Hi,
I enjoy my 777 PMDG. But i have a little technical question about the Baro or Radio settings to display for the DA when landing.
Imagine we are landing on the EDDK airport, performing the ILS14L approach (Elevation of THR 14L is 230 ')
On the charts we can see this info :

 

ILS Cat II Category D (B777) :  323 (93)

 

What does i set on my MCP :

 

- BARO with 323  ?

- BARO with 93  ?

 

- RADIO with 323  ?

- RADIO with 93   ?

 

Could u give me the answer and the explanation ?

Thanks a lot.

Radio is referred to the height (AGL), as I know, if the visibility is okay for making a normal landing (CAT I), use the Baro setting which is referred to MSL . When the weather condition is bad and low vis CAT II or III, you have to set the DH to Radio

 

 

What does i set on my MCP :

- BARO with 323 ?
- BARO with 93 ?

- RADIO with 323 ?
- RADIO with 93 ?

Could u give me the answer and the explanation ?

 

BARO is height above sea level, as measured by your BAROmetric altimeter (just the regular altimeter, which measures based on barometric pressure).

RADIO is height above ground level, as measured by your RADIO altimeter.

 

You use BARO at any time the chart does not specify "DA" in the minimums section.

You use RADIO at any time the chart specifies "DA" in the minimums section.

 

As such, you'll end up using BARO 99% of the time.  Contrary to popular sim-belief, ILS approaches are actually pretty rare when compared to visual approaches (though many crews are taught to select the ILS approach in the system as a backup to the visual approach, and just in case ATC asks them to "intercept the localizer" to aid the visual approach).  Furthermore, just because the aircraft is capable, and the approach is available, it doesn't mean that the approach will be used.

 

CAT-II and CAT-III approaches are only really pulled out of the hat when required by low ceilings or low visibility.

Contrary to popular sim-belief, ILS approaches are actually pretty rare when compared to visual approaches (though many crews are taught to select the ILS approach in the system as a backup to the visual approach, and just in case ATC asks them to "intercept the localizer" to aid the visual approach).

 

In the US that's true, but not necessarily in the rest of the world. Certainly in the UK you'll normally get an ILS approach.

In the US that's true, but not necessarily in the rest of the world. Certainly in the UK you'll normally get an ILS approach.

 

Really?  I guess that probably makes no sense to me based on how we push traffic.  With CFMU from runway to runway, I'm sure that makes a little more sense for the environment, and making it easier for the computer to process and predict.

 

Still...seems horribly inefficient.

 

...cue the "well EGKK is the busiest single runway in the world" comment. :rolleyes:

I'm certainly no expert in what works and what doesn't. I don't work in the aviation industry so I can only provide what little info I've picked up from random sources and a bit of controlling on VATSIM!

 

Gatwick isn't the best example for cramming aircraft in on the approach; I believe they typically use 6nm separation for arriving aircraft so they can get departures out between them.

 

Heathrow arrivals are down to around 4nm (they use one runway for arrivals, one for departures so no need to fit aircraft in). They have around 2 go-arounds a day, out of ~1,700 aircraft movements (so ~850 arrivals), probably down to controller initiated instruction due to insufficient separation.

 

I seem to remember spacing in the US is indeed a fair bit closer; does that put the onus for separation for arriving traffic in the pilots hands?

 

All interesting stuff anway!

 

 

Gatwick isn't the best example for cramming aircraft in on the approach; I believe they typically use 6nm separation for arriving aircraft so they can get departures out between them.

 

haha - there's always someone who points out that Gatwick is the busiest single runway airport whenever pushing traffic and efficiency come up.  It was partially my way of staving off the commentary, because what I said could've been taken as slightly critical of the CFMU approach.

 

 

 

I seem to remember spacing in the US is indeed a fair bit closer; does that put the onus for separation for arriving traffic in the pilots hands?

 

Our generic numbers are 3nm in the TRACON, 5 up at the ARTCCs (though the intention is to get that down to 3 with ADS-B at some point).

 

Those numbers can go lower in certain cases (notably LOAs between operators and the facility).  Additionally, the controller may solicit the traffic to the pilot.  If the pilot reports the traffic in sight, the onus of separation is then transferred to the pilot, and radar separation requirements are essentially nullified.

 

As such, over here, it makes a ton of sense when you want to pack aircraft into an airport.  Separation can be reduced down to pilot discretion.

 

Here's a pic of MTV (area of Potomac Approach feeding DCA) on a typical night, and this isn't even pushing it:

OK, thanks

So in this case, BARO with 323 displayed.

 

 

Really?  I guess that probably makes no sense to me based on how we push traffic.

 

Well - relieving separation control of IFR traffic and assigning multiple landing clearances for one runway makes very little sense to Europeans

Well - relieving separation control of IFR traffic and assigning multiple landing clearances for one runway makes very little sense to Europeans

 

haha - see, that makes no sense, though:

"Hey yeah, you've got traffic at 12, 5 miles, same altitude, same direction."

"Got him!"

"Okay, good to know.  Glad you saw him.  I'll now continue providing the same positive separation as if you couldn't see the traffic.  Useful, traffic call, eh?  We're still going to delay your approach because I need to keep IFR separation even when you're in visual conditions and reference."

 

The multiple landing clearances is something I've already discussed ad nauseum, but anticipated separation really isn't a foreign or unsafe concept.

I'm not saying it's inteherently unsafe - but it is a foreing concept to me

gillesdenice, on 27 Nov 2013 - 04:50 AM, said:

OK, thanks

So in this case, BARO with 323 displayed.

it seems you have an answer ... despite the off topic drift (again) of our learned friends !

 

i haven't seen the EDDK chart.

 

with radio, its use is often "problematic" if as is in many approaches, the height agl a mile or so from touchdown can be many feet different from the height there & then above the threshold .... eg an approach over water to a runway 30' above the water body !! if it is used for cat 3 for example, it is often supported by data about the approaches profile agl.

 

but having said that baro is as accurate as the local qnh & your settings !

Additionally, the controller may solicit the traffic to the pilot.  If the pilot reports the traffic

So, never report traffic in sight.  :lol:

with radio, its use is often "problematic" if as is in many approaches, the height agl a mile or so from touchdown can be many feet different from the height there & then above the threshold .... eg an approach over water to a runway 30' above the water body !! if it is used for cat 3 for example, it is often supported by data about the approaches profile agl.

 

It's not problematic, it's precisely the reason why RADIO mins aren't used for CATI approaches. A CATIII approach will have mins 50ft or less, at which point you're already passed the body of water/buildings/anything else that might give a reading other that hight AGL, and be over the threshold.

Heathrow arrivals are down to around 4nm

 

In normal operations we work to the wake turbulance minima so generally down to 3nm (medium followed by medium or anything bigger).  If there is a bit of a headwind and the weather allows it we reduce this to 2.5 mile spacing.  With the catchup from 4 miles it's not unusual for the first to be touching down and the 2nd within 2 miles from touchdown.

 

 

 

They have around 2 go-arounds a day, out of ~1,700 aircraft movements

I believe our stats average out to 1 go-around a day over the course of the year.  Obviously you may go 4/5 days with non and then on a bad weather day have 4 or 5 in a row.