IAP Question

[minitour]

Lookin at some approach plates tonight, I came across PIT. I saw the "Converging ILS 28R & 32" and (I believe) Cat II (and maybe) III for 10R.

Really a stupid question, but when you're on these approaches, do you get a specific clearance from approach or is it on the arrival ATIS that these are in use?

IOW:
Does Approach give you: "Turn right XXX maintain XXX until established cleared converging ILS 32 approach" or is it just "...cleared ils 32 approach"

for the CAT II and III guys same question: "...cleared CAT III ILS X approach" or just "cleared ILS X approach"

My original assumptions would be for the converging ILS approaches it would be on ATIS and you'd get a clearance from Approach for the converging approach (so you don't go missed the wrong way). but for the CAT II and III stuff I would assume it would just be "cleared ILS X approach"

...am I right?

thanks for the help!

-mini

 

[FracCapt]

You will be cleared for the "converging ILS". At many airports, the missed approach is slightly different on a converging approach than a non-converging approach to the same runway.

 

[getonit]

I believe the minimums are also different, the converging is usually higher. I am assuming it has something to do with approach proceddures and how close everybody can get.

 

[gfvalvo]

Lookin at some approach plates tonight, I came across PIT. I saw the "Converging ILS 28R & 32" and (I believe) Cat II (and maybe) III for 10R.

Really a stupid question, but when you're on these approaches, do you get a specific clearance from approach or is it on the arrival ATIS that these are in use?

I recall that there are other differences with the Converging ILS approaches: separate tower freq, listen only - don't talk, if one of the aircraft starts to stray off coarse then the OTHER plane gets sent on a go-around. I'm sure the airline guys get special training for these. I might think twice about accepting one myself depending on recent experience / practice. Can ATC assign these to anyone, or is extra training/certification/equipment required like CAT II/III?



Greg

 

[Oakum_Boy]

A PRM is different from a converging. I believe a 91 guy can fly it if he can comply with all the items on the briefing page. 121 have a short course on all that stuff.

 

[Axel]

I recall that there are other differences with the Converging ILS approaches: separate tower freq, listen only - don't talk, if one of the aircraft starts to stray off coarse then the OTHER plane gets sent on a go-around.

Respectfully: You are confusing the converging ILS with the PRM close parallel ILS. The converging approach(s) are to non parallel runways with the planes approaching the airport toward each other (converging). These are separate procedures with separate charts from the normal Cat I ILS. The minimums are higher resulting in a missed approach point further from the airport, thereby preventing a traffic conflict in the event of a miss.

The PRM (Precision Radar Monitor) ILS allows planes to fly ILS's to parallel runways that are close together. Without PRM, the finals would have to be staggered in order to provide lateral separation. With PRM, there is a dedicated controller monitoring a "no transgression zone" between the finals. This allows the planes to fly parallel approaches as close together as 2500 feet. If one deviates toward or into the NTZ, the monitor controller breaks both out of the approach and away from each other. There is a separate monitor frequency that is used simultaneously on a second radio in conjunction with the normal tower frequency in order to ensure a breakout instruction is not accidentally stepped on.

As for Cat II & III, I defer to someone with experience in that regard as I have none.

 

[172driver]

As far as the Cat II and III, the aircraft and pilots must be certified. Extra training for the pilots. Extra inspections and tight tolerances for the aircraft avionics/autopilot. You will be cleared for the specific approach...'cleared for the Cat II ILS Rwy 32.' Won't happen unless you ask for it or the wx is hovering around or below Cat I mins.

 

[Lead Sled]

A PRM is different from a converging. I believe a 91 guy can fly it if he can comply with all the items on the briefing page. 121 have a short course on all that stuff.

"91 guys" have to have the training as well. It doesn't take long. PRM is the FAA's version of close formation flight. There are a few places like PHL where they're used a lot. If you can't accept the approach you go to the end of the line... "Expect further clearance sometime late tonight."

'Sled

 

[minitour]

Thanks guys...not sure why I was so curious...perhaps dorky pilot?

(argh...where's the nerd smiley when you need it)

I guess my other question would be re: the converging ILSs...

Would you hear it on the Arrival ATIS "Converging ILS X and X in use" or would it be something that approach would just expect you to be ready for if they toss it on you?

Thanks again!

-mini

 

[Axel]

Would you hear it on the Arrival ATIS "Converging ILS X and X in use" or would it be something that approach would just expect you to be ready for if they toss it on you?

Yes and no, respectively.

 

[Vector4fun]

Ummm, as far as the Cat I, II, or III stuff, I'll just clear you for the ILS approach. What minimums you're legal and willing to fly to are up to you. Just don't smack the Control Tower...


That said, I wouldn't be surprised that other facilities with different layouts and situations are doing it differently.

 

[minitour]

Thanks again guys

-Cliff (think Cheers) er.....mini

 

[gfvalvo]

Respectfully: You are confusing the converging ILS with the PRM close parallel ILS.

You are correct. I just re-read the appropriate sections in the AIM and cleared up my confusion. Thanks for pointing out my error in such a civil (i.e. non-flaming) manner.