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yanjing
7th Oct 2015, 17:08
hallo everyone ,


some VOR app final course is difference from runway course(eg. 5 degrees).


when visual contact above MDA ,can I turn to runway centerline earlier


(for exgample 1500 feet)? ( stand on runway centerline may feel more


comfortable.)


any policy or rugulation says that is ok ? or not ok ?


thanks

Skyjob
7th Oct 2015, 19:20
Yes you can.
Especially within the defined circling area for your aircraft type.

yanjing
7th Oct 2015, 19:35
thanks !


another question :


continue fly via VOR instrument course untill meet runway centerline,


or

turn earlier to runway centerline ,which one is better to do ?

RAT 5
7th Oct 2015, 19:51
Visual is visual. You're asking about obstacle clearance limits: are you safe to make a turn. If you're visual you decide.

peekay4
7th Oct 2015, 22:12
In many cases you must turn and commence descent well prior to the MAP in order to land at a normal glide angle. (Assuming you have the runway environment in sight).

See for example the "Visual Descent Point" (VDP) concept.

Bobermo
7th Oct 2015, 22:34
Interesting question, I believe when you are visual you can line up with the runway.

Similar question:
Last week I was flying a VOR approach with a 3.4 degree descent angle. The papi was set to a 3 degree angle. From when is it allowed to pick up the papi (by doing so going below the VOR approach)?

overstress
7th Oct 2015, 22:50
When visual.

de facto
8th Oct 2015, 12:30
When you are visual then vor goes out the window,you may join the centerline and joon the 3 degree from the steeper earlier...
Just be aware of those airports that have displaced threshold and steep descent for noise reasons..

ChickenHouse
8th Oct 2015, 13:02
I always thought this is dependent on the specific airport and its crowded or not airspace?

Skyjob
8th Oct 2015, 21:18
Last week I was flying a VOR approach with a 3.4 degree descent angle. The papi was set to a 3 degree angle. From when is it allowed to pick up the papi (by doing so going below the VOR approach)?

I would be careful when self maneuvering when not within the circling area as the PAPI are not protecting you then.

Visual is visual, so self positioning is allowed but you are solely responsible for terrain clearance and in some cases this is not ensured when descending below the approach angle which is raised for A/B/C/../Z reason.
Excellent positional awareness and location knowledge may be required to understand the true reason why the angle had been raised in the first place (village on short final, mast on the extended approach track, ...)

And remember to think thrice before declaring visual at night for the same reasons when outside of circling area as visual contact with ground cannot be maintained.

m39462
8th Oct 2015, 22:55
I would be careful when self maneuvering when not within the circling area as the PAPI are not protecting you then.

Indeed, since being visual on final may only mean you can see some runway lights and not necessarily obstacles, it may be wise to remain within the circling area or another protected area. With respect to the original post, it might be the visual maneuvering area associated with the offset approach. TERPS has a nice picture of one (http://www.jetcareers.com/forums/attachments/terps-thingy-pdf.12665).

peekay4
9th Oct 2015, 05:00
The Circling Area and the PAPI obstacle clearance area is not directly related.

Depending on the circumstances (and jurisdiction) you can be within the Circling Area but outside of the PAPI's protected area. Or vice versa.

In the ICAO world PAPI provides protection up to 7.5 km (4 NM) for shorter runways and up to 15 km (8 NM) for longer runways, within +/- 15 degrees from the runway centerline.

In the FAA world PAPI provides protection up to 4 SM (3.5 NM) within +/- 10 degrees from the runway centerline.

imriozer
9th Oct 2015, 06:59
Don't tie the papi and the approach course..
There is a reason why you were given VOR Z or VOR Y (let's say the runway course is 080, Z is 075, Y is 070) and not ils or rnav, it can be because of terrain on one side of the course or maybe one or two restricted of dangerous areas in close proximity to the airport...

At night I will turn visual only in the circling area

goeasy
10th Oct 2015, 04:51
Be sure you're visual with correct runway... That's why some airlines or TRE recommend keeping on approach track to MDA.

RAT 5
10th Oct 2015, 10:01
Be sure you're visual with correct runway... That's why some airlines or TRE recommend keeping on approach track to MDA.

True; shades of Aldegrove's easterly runway a few years ago. However, it also depends on your height and distance out when you become visual. To make this preference a blanket SOP can not always be the best advice. If the inbound track is significantly off the centre-line, and MDA quite low, it would lead to some close-in manoeuvring an low level when it would have been much easier to align the a/c much earlier and quite safely.

Making such an issue an SOP might cause crews to 'stop thinking'. I had one such experience, not caused by an SOP, but by not thinking. We were approaching an airport in flat country where there was an ILS on one end and nothing on the other. The weather was fine with a cloud base >5000' and endless visibility. The wind required the non-IFR runway to be in use and so the ATIS said it was ILS with circle. The DA for circle was 600'agl. The newish F/O was PF and set up & briefed a circle approach. After listening for quite a few minutes to this drone-on I asked "what will you do if you are visual at 4000'? What about a visual circuit?" The reply was, "ATC says it is a circle approach and by doing one I know I'll be in the correct slot on finals." I pointed out that he was on the outside of the base turn, and 600' gave little room to make any corrections. 1500' visual circuit is also a timed manoeuvre so you should also be in a good place on finals and with more room to adjust. It would also make less noise, use less fuel and be a safer manoeuvre. After much disagreement, some cajoling and finally an order, he performed a visual circuit with much grumbling as to how difficult it was to 'get in the slot'.
My point is he had stopped thinking and was planning to do exactly what ATC had said the approach was. He didn't understand that ATC can not declare a visual approach for IFR traffic at an IFR airfield, but you can.

Bobermo
10th Oct 2015, 10:39
Interesting answers, thank you all.

Food for thought the next time I come across situations like this:ok:

cf6-80c2b5f
12th Oct 2015, 08:47
You may also be interested in this post from five years ago regarding the VOR22L approach at KJFK. It too is offset from the final course, probably due to La Guardia's airspace. There were a number of opinions given, including one from a JFK tower controller, but in the end there appeared to be no clear consensus on the "correct" answer.

http://www.pprune.org/tech-log/427383-transitioning-visual-before-mda.html