Problem with VOR/DME approachs, , please help..

[flame_bringer]

Lately , i started practising on VOR approachs using approach plates on the flight sim 2004 , and iv been having a great deal of difficulty to successfuly accomplish the approachs , here's my main problem:
lets take princess juliana int as an example of an airport on which im trying to land using VOR.
http://www.avsim.com/pages/0409/Wilco/Approach-plates.jpg
Thats how i interpret it
First off it says fly inbound the VOR station untill you pass it , then select a heading of 128 and once you establish this heading wait for a certain time then capture the 308 radial and fly inbound the VOR station again , once you pass the VOR station fly the 318 radial outbound untill you're 7 nautical miles off the VOR station then capture the 96 radial and fly inbound , and thats it you're supposed to be aligned with the runway . Thats how i understand it.
However when i try to implement all this , i wind up not aligned with the runway for some reason :S
So i figured i'd go for 93 instead of 96 since it says runway centerline is offset 3 degrees frm the Final course , still noo luck , i tried 99 just in case if its offset from the opposite side and again no luck.

(Note , i tried many other approach plates for different airports and i still get the same problem ( not aligned with the runway in the end )).

Anybody got a clue whats wrong and how am i supposed to accomplish this approach? is my interpretation to the plate correct ?
Any help would be greatly appreciated

[Lafyar Cokov]

On many VOR approaches you are not exactly aligned with the runway - as they are known as non-precision approaches. You are expected to make all adjustments to line up in the visual segment - which in this approach would be from a height of 600ft QNH or greater. As explained on the caution on this plate - the Final Approach Course actually intercepts the RW centerline at 7nms from the threshold.

The reason for this is in the airfield picture at the bottom right of the chart (as is the reason on nearly all VOR approaches) the VOR beacon is not on the runway but off-set from it somewhere on the airfield - therefore the approach actually takes you to the beacon not the runway.

Hope this is of some help


LC

[flame_bringer]

And what am i supposed to do to line it up with the runway :S adjust its heading manually ?

[rogerg]

You look out of the window!

[flame_bringer]

Iv been trying to line it up manually by looking at the runway merely for 4 hours in a row and out of 21 attempts none succeeded,.
Very difficult really :(
Any tips on how to line it up manually? external references i could follow or anything ?
All i know is the PAPI light which gives me an indication of the glide slop , is there is any light or something that gives me an indication of the localizer.
Please i need some help

I deseprately want to perform a VOR landing , and i did alot of reading on it its just very difficult to do :(.

[flame_bringer]

Thats it i gave up
anyways
Thanks for all the replies

[madlandrover]

As other posters have said, any beacon approach (VOR, VOR/DME, NDB, NDB/DME) is an approach to the beacon, not to the runway. In theory the approach should be designed so that when you reach minima you are on the centreline - doesn't always happen of course, but that's the plan. This means that when flying the approach in marginal conditions you should find that on looking for visual references when approaching minima you should only have to make a minor heading adjustment to track to the runway. It's important to note that there is no localiser with a VOR approach - localisers only apply to ILS (and, I believe, MLS - perhaps someone could confirm this?) approaches which are designed to take you right down to the runway.

Non-precision approaches take you to a point where you can become visual safely and then make any necessary adjustments, whereas precision approaches (offset ILSs excepted of course!) should result in you making a bare minimum of adjustments between becoming visual and landing.

[flame_bringer]

Well my main problem is the minor adjustment that i have to make upon reaching the point where i can see the external visual reference .
I tried my best to align it using the heading select mode but no luck .
It says on the approach plate that the runway is 3 degrees offset from the final radial , does that mean that i have to adjust my heading to 3 degrees less than the final course ?
What do you guys usually do at this point ? do you revert to manual control of the aircraft as soon as you see the visual reference and try to align it all manually ? or you adjust the heading on the heading select mode ? and if you adjust the heading how do you guys determine the correct heading adjustment that aligns you to the runway ?

[flame_bringer]

I finally managed to land it
I actually landed it twice
yea i guess i needed quite a bit of practise
Time to try NDB approachs :D
Anyways thanks you all for all the helps
regards

[AerocatS2A]

For that final visual segment there's no real rule you can follow or anything, you just have to look at the runway and judge it. I'd do it by flying manually rather than on autopilot with the heading bug, but manual flying is a lot easier in a real aeroplane than in FS200X.

You don't need to fly the initial holding pattern either, that's the bit where you go over the VOR then outbound on 128 and inbound on 308. If your inbound course is close to the first outbound course on the approach (within 30 degrees either side) you can just go direct to that outbound course.

Also, the way you enter the holding pattern depends on your initial track to the VOR, you don't always just go straight on to 128.

[flame_bringer]

AerocatS2A
yea its a hell to fly manually on the flight simulator
I'd love to try it on real aeroplanes but alas im not allowed:(
And i still could not master the visual segment many times when i try to land i land it veered to left of the runway or to the right of the runway :S
Also with regards to the way i enter the 128 heading for the holding pattern ? what do you mean by the way you enter it relies on your initial course ? how do i know the right way of entering it as per the intial course from the aproach plate ?
By the way im not a pilot and im not doing a pilot training im just an avionics engineering apprentice but i like aeroplanes thats why im trying to learn pilot stuff.

[Tinstaafl]

Holding pattern entry is based on your heading when you cross the holding pattern fix which, in turn, is related to the direction from which you come. The type of entry to a pattern is limited by the need to constrain the aircraft within protected airspace and for the pilot to have sufficient time & space to manoeuvre, and/or navigation information to fly within tolerances. Using specific holding pattern entries for different directions of arrival help with those constraints.

Google 'holding pattern entry', 'parallel, teardrop, direct holding pattern entry' or 'sector 1, 2, 3 holding pattern entry' or similar. Wikipedia also has a page about it. Each one of those three is specific to an arrival direction (actually, each one covers an arc) and together the three arcs cover 360 deg around the holding fix**. Arriving from a direction that is within the arc for a Sector 2/Teardrop entry? Follow the Sector 2/Teardrop procedure to enter the holding pattern. Arriving on a heading that falls within Sector 1/Parallel? Then it's a Sector One/Parallel procedure to be used.

The Sectors are standardised & oriented with respect to the inbound track of the holding pattern. It doesn't matter what the holding orientation is because the entry sectors follow the holding pattern. Bit like your left ear is always on the left side of your head no matter which way you face.


**Slight caveat: there's a +/- 5 deg overlap where each sector meets. You can use either sector's entry procedure if you're within the overlap.

[flame_bringer]

Thanks
i guess i have to practise on how to enter a holding point then .