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Straight-in versus Visual Approach (IFR Flight Plan)

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Straight-in versus Visual Approach (IFR Flight Plan)

Old 8th Apr 2010, 11:03
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Straight-in versus Visual Approach (IFR Flight Plan)

You are operating your Cat. C/D aircraft under an IFR flight plan and making your approach under "positive radar control/Terminal Airspace" with Radar Vectors or having been Cleared the IFR Procedure.
You request to ATC below.
What is the legal and operational difference between requesting/ATC giving you the Clearance to perform a;

STRAIGHT IN APPROACH
or
VISUAL APPROACH

and the various legal implications - if any?
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Old 8th Apr 2010, 11:22
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Never did hear about being cleared[ for a "straight in approach" on it's own merit. Depending on the layout of aids and runways etc I would assume it would mean I was cleared for some sort of instrument approach without a reversal procedure?

A visual approach would clear you to maneuver the airplane as you require.
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Old 8th Apr 2010, 11:51
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You're not comparing like for like.

"Straight in" describes one option for how you arrive at the start of the final approach.

"Visual" describes one option for the navaids in use (or lack of in this case)
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Old 8th Apr 2010, 12:57
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Straight-in (ILS or VOR Appch)?

Can this be a form of a short-cut?
If cleared do Crossing Altitudes no longer play a role?
Does one have to have the Runway, Approach Lights in sight to request, as I can see no point other wise?
Once Cleared - does one have to remain in VMC or maint. contact with above?
What about aircraft separation and terrain clearance - will ATC still be required to monitor?
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Old 8th Apr 2010, 16:26
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If cleared do Crossing Altitudes no longer play a role?
Hmmm, that's what a TWA flight thought on an approach to Washington Dullas a long time ago.
The aircraft was descended straightaway to the final approach fix altitude, and struck a hill...all dead.
This was before GPWS, and this one accident was the primary driving force for GPWS implementation.

Better be careful...crossing restrictions are many times very necessary for terrain clearance.
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Old 8th Apr 2010, 16:46
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Brookfield Abused, what does your company Operations Manual say?
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Old 8th Apr 2010, 20:53
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Brookfield Abused, what does your company Operations Manual say?
Better be cautious...many airline ops manuals are sometimes in disagreement with the facts.
Long ago, TWA found out...the hard way.

An old saying...pay absolute attention to the details.
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Old 8th Apr 2010, 21:28
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In my book, a 'straight in' remains an IFR approach, normally accompanied by 'via the IF/FAF' or 'via XYZ VOR' and means you do not need to fly any procedure turns or the like, but you will obviously need to observe safe altitudes. I would also assume that ATC will provide traffic separation AND you will be given descent clearances.

A 'Visual' is just that, a VMC manoeuvre, use whichever beacons you like (or none) but you must be able to complete the approach in VMC.

So, to answer your questions about a 'straight-in':

Can this be a form of a short-cut? YES
If cleared do Crossing Altitudes no longer play a role?
NO
Does one have to have the Runway, Approach Lights in sight to request, as I can see no point other wise?
NO
Once Cleared - does one have to remain in VMC or maint. contact with above?
NO
What about aircraft separation and terrain clearance - will ATC still be required to monitor?
YES
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Old 8th Apr 2010, 21:56
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My understanding, in my very limited IFR experience, is the same as BOAC's, i.e., "straight-in" is probably a rather informal way of clearing you to the ILS without having to fly the whole procedure.

I'm answering in despite of my lack of experience because I remember requesting such an approach once, following my companion's suggestion. I was cleared to the ILS/localiser (can't remember the exact words), but not before being asked if I was visual with the ground (which I was)... I suppose that on paper ATC were still responsible for providing terrain separation but they sort of delegated that responsibility to me in the name of expeditiousness... just guessing though. I don't really know how it works.
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Old 8th Apr 2010, 22:41
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If cleared do Crossing Altitudes no longer play a role? NO
PT Barnum, long ago, said it best...'A sucker is born every minute.'
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Old 8th Apr 2010, 22:49
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In the UK a visual approach can be requested by the flight crew or offered by the controllers if ...can maintain visual reference to the terrain. So the crew don't necessarily have to be visual with the airport or even the runway. But if it was a visiting foreign crew, for example, then most controllers would be wary of approving a visual approach in these circumstances.

On the beach
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Old 9th Apr 2010, 00:12
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Straight-in (ILS or VOR Appch)?

If I am in VMC or better yet - CAVOK, I am being vectored for an ILS Apch., I have the runway in sight at the IAF and advise/request and get cleared for a "Visual Apch." - then min. Radar Vectoring Alt.(which usually only the Controller knows), OM Crossing Alt., Glide Slope and Loc. Deviations no longer play a factor (providing I remain under the Visual Stabilized Apch. criteria)? I would still be operating under my IFR Flight Plan, but have essentially advised ATC I require less of their attention, assumed more responsibility (terrain and traffic avoidance)?

On the Straight-in Apch, I was under the assumption for example RWY 18 is in use, I am cleared a 36 LOC or 36 VOR Apch and to circle for 18. To avoid this timing consuming ordeal, I have RWY 36 in sight, I can request a "Straight-in Rwy 36".... I would still be flying my IFR Flight Plan but essentially be flying a Visual on RWY 36 (most likely with a TWC).
OR
Would I just be required to request a "Visual for RWY 36"?

HOWEVER
If I am cleared an IFR Proc. which has a Proc. Turn. via the IAF, and I receive a Clearance to perform a Straight-in Apch. Then I can ignore the Proc. Turn, manoeuver, self vector myself directly to the Final Approach Course while maintain min. Altitudes or last assigned ATC vector alt.
I assume;
1. My IFR Flight Plan is still active.
2. I can be in IMC or in VMC.
3. ATC still provides AC separation.
4. ATC computer is so equipped, will monitor my terrain clearance.
5. I am still obligated to remain within Protected Airspace (ILS/VOR/NDB tolerances). Meaning for example - with full LOC deflection inside the FAF/FAP I would be required to perform a GA, UNLESS I was then truly VMC, had the RWY - lights, etc. and was Cleared a Visual?

Last one;
"Straight-in Visual Approach" - does not exist?

For me this is more a legality point of view. Essentially if I request, ATC Approves, crew reads-back, then we can legally carry out! Often SOP's/FOM's do not cover such finer points.

Last edited by Brookfield Abused; 9th Apr 2010 at 00:28.
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Old 9th Apr 2010, 01:26
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In the US, the term "straight in" in a approach clearance was a way to ensure the crew, joined the final course and did not fly a course reversal. It is described this way in the FAA AIM and is really a holdover from the early radar days.

I don't think there is any reference to it in PANS-OPS or Doc 4444. I wouldn't consider it a clearance for a visual approach, though

GF
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Old 9th Apr 2010, 01:53
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Does one have to have the Runway, Approach Lights in sight to request, as I can see no point other wise? Once Cleared - does one have to remain in VMC or maint. contact with above?What about aircraft separation and terrain clearance - will ATC still be required to monitor?
Folks,
A clearance for a visual approach is a specific clearance, with specific requirements and limitations.

Unfortunately, those requirements and limitation vary from country to country, and where applicable, the PIC should be thoroughly familiar with the local "rules".

The ICAO version is quite restrictive, the FAA version less so, and quite practical, unusually for Australia, the Australian visual approach is really quite flexible.

I know of no alternative, other than checking a country's AIP, to find the detail, Jeppesen is not always comprehensive on this one. As the ICAO is (to the best of my knowledge) the most restrictive, you could confine yourself to that, but it may cause delay to an arrival.

Tootle pip!!
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Old 9th Apr 2010, 02:08
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Brookfield Abused: I think you've gotten yourself into a dead end, here. You say "if I request a straight in approach", and then you ask us what you are actually requesting? There is no such thing as a straight in approach by itself. You can fly a visual approach straight in (what you normally do unless otherwise required for traffic or terrain or to stay visual), you can sometimes fly an instrument approach straight in (that is to say, without a reversal procedure (procedure turn, baseturn or racetrack)), but "straight in appraoch" on it's own doesn't make any sense. If you want to reduce your maneuvering to a practical minimum, the easiest would be to request a visual approach. If that not possible for some reason, be very careful about being "creative" with instrument procedures; if a straight in procedure is not published, there might be a reason for it.
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Old 9th Apr 2010, 02:11
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...Glide Slope and Loc. Deviations no longer play a factor (providing I remain under the Visual Stabilized Apch. criteria)?
Careful there.
Many larger aircraft (mostly widebody types) have a threshold minimum crossing height.
Get too low and the main landing gear can become tangled in the frangible approach light bits.
In addition, for noise abatement, approaches below the glidepath are many times frowned upon by airport authorities.
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Old 9th Apr 2010, 04:51
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From CHN (China) Operations perspective.

Ok - all very good points given and the big liability is the individual AIP's of each country. Too easy to miss something and then find yourself in deep serious trouble.
I was trying to apply this question to Foreigners operating med./hvy. AC in CHN (always positive radar control and under IFR Flt. Planning).
In CHN their is no noise monitoring!
However ATC does pay very close attention to your separation from AC and terrain.
All Apch, Dep., and Airport Controllers are Civi's under the jurisdiction of the military.
So in short I would never accept the liability of requesting a "Straight-in", nor a visual in day Ops. (Night visual forbidden) unless it is a simple base to final turn and one see's all and is familiar with the AP.
Also in CHN every airline monitors each flight via QAR data more then your wife would check your mobile phone bill.
Thanks all.
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Old 9th Apr 2010, 07:53
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Originally Posted by 411A
Quote:
If cleared do Crossing Altitudes no longer play a role? NO
PT Barnum, long ago, said it best...'A sucker is born every minute.'
- bit confused by a foreign (English) language and double negatives, maybe, 411? What is your (cryptic) point? Are you saying they do not 'play a role'?
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Old 9th Apr 2010, 08:15
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Are you saying they do not 'play a role'?
Negative.
Crossing restrictions should be strictly observed.
To do otherwise is foolhardy.

NB.
Double negatives is bad form
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Old 9th Apr 2010, 09:08
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My understanding for the UK:

As far as I recall a STRAIGHT IN approach is something that is instructed by ATC, and is a way of establishing the aircraft on the final approach track / localiser when it is already within 30 degrees (?) of that track. Perhaps an air traffic controller would confirm or deny this? It is conducted during VMC or IMC, and the step-downs / glideslope etc. must still be followed as per the approach procedure. As one poster has already stated, it's just a way of getting you on to the published final part of the approach without following all the published teardrop / procedure / radar vectored turns because you are already situated in a roughly straight in position.

A VISUAL approach is an entirely different method where the pilot requests to continue the approach with visual reference to terrain, foregoing the requirement to adhere to any published IFR tracks & MSAs. From an ATC perspective the pilot need not be in sight of the runway but a reasonable assumption must be made that he is able to continue ultimately to the airport by sole visual reference (or words to that effect). Most responsible airlines however stipulate that approach lighting or the touch down zone must be in sight.

During a visual approach I agree using nav aids, adhering to the published glideslope & meeting minimum altitudes is a reflection of professional airmanship, however I have met pilots who seem to become overwhelmed with the perceived "fun" of a visual approach and abandon many of their instrument and nav aid resources as if they no longer have a use. GPWS aural "GLIDESLOPE, GLIDESLOPE" is the usual tell-tale sign of such cowboys, worsened by their dismissive remark of "disregarding.....visual..."

Last edited by Kiltie; 9th Apr 2010 at 09:22.
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