could not then it could become an OPC issue.

Now I am a very practical aviator and I get a bit worried about some of our profession who cannot fly such manoeuvres without the use of an FMC. I have no objection to using everything available but I do get nervous when I fly with some youngsters who are pushing buttons when looking out of the window would be a far better idea and also give an instant solution!

So let us get down to basics. The opening gambit on this thread was looking for tips on how to conduct this exercise successfully in a simulator. Here are my little tips.

Before you start, make sure that you give a good brief and do not allow yourself to be rushed into the exercise. In particular, it is essential that you brief the go-around procedures depending on at what point visual contact is lost. For example, if contact is lost downwind then a go-around is initiated and a turn towards the runway is made in order to intercept the missed approach procedure for the instrument let down that got you there in the first place.

The most awkward can be losing sight of the runway on finals which will involve a circling go-around through up to 180°.

If the automatics are available (and approved) then use them. They will fly the aircraft more accurately than you and will allow you more time to manage the situation.

If your aircraft is not fitted with autothrottle then it is vital that you fly the entire procedure at the same airspeed until you are visual on finals for the landing runway. This is not rocket science. If you fly your 45° for 45 seconds turn at 210 knots and then turn on to finals at 150 knots, it simply will not work out!

Make due allowance for drift when downwind. (I notice that one contributer stated that it is necessary to be able to see the runway threshold at all times. In fact, when you are downwind, you are only required to have the "runway environment" in sight. For example, if you were downwind on 27 at Liverpool at night, you may well not be able to see the runway lights but the ramp lights should be easily visible).

In some simulators the visual system is not good enough for you to be able to see the threshold when abeam. In which case, it is encumbent upon the examiner to give you an accurate abeam point. From that point (and assuming that you are still flying at a good steady IAS) time for the circling minima HEIGHT (not altitude) x 3. (EG: 700 ft agl x 3 = 21 seconds) making due allowance for wind. Do not go for more than 30 seconds.

Then commence a level turn on to finals. This is where it usually goes wrong!
If you are using the automatics in basic modes, then get your heading bug round on to the runway heading ASAP. If you try to do it in progressive demands then every time the aircraft gets close to the heading bug the bank will tend to reduce and you will tend to overshoot the centreline.

Now then, you are absolutely not allowed to leave circling minima until the approach lights or the runway itself are in sight. Therefore, it could be that you have to react very quickly.

Most cock-ups occur at this stage. The candidate is so pleased to see a runway that he/she spends a lot of valuable seconds admiring their wonderful achievement. All the while, they are getting higher and higher!

On my current aircraft, 6 things have to be accomplished very quickly:
1. Disconnect the AP.
2. Reduce power (a large reduction).
3. Start descending - even if you see 4 Reds - start descending at 200 fpm or so - you can soon regain the 3° slope later. (If you don't start descending then you will probably pop back up into cloud when you drop land flap and that will mean a go-around).
4. Extend landing flaps.
5. Airbrakes if needed.
6. FDs off.

The circling approach is quite a demanding exercise and it is not often that modern pilots have to fly them. When I was a youngster, NDB letdowns were de rigueur and we flew circling approaches a plenty.

Nowadays they are very unusual and therefore require a great deal of respect. There have been some terrible accidents in recent years (such as Guam) that they should be treated with a huge amount of care and practiced at every possible opportunity.

rubik101
25th Jun 2007, 18:51
Tee Emm, I think you are confusing Circling Approaches with visual approaches. The circling minima is quite often around 300' AGL. It is more likely to be around 600-700; but it is very unlikely to be 1500. Getting PNF to use the FMC and monitor your progress is far safer than both pilots looking outside during this extremely critical manouvre.

JW411, I have no wish to shoot you down....................however;
At the completion of the downwind, timed leg, you will need to commence a gentle (200fpm) decent as soon as you turn the heading bug onto the runway heading. Also, at the same point you will need land flap deployed, Approach speed nailed and the Landing Checks completed as you commence the turn.
Airbrakes or speedbrakes should never be extended with the Flaps extended beyond 10/15 degrees on Boeing or 2 on Airbus.
Gear Down and Intermediate flap must be lowered at the normal point prior to the approach on the Non landing runway. The whole procedure needs to be flown at 150 kts or so until the point where you begin timing abeam the runway.
You can decend below the circling minima as long as you can see the runway. You don't have to be lined up on the centreline before you decend. If you maintain Altitude until you are lined up you will never get down onto the runway.
Otherwise, agreed with the rest!As you rightly point out, preparation is all.
Detailed and thourough preparation is the key to doing this right. Rush the briefing and you will cock it up, no question.

JW411
25th Jun 2007, 19:06
Yes dear boy, I totally agree with you but, in most simulators, you will not always be able to see the landing runway because of the limitations of the visual system, until you are within about 30° of the runway heading.

I say again, and I doubt that you will disagree with me, you must NOT leave circling minima until you have the lights in sight.

We are not talking about the real world of flying real aeroplanes. The question was "how can I do it in a simulator".

(Puts even more armour on).

SR71
25th Jun 2007, 23:28
Whereupon I refer the honourable gentlemen to my previous point...

Isn't this ludicrous?

I shouldn't have to be learning how to do a visual manoeuvre in the sim...especially if the techniques differ!

That is a categoric recipe for disaster.

BTW, I thought JAA minima (MDH) for a Circling Approach was 600ft/2400m?

The Boeing 737 FCTM has instructions on how to fly a Circling Manoeuvre.

All the techniques suggested for using the FMC in the fashion suggested, assume the ANP is pretty much zero - a problem conveniently forgotten about in the sim.

In a radio updating environment, one would hope that ANP is significantly less than RNP and certain FMC updates will alert you to the fact that it isn't, but even being 0.3nm displaced from where you really are is going to make your life difficult on this hybrid RNAV Circling Manoeuvre!

Look out the window.

:ok:

Waghi Warrior
27th Jun 2007, 02:28
The circling approach in the sim can be very tricky as the visuals can easily screw you up,it's happened to me more than once. Where as doing a circling approach in the real aircraft in my opinion is a lot easier.

212man
27th Jun 2007, 08:26
JW411, I'm puzzled by what the Guam 747 accident got to do with circling approaches: it was an ILS flown with no glideslope.

A37575
27th Jun 2007, 15:56
At the completion of the downwind, timed leg, you will need to commence a gentle (200fpm) decent as soon as you turn the heading bug onto the runway heading

At night this is potentially dangerous. Unless you are 100% certain of the geographical position of the critical obstruction that dictates the published circling MDA, you should not be descending below the circling MDA until aligned with the landing runway. Commencing any descent below the published circling MDA (slow or otherwise) on downwind or base leg immediately places full responsibility for obstacle clearance upon the captain. It becomes then a case of a "courageous decision" in the manner of Sir Humphrey of Yes Minister.

JW411
27th Jun 2007, 16:25
212man:

Quite right; I have the wrong accident but the right company I think?

Zeffy
27th Jun 2007, 16:39
Are you thinking of the Air China B767 at Busan?

http://aviation-safety.net/database/record.php?id=20020415-0

http://www.flightsafety.org/ap/ap_dec05.pdf

Circled and crashed at the (TERPS) Cat C MDA.

Reel Marine
28th Jun 2007, 01:03
The circling approaches that are done in the sim are done because that is the way that the Sim is certified for, not the way you will actually fly the circling approach in real life. You have to maintain visual contact with the runway during a circling approach so when doing a real one in the sim you will loose the visual so hence the screwed up way to do it.

In the US most sims are certified to do the straight in approach to runway 4r at KJFK then circle to land 31R. When you have a good sim with daytime visual there is no need for FMS work as you can see every detail including the hotel and layover bar so keeping contact with the runway is no problem as you VISUALLY fly the approach.

In a real circling approach in the airplane you do it according to your manual and time the legs accordingly, this should be taught once in the sim, usually on day 1 on how to do it properly.

Having said all that, your sim instructor should have tips and gouges on how to fly the checkride circling approach so you dont screw it up. Turning wide on final is NOT a bust over here unless your unstablized by 1000 IMC or 500 VMC and still try and salvage it.

If you do screw it up then all youll get is a circling restriction on your license or we can stop the exam during the ride and train you properly on how to do it and continue the ride and repeat it and if it is successfull then you are golden

Also keep in mind that most airlines have a restriction in their OPSPECS to not commence a circling approach unless it is 1000 and 3, far above the minimums for circling.

Hope this helps

Zeffy
28th Jun 2007, 01:25
Also keep in mind that most airlines have a restriction in their OPSPECS to not commence a circling approach unless it is 1000 and 3, far above the minimums for circling.

While I fully agree that the training to circle in simulators is solely useful for... well, circling simulators ----- the notion that joining the FAA's "1000-3 club" will make circle to land maneuvers just as safe as a flying VFR traffic pattern is simply rubbish. :*

Circling MDA's provide no more than 300' of Required Obstacle Clearance.

Maneuvering beneath a 1000' ceiling may --- or very well may not ---provide additional margin above the dirt/trees/rocks/obstructions.

Please -- high HAA's do NOT imply additional ROC. :=

IMO, the concept upon which the referenced OpSpec has been predicated is fundamentally flawed.

Reel Marine
28th Jun 2007, 01:40
I agree with what you say, perhaps I mispoke and implied that the circling begin at 1000'.

This is just a VISIBILITY requirement but operators must adhere to the proper minimums for safe obstruction clearance, hence the need to go to minimums and circle for proper distance to the airport

Thanks

A37575
28th Jun 2007, 14:07
how to fly the checkride circling approach so you dont screw it up. Turning wide on final is NOT a bust over here unless your unstablized by 1000 IMC or 500 VMC and still try and salvage it.

If during the conduct of a circling approach you enter IMC, then whether or not you are stabilised by 1000 ft does not mean a thing - because by then in IMC you should have already commenced the GA into the missed approach procedure.:ok:

BOAC
28th Jun 2007, 14:43
As a 'by-the'by', triggered by the words "Turning wide on final", how do folk in TERPS land stay within 1.7nm of the runway? It is virtually impossible to do this even in a 737, and as we know, the 2002 Busan fatal (767) was at 2.2nm from the threshold.

Zeffy
29th Jun 2007, 16:06
how do folk in TERPS land stay within 1.7nm of the runway?

As you probably know, that particular issue has a rather long history (http://www.faa.gov/about/office_org/headquarters_offices/avs/offices/afs/afs400/afs420/acfipg/open/media/Hist%2092-02-105.pdf).

gonso
30th Jun 2007, 02:22
What happened to : "Extensive use of the FMC (heads down) should be avoided bellow 10.000ft" ? Our books mention this a couple of times.

My trick (ever since I started using this, my life became sooo much easier), is the following and it is for all types of Boeing (prob Airbus too).

A/p engaged. When time's up on downwind, I turn the hdg sel knob ALL THE WAY to rwy QDM, corrected fro wind (no more than 10 deg usually).
Then I look on my map or ND and am looking at the white turn vector. (it looks better if your range is set at 20NM, because you see two lines instead of one). If the trend shows that I will undershoot, I change the bank angle selector to a smaller value (ie. 15deg). I continue fiddling with the bank angle selector until the projection shows that I will be right on the centerline.

If the at the start it shows that I will overshoot, in some types you can change from 25 to 30 degrees. If not, well, thats the best you can do. At least you know beforehand.

It needs to be practiced a couple of times before the first ever go. After that, it becomes 2nd nature.

I have never been criticised for using this technique by a TRE for the past 12 sim rides at least. They are so impressed form the outcome that there is little they can say :ok:

Tee Emm
1st Jul 2007, 14:21
I continue fiddling with the bank angle selector until the projection shows that I will be right on the centerline.



Fiddling with the Bank Angle Selector? Now that is what I call a real gimmicky thing to do. Despite extensive perusual of the various Boeing manuals I was unable to find any reference to this technique...

AirRabbit
1st Jul 2007, 16:54
Once again, my good friend, Centaurus, has “nailed” the answer to what some believe is a difficult issue to understand. A circling approach is a visual conclusion to an instrument approach procedure. It is predicated on the pilot being able to visually acquire and identify the airport, and keep at least some of that identified airport in sight throughout the maneuver. This does not include a “heads down” FMC, or similar, procedure. There is no airplane manufacturer, at least of whom I am aware, that advocates “heads down MAP reading” while engaged in any visual maneuvering – circling approach or other. In fact, in the US, here is the regulatory requirement that speaks to this particular issue:
FAR Section 91.175(e)(2) Missed approach procedures.
“Each pilot operating an aircraft, except a military aircraft of the United States, shall immediately execute an appropriate missed approach procedure … Whenever an identifiable part of the airport is not distinctly visible to the pilot during a circling maneuver at or above MDA, unless the inability to see an identifiable part of the airport results only from a normal bank of the aircraft during the circling approach.”
In case anyone may wonder what is considered “an identifiable part of the airport,” that includes the runway, other runways, taxiways, lighting systems, ramps, buildings, including the terminal, etc. Basically it includes structures on the AIRPORT. It does not include the expressway overpass or the fast food restaurant just the north of the final approach. Those are NOT part of the Airport. Also, it would be just as phony to “build” additional reference points into a simulator’s visual scene that are not present in the real world.

Additionally, regarding some of the comments about when to begin a descent from MDA when conducting a circling approach – again, admittedly, from the US point of reference – here is the regulatory requirement that speaks to this specific issue.
FAR 91.175(c)(1) Operation below DH or MDA.
“Except as provided in paragraph (l) of this section, where a DH or MDA is applicable, no pilot may operate an aircraft, except a military aircraft of the United States, at any airport below the authorized MDA or continue an approach below the authorized DH unless … (1) The aircraft is continuously in a position from which a descent to a landing on the intended runway can be made at a normal rate of descent using normal maneuvers, and for operations conducted under part 121 or part 135 unless that descent rate will allow touchdown to occur within the touchdown zone of the runway of intended landing;”
Centaurus is absolutely correct in that some operators have fallen into the trap of using the simulator to teach “trick flying using instrument navigation to solve a visual problem” in an effort to simply “fill the square” of having to meet a circling approach requirement. This should be easily recognized by the fact that in almost all of those “trick” solutions, the pilot flying must necessarily lose sight of not just the landing runway, but lose sight of the entire airport – and in some cases for a reasonably extended period of time. In the real world this may very well lead to disastrous consequences. There should be no operator, anywhere, who should allow, let alone teach, such practices – and no regulatory authority would approve such a practice.

gonso
1st Jul 2007, 17:12
Tee Emm, you will have to fiddle with something on the MCP anyway, since we all agree that the use of the autopilot is very helpfull while you are
looking out.

Instead of fiddling with the HDG SEL to achieve wings level-correct track and on the extended centerlline, you can use the bank angle selector to "tighten" or "open" your tradjectory. Trust me, after two or three adjustments, you will not have to touch it again beyond half way through the turn.

Obviously, Boeing makes no mention about this procedure in the manuals. It has no guidance for the use of the MCP for this maneuver...period. Bank angle selector is there, so it can be used. It is just another roll control feature. There is no limitation about it.

We are just using it for the bank angle 15 on one engine, and we think that this is all it is meant to do. If that was true, it would have only selection "15" and "AUTO". It does not though.

By all means, I am not saying that this is the God sent method of flying circling aproaches and everything else is wrong. All am saying is that I have being using this for some years now and it works very well with no long faces from TREs.

It is just food for thought.:ok:

SR71
1st Jul 2007, 17:32
AirRabbit,
I did say as much.
The ICAO reference is in Doc 8168, Section 1, Part 4, Chapter 7.
As for descents below MDA/H, it says:
When the OCA/H is established, an MDA/H is also specified to allow for operational considerations. Descent below
MDA/H should not be made until:
a) visual reference has been established and can be maintained;
b) the pilot has the landing threshold in sight; and
c) the required obstacle clearance can be maintained and the aircraft is in a position to carry out a landing

Dream Land
1st Jul 2007, 19:33
I am not sure that reputable regulatory authorities would permit this. Certainly the Boeing FCTM section on circling approach procedure makes no specific direction in terms of FMC navigation in lieu of visual navigation. In marked contrast the FCTM does publish extensive information on FMC planning for instrument approaches. This suggests Boeing does not encourage heads down MAP reading during a visual circling manoeuvre? So then what would you propose, the CATD sim is useless in actually simulating a real visual approach, regulatory authorities have permitted and will continue to permit this since there is no alternative at this point in time. :hmm:

AirRabbit
1st Jul 2007, 20:46
Hi Dream Land:

What you suggest happens is not entirely true.

The regulatory authority in the US (the FAA) does not authorize circling approaches in a simulator that has not been evaluated to be able to do so WHILE complying with the regulatory requirement I quoted above (...must maintain an identifiable portion of the airport in sight throughout the maneuver); AND the maneuver demonstrated must be flown where there is at least a 90 degree difference from the approach to the landing runway - (i.e., Memphis Tennessee approach to Rnwy 27 circle to land on Rnwy 18R) - there are several such runway combinations at US airports. Once successfully evaluated, the simulator may then be approved for circling approaches; but not until then.

BOAC
1st Jul 2007, 21:07
If the circling approach HAS to be included in a sim detail, it could be so much more 'do-able' if it allowed the circle on the 'easy' side. My last 'circling' in the LHS required a right-hand circuit due to the approach/vis and landing runway selected. Out of interest no FMC was harmed in the production of the manoeuvre but there had to be a portion where the runway lights were effectively out of sight to both, and since they were the only 'visual' clues on a 'generic' airfield, rendered it technically incorrect. Should we be reviewing the way we 'fudge' the requirement to get the all-important 'tick in the box'?

AirRabbit
2nd Jul 2007, 00:01
Hi BOAC:

I think you raise a good question; "Should we be reviewing the way we 'fudge' the requirement to get the all-important 'tick in the box'?"

And the way I'd answer would be to ask 1) what is it the pilot will be expected to do on a cold, dark, and stormy night; 2) when something goes dreadfully wrong, who is it who is going to pay the ulitmate price, and 3) who is going to have to "pay-the-cheque" when the law suits start appearing? - and you know they will...

Bally Heck
2nd Jul 2007, 00:31
Fascinating thread. Perhaps two systems at work here? The US system seems to allow lower circling minima and much tighter circuits (TERPS?) Must you be visual with the airfield at all times?
The JAA circling approach allows you to lose visual contact with the field as long as you stay within the circling area and above circlng minima for the sector you are in until you become visual. 5.28 nm for Cat D aircraft. FMC used for wind assessment mostly. How do you stay visual in a jet, downwind 3 or 4 miles from an airfield?

AirRabbit
2nd Jul 2007, 14:38
Hi Bally Heck:

You too, ask a good question, "How do you stay visual in a jet, downwind 3 or 4 miles from an airfield?"

The answer is, I suppose, that according to the US rules, a normally recognized traffic pattern is not expected to be flown - so a "crosswind," "downwind," or "base" leg are not part of a circling approach.

As far as the US rules allowing a "lower circling minima" is concerned, I guess that would depend on "lower" than what; lower than VFR conditions, most of the times, yes; but circling minima are normally higher (in some cases significantly higher) than the associated straight-in instrument minima. Many US operators have decided, on their own, to limit circling approaches for their operation to minima equal to VFR minimums (1000 feet and 3 miles).
However, even at VFR minima, I have always wondered about the sanity of anyone wanting to deliberately take a jet (particularly the types of jets that are in air transportation service today) and wander around down amongst the "weeds!"

And ... with respect to the JAA requirements for circling approaches ... how is one to determine they ARE remaining within the circling approach area if they no longer have visual contact with the airport?

Zeffy
2nd Jul 2007, 17:09
Many US operators have decided, on their own, to limit circling approaches for their operation to minima equal to VFR minimums (1000 feet and 3 miles).


That's what I was ranting about earlier -- i.e., the FAA's "1000-3 club".

"Equal to VFR minimums" does not imply 1000 feet of ROC.

TERPS provides 300' above the controlling obstacle and very little maneuvering room.

http://i202.photobucket.com/albums/aa92/zeffy_bucket/CTL.gif

No crew should ever infer that circling at 1000 AFE is a walk in the park.

Note that the Cat D circling MDA at KORH (http://www.naco.faa.gov/d-tpp/0707/00652IL11.PDF) is almost exactly 1000 feet above the airport.

How many pilots fully grasp that the circling maneuver at KORH in the "comfort" of 1000-3 weather will include trolling for obstacles a scant 300 feet below?

AirRabbit
2nd Jul 2007, 20:45
Hi Zeffy

That's what I was ranting about earlier -- i.e., the FAA's "1000-3 club".
"Equal to VFR minimums" does not imply 1000 feet of ROC.
TERPS provides 300' above the controlling obstacle and very little maneuvering room.
No crew should ever infer that circling at 1000 AFE is a walk in the park.
Note that the Cat D circling MDA at KORH is almost exactly 1000 feet above the airport.
How many pilots fully grasp that the circling maneuver at KORH in the "comfort" of 1000-3 weather will include trolling for obstacles a scant 300 feet below?
Hence, my comment ... "even at VFR minima, I have always wondered about the sanity of anyone wanting to deliberately take a jet (particularly the types of jets that are in air transportation service today) and wander around down amongst the "weeds!"

SR71
2nd Jul 2007, 22:57
The JAA circling approach allows you to lose visual contact with the field as long as you stay within the circling area and above circlng minima for the sector you are in until you become visual.
Curiously, where does it say that?
PAN OPS Doc 8168,
7.2.2 After initial visual contact, the basic assumption is that the runway environment should be kept in sight while at minimum descent altitudeheight (MDA/H) for circling. The runway enviroiunent includes features such as the runway threshold or approach lighting aids or other markings identifiable with the runway.
and
7.4.1 If visual reference is lost while circling to land from an instrument approach, the missed approach specified
for that particular procedure must be followed. The pilot will make an initial climbing turn toward the landing runway
and overhead the aerodronie. At this point, the pilot will establish the aircraft climbing on the missed approach hack.
I'm not quite sure of the relationship between JAR-OPS and the above document....