Hi all, I have a procedural question pertaining to doing a ILS approach with with a VOR/NDB transition located at the airport.

 

When you're approaching the VOR/NDB, you then fly the requisite "tear-drop downwind" and make a turn to intercept the glide-slope and localizer.

 

What is the standard procedure for flying such an approach when flying the tear-drop leg requires a turn of greater than 90 degrees? Will the plane just manage the sharp turn? Or is there another way to do the approach (and if so, what FMC setup is required?)

 

Thank you,

Sam Kharey

A tear-drop turn is 30 degrees.

 

It depends on which side of the Procedure turn I am entering the approach.

 

If I enter the approach from the non-procedure turn side I would enter it the same way I would enter holding by crossing the fix and turn outbound on a course parallel to the inbound course. I would fly this heading until passing the Outer Marker then turn inbound to intercept the LOC.

 

If coming form the Procedure turn side I would cross the fix, track the LOC outbound until the Outer Maker, make a 30 degree turn away from the LOC (on the procedure turn side) for one minute then turn back toward the LOC .

 

All turns need to be standard rate turns (constant IAS) and this can vary from approach to approach.

 

It might be easier to explain if you could provide a specific approach and aircraft location. <g>

 

Billy Bluestar

Two possibilities here. If it is programmed into the FMC, the autopilot can fly it. If hand flying, you do a rate one turn which is a turn of 3 deg per sec. In this case, the actual bank angle to use is related to the aircraft speed. An easy calculation is TAS/10+7 or TAS/8+3. Using 180kts as an example, the AoB would be 25deg

 

Craig

It might be easier to explain if you could provide a specific approach and aircraft location.

 

Hi Billy,

 

Please refer to the approach plate for runway 9 found on page 26:

 

http://www.google.ca/url?sa=t&rct=j&q=eggd%20charts&source=web&cd=1&cad=rja&ved=0CC4QFjAA&url=http%3A%2F%2Fva-transaero.ru%2Ffiles%2Fcharts%2FEGGD.pdf&ei=YT8NUaP_BoaKjAK9koDYCA&usg=AFQjCNFxpgXYYV1ub6aq8pV1Y-UnFYAw1g

 

Assume that my aircraft is situated due north of the VOR, and I am flying towards to VOR at say, heading 180 (south). How exactly would I fly the procedure?

 

Do I overfly the VOR, fly outbound on radial 135, and make the turn to intercept course 270 back over the VOR, and then 284 to eventually join the ILS?

 

If so, how do I set the part in red above in the FMC of the NGX?

 

Thank you,

Sam Kharey

This might be quite helpful when it comes to procedure entries. (there are two parts)

 

This might be quite helpful when it comes to procedure entries. (there are two parts)

 

 

Bogdan,

 

Thank you very much - that was most helpful. Now that I know there are (three) different ways of flying the procedure turn based on the direction of arrival, can you advise how to setup the FMS to follow the required entry pattern?

 

Thanks,

Sam Kharey

Hi Billy,

 

Please refer to the approach plate for runway 9 found on page 26:

 

http://www.google.ca...q8pV1Y-UnFYAw1g

 

Assume that my aircraft is situated due north of the VOR, and I am flying towards to VOR at say, heading 180 (south). How exactly would I fly the procedure?

 

Do I overfly the VOR, fly outbound on radial 135, and make the turn to intercept course 270 back over the VOR, and then 284 to eventually join the ILS?

 

If so, how do I set the part in red above in the FMC of the NGX?

 

Thank you,

Sam Kharey

 

I guess that what you describe is pretty much the right thing to do. At least it look logical.

 

Just note that NGX is CAT D so it's the 290 radial that you should follow...

 

 

Bogdan,

 

Thank you very much - that was most helpful. Now that I know there are (three) different ways of flying the procedure turn based on the direction of arrival, can you advise how to setup the FMS to follow the required entry pattern?

 

Thanks,

Sam Kharey

 

Well, I'm not an expert when it comes to the FMS but if you connect the IAF which can be a VOR or NDB with the STAR or ILS approach, the FMS should calculate everyryting by itself

and fly the right entry. If not, do it manually by tuning in radials and calculating everything by your own - as it has been shown in the tutorial above.

 

Cheers.

 

Just note that NGX is CAT D so it's the 290 radial that you should follow...

Wait, isn't it cat C, the neighboring thread has something on it. Or am I mixing something.

It could be whatever your approach speed is that day...

Wait, isn't it cat C, the neighboring thread has something on it. Or am I mixing something.

 

The category of aircraft depends on the the Vref (which of course changes depending on weight).

• Category A: Speed less than 90 knots.
  
• Category B: Between 91 and 120 knots.
  
• Category C: Between 121 and 140 knots.
  
• Category D: Between 141 knots and 165 knots.
  
• Category E: Speed 166 knots or more.
  

Therefore, the 737-800 can be either C or D.

 

Sam Kharey

Do I overfly the VOR, fly outbound on radial 135, and make the turn to intercept course 270 back over the VOR, and then 284 to eventually join the ILS? If so, how do I set the part in red above in the FMC of the NGX?

 

You do if you are exiting a holding pattern. Also you may notice the dotted line which is more easy alternate way to exit the holding.

It's possible to enter hold exit into FMC, but too much work. I think you will be vectored because procedure turns are rarely used today.

 

Here is a way to fly it from ICAO doc 8168. Start timing right before first turn at BRI NDB, turn to 135, at 1min 15s begin turning to 315*.

 

The category of aircraft depends on the the Vref (which of course changes depending on weight).

• Category A: Speed less than 90 knots.
  
• Category B: Between 91 and 120 knots.
  
• Category C: Between 121 and 140 knots.
  
• Category D: Between 141 knots and 165 knots.
  
• Category E: Speed 166 knots or more.
  

Therefore, the 737-800 can be either C or D.

 

Sam Kharey

 

 

B738 is cat C for all normal circumstances. ICAO DOC 8168 explains the classification.

Just to clarify:

 

 

Found here: http://forum.avsim.n...m-cat-i-and-ii/

Is there no transition selectable in the FMC?

 

If not, you could either build it with BRI290/8 and then build an inbound leg or simply join the LOC after turning from the BRI 290.

 

In the end, it doesn't really matter how you follow the course, just don't go out too far or bust altitudes.

From a buddy who is on the B737-800 - CAT C for straight in approaches, CAT D for single engine and Cirlcing Approaches. Some airlines may do it differently.

 

For the approach coming from the north and able to slow to 185 KIAS I would most likely make a left turn at BRI to heading 274 until 8 DME then turn inbound to intercept the LOC. I would fly this approach using raw data. The FMS is nice, but raw data is much easier and cleaner in a lot of instances.

 

Billy Bluestar