When to line up with runway if the VOR final course is offset?
 

Hi all,

When I am flying a VOR approach which is several degree offset of the runway. May I deviate from VOR guidance and line up right after visual contact with the runway? Or, I should keep on the VOR final approach course until MDA or some other point, then go visual and line up? Is there any regulation concerning this?

Thank you!


Edit:
Thank you all for replying. For the airport I am planning to go, the VOR is offset due to a mountain alongside of final. It is NOT VOR-A, which require a circle. But only 7 degree offset. I would like to go visual and lineup, make it stable as early as possible. But if so, I may trigger the annoyed EGPWS caution, then have to do a lot of paperwork to report and “justify”. Since I am still under IFR approach even though it is VMC outside and I can see the runway and mountain clearly, I am anxious if I violate any regulation if I deviate from the VOR lateral guidance too early. I can not find any regulation concerning this. It would be appreciate if you can list one. Thank you so much!

Edit:
Thanks to mmm345. For Australia, please refer to #24. But for other countries, I still have not found any specific regulation.

If you are visual I would say go visual.

I seem to recall Heraklion RW 27 was one of many.

It's an instrument approach. The trajectory intersects the extended runway centerline appropriately and the profile enables a controlled descent with stable rate towards the threshold.

What's the urge to deviate? In other words, go visual as long as you keep following the procedure you have been cleared for. :ok:

The VOR might be offset due to an obstruction on the extended centreline. Dalaman 19 is an example.

Stay on the procedure until you can make a normal visual approach to the runway.

Once you deviate from lateral (and vertical) guidance you’re on your own.
It’s easy to calculate a VDP (Visual Descent Point ) if one is not depicted.
Your HAT (Height above Terrain) x 3 equals distance.
So with an MDA that is 500’ above airport elevation your VDP is at 1.5 NM.
If the weather is significantly better then minimums for the approach I’ll consider to line up further out but still using the 3:1 rule.
So at 1500’ AGL I’d have to be at 4.5 NM.
Once you practice this a couple of times it’s real easy.
Gives you a 3 degree descent angle and a stabilized approach.

thegypsy

Thank you for your reply!
Kinda like LGIR, the terrain around my concerning airport is very complex. They put VOR 7 degree offside to keep distance with a high mountain alongside. So I am wondering what is the best time to line up without causing any EGPWS cautions, either violate any regulation.

Peter G-W

Indeed! So, if I lineup too early, I may trigger the EGPWS, that would be a BIG trouble for me in our company. They don’t care if you are visual or not.

B2N2

Thank you for your useful tips!

B2N2

You could do all that or just look out the window and land the sucker.

Dorf

Haha, good to review this flight school knowledge though. But it is getting more and more hardly to find VDP in nowdays chart. Everything is changing to CDFA or GPS with vertical guidance..I suppose ILS may disappear in some years.

FlightDetent

Agree! But a lot of captains in our company, especially those from Air Force, are soooo eager to go visual. Seems they even wanna shut off all the screen as long as they can see the runway. So I need a regulation clause clearly saying they may or may not deviate from the guidance to avoid both of us getting into trouble.

B2N2

Be careful with that one, as there are plenty of VOR approaches deviating from the standard 3° for a good reason, mostly being terrain - fe. TSL 28/34 with 3,80°, or OPO 17 with 2,80°...

Nonetheless, if the weather's fine and you briefed it, I see no problem in continuing / aligning visually and not staying madly on the VOR App all the way to MDA.

Fly the offset. It's there for a reason.

It is. I usually leave it til I'm within the circling range then line up.

In Australia at least, when flying a non-precision approach ( ie. a VOR Approach), you can only align with the runway centreline if not already aligned when within the cirlcing area, continuously insight to ground/water and visual ref. with the runway environment can be maintained. However, if the offset angle is >5 degrees, the approach coarse will intersect with the final approach track not less 1400m of the runway, making it not really nessecary to deviate from the inbound coarse any earlier then when the approach naturally intersects with runway track.

It is not permissable to simply discontinue the cleared NPA and decide to manouvere visually when outside the circling area in less than VMC but still visual ( ie. poor visibility or not continuously in sight of ground/water).

Dorf

Good reply - practical solution to a practical problem!

flyfan

11072437]B2N2

I couldn’t tell you without seeing the instrument approach plates.
In any case once passed the FAF a descent to MDA should not get you in conflict with terrain.

flyfan

I couldn’t tell you without seeing the instrument approach plates.
In any case once passed the FAF a descent to MDA should not get you in conflict with terrain.

B2N2

Dude, check VNKT VOR 02

Hmm. He says should and even if it was must that does not equal to will. On the line, everyone needs to keep checking facts against pre-conceptions. Even the correctly trained ones. Truly well spotted. I'm sure B2N2 omitted the additional "unless there are step-down fixes published" for brevity (didactic reasons).

https://cimg7.ibsrv.net/gimg/pprune....72be0b49c2.png

What a peach. Dropping from FAF [D9=8900 ft - not on the picture] to the next step-down fix of 5510 [D3] would indeed compromise the OCAs. Bit of work to dive steeper than 5,3°, but it surely can be done. Those OCAs shouldbe made into step-down fixes.

BTW it is no longer clear to me if it is lateral or vertical being discussed above under "following procedure".

Haha, thank you for your reply. Of course, I am concerning lateral guidance since VOR doesn’t have glide slop. And mmm345 answered my question so well! I am still looking for the counterpart in FAR. Should be similar. In spite of this, thanks B2N2 help us review VDP and the formula. While CDFA is taking place VDP. I nearly forget this theory.

BTW, where did you get this lovely chart? Far better than Jeppesen. I tried use VNAV to fly this approach several times, but it always end up with very high speed. Seems by manual is still the best way. But it will greatly increase the work load. Especially when fly in this narrow valley. Not quite correspond to the topic, but very glad to talk about it in another thread if anyone interested.

As per your example, following the vertical profile (#exists) is perhaps of greater importance than lateral. Or the margin for error is less, if you will, namely for the GWPS case.

There are 2 or 3 more companies other than Jeppesen producing aeronautical charts for public use. Each of whom tried to enter the market with a superior product and the hard work paid off. The above is Lido.

What is your type?

AIP Nepal


https://cimg6.ibsrv.net/gimg/pprune....925c2aa0fb.png

Cool chart! Has tons of more details than Jeppesen. Surely the vertical path is very very important here. That’s why I can not agree with diving after FAF is always safe.

Actually they have RNP AR procedures there. Very easy and smooth to fly. All you need to do is having a cup of coffee, and let the airplane do all the job. However, it is too costly to get certified. So we have no choice but follow this last century tech guidance.

My type is G550 and G650. But both of them will be invalid next month. And our cooperate sim center is either shut down, or holding an out of date certification without anyone can go there to inspect. That means I will be semi-laid-off soon. What a tough time for all the aviators.

Ffs
 

Surely if you are visual and can remain so then why would there be a problem, just land the thing. I always thought the point of landing was to touch down somewhere where its safe, who gives a Monkeys if you followed the 7 degress Vor offset until the end, you can see what's there so use it. And yes I have landed in nepal alot of times and it's only difficult if you make it so.

To be fair, i see where your coming from but i think there is an important difference. Im from AUS so it might vary globally

however lets say yo get to the bottom of an instrument approach and its completely clear, clear, no vis problems or clouds and your in day vmc, it satisifes the operations below LSALT requirements ( 4. Day VMC of the CAR's in AUS), and as a result you can do what you want.

However, if you have been cleared for a certain IAP at a controlled AD, they expect and you are required to follow the IAP and its asscoiated rules with aligning to the centreline ( unless request and recleared VAP), which is AUS is ( within circling area, visual ref to runway and continuously insight Ground and water). Additionally, if by night or in less than VMC, ( you can be visual with the runway yet in less than VMC by means of less than 5km vis or not in sight of ground/water below 2000ft AGL), you have to follow the IFR IAP alignment with runway following a NPA offset approach Requirements.

The rules are written for a reason, and i totally get that lets say your half way down the approach, break into clear skies and perfect vis at some uncontrolled AD and you can now conduct a VAP, thats cool as long as you can satisfy the VAP requirements, ( 5km vis, clear of cloud, insight of Ground and water etc). However , if you are cleared for a certain IAP or at a uncontrolled AD however are conducting an IAP and sight the runway in less than VMC, you must follow the approariate NPA alignment with centreline procedures.

In Australia they are.

So basically: If you're on an instrument approach, you should fly that. The procedure itself allows for neat track alignment.

Not a rule overly complex to remember. :ok:

Some discussion also available on the JFK VOR 22 thread, sure someone grabs a link quick.

avtur007

You will not say this if someone is checking your QAR for every single flight! And they DO care where did you touch down. They will warn you in 72 hours if you don’t land within 2000ft. Plus, they will monitor your speed, altitude, track, timing of configuration, taxi speed, G-load when touch down, etc. etc. Even the pith up rate during takeoff, should be within 2.5-3.5 degree/s. If you don’t operate within their standard, you will get in trouble. Our chief pilot was fired just because he triggered PULL UP but continued to land at Queenstown (NZQN), even though it was perfect VMC outside. Moreover, we don’t have a lot of flights during pandemic. So, everyone is keeping eyes on you when you fly out. And our boss is trying all his best to find a excuse to fire some one to save money. Nobody want get **** during this tough time.

Other than that, I do agree going visual is the easiest way. But I insist it is not always the safest way. If I have any doubt, I will find the regulation, and obey the regulation. Fly like a lawyer, not a cowboy. I think this is the best way to protect myself and my career during these days. That’s why I am asking here.

mmm345

Thank you so much mm345! It sounds very reasonable. However, I searched the whole ICAO 8168 and FAR, still can not find any specific clause concerning this. Still working on that

Sounds like a very poor “just culture” running around instilling fear instead of safety habits. I find it hard to believe, but not impossible, that a US operator would be using a FOQA program as termination tool. Yes, continued intentional violations must be dealt with but there needs to be due process.

Our aircrafts are N-registered, but not a US operator. I always think they fear because they know less. They want us to be a robot rather than a human.