Converging ILS...WTF?

[cybourg10]

What is the definition of a converging ILS? I can't find a definition in my jepps and the only airport where I see a converging ILS plate is for DFW. Take Converging ILS Rwy 35C (kdfw) for example, it is identical to the normal ILS Rwy 35C plate in every way except that it says simultaneous approach authorized w/ CONVERGING ILS Rwy 31R and CONVERGING ILS Rwys 36L/R. Does it mean that a another ILS approach is in use to a runway NOT parallel (or more than a few degrees off) to the course of the approach on the plate? Sorry if none of this makes sense, it has been a long day of studying for finals and an interview....

 

[minitour]

The approach courses converge. (meaning they eventually run into each other...follow the extended centerlines of 31R and 36C and they bang into each other.....don't want an airplane to do that.)

PIT Has 'em too...I'm sure there are others.

Usually the missed approach procedures will be different (at least from what I've seen) than the regular approach procedures.

It's not a big deal...just read the plate and follow the needles. Chances are you won't even notice it as a "different" approach.

-mini

 

[MauleSkinner]

What is the definition of a converging ILS? I can't find a definition in my jepps and the only airport where I see a converging ILS plate is for DFW. Take Converging ILS Rwy 35C (kdfw) for example, it is identical to the normal ILS Rwy 35C plate in every way except that it says simultaneous approach authorized w/ CONVERGING ILS Rwy 31R and CONVERGING ILS Rwys 36L/R. Does it mean that a another ILS approach is in use to a runway NOT parallel (or more than a few degrees off) to the course of the approach on the plate? Sorry if none of this makes sense, it has been a long day of studying for finals and an interview....

MSP has 'em too...runways 30L (don't know about the right) and 35...the departure ends of these runways get pretty close together, and aircraft going missed would also get pretty close.

You might doublecheck the minimums...at MSP, the Converging approaches have higher DH's than the normal approaches (and maybe different missed procedures on one of them, I can't remember for sure)...lets the airplanes start avoiding each other sooner.

Fly safe!

David

 

[SkyBoy1981]

The approach courses converge.

PIT Has 'em too...I'm sure there are others.

Usually the missed approach procedures will be different (at least from what I've seen) than the regular approach procedures.

It's not a big deal...just read the plate and follow the needles. Chances are you won't even notice it as a "different" approach.

-mini

Except that the minimums are considerably higher than a normal ILS. If PHL weather is too low to use the converging ILS 17/9R in their operations they are forced to use one runway for all arrivals, which is why there can be so many delays there at times.

 

[cybourg10]

Thanks for the quick replies, the missed aprroach procedures for the normal 35C approach are the same as the converging 35C ILS but the missed approach procedure for the converging ILS 31R are slightly different than the normal approach....obviously to avoid a/c on the missed on 35C and 31R from getting too close. One other question, will ATC assign you the converging ILS approach or is it up to the crew to know that parallel approaches are in use and that they need to use the Converging ILS missed procedures?

 

[SkyBoy1981]

It is assigned and usually broadcasted on the ATIS that they are in use.

 

[cybourg10]

Makes sense...thanks.

 

[Hook 'Em Horns]

This explains it pretty well: http://www.faa.gov/ats/asc/publications/95_ACE/Chap_03.pdf

Paragraph 3.7. Some of the above replies were correct. Higher minimums are required due to MAP overlaps.

Anyway, hope that helps.

 

[Joblio]

Does anyone know... Is special crew training required to do those, like an ILS PRM approach?
Thanks!

 

[Hook 'Em Horns]

I couldn't find anything that said special training is required.

 

[mnixon]

As far as special training goes, I had to sign a letter saying that I had the special training for a 135 freight gig.

 

[Rez O. Lewshun]

This is also why you bug runway heading while on finale and not wind correction angle...

 

[pilotguy733]

PHL also has converging appchs...