Ask The Pilot

[jb747]

From reading that fb thread (and ignoring most of it) it sounds like EK standard procedure is maximum 2 missed approaches followed by a divert. Which suggests they would always carry the fuel to do that, I guess?

I expect most airlines have at least a suggestion with regard to how many missed approaches you do. Ours is not a hard ruling...there are too many variables to make it so. I wouldn't read to much into how much fuel EK had. Coming from NZ is only a short flight, so carriage of a bit of fuel is simple. Their longer flights would be every bit as restricted as ours. As often as not, the diversion airports people are carrying are literally just down the road. Beyond that, there was nothing nasty in the Melbourne forecast, and what was there was almost certainly going to be a short term event. I wonder how much fuel they had when they got to Sydney? Unlikely to be much.

 

[Quickstatus]

Flex TO causes the power settings to mimic TO performance as though it's a hotter day??. Therefore causing TO performance to be reduced. So the pilots tell the FMC to assume a higher ambient temperature?.
Are there any other ways TO performance is derated (apart from manual)

how much influence does Ground effect have in worsening TO performance?. Is this a significant factor in marginal conditions?
Did the calculations for the QF32 landing take GEffect into consideration?

 

[flychrisfly]

100%...reduced by the temperature. About 88% at 45ºC.

The above quote is in reference to TakeOff power. I had always assumed that the power required for an increased temperature also increased since the air was less dense and therefore supported less lift => more thrust. Is this not the case?

 

[jb747]

Flex TO causes the power settings to mimic TO performance as though it's a hotter day??. So the pilots tell the FMC to assume a higher ambient temperature?.
Are there any other ways TO performance is derated (apart from manual).

That's basically it...though I'd hate to see a real 72ºC day!

There's also a series of fixed derates, which we don't use.
D04 96%
D08 92%
D12 88%
D16 84%
D20 80%
D24 76%

Can large airliners use the Ground Effect in any beneficial way - eg in a missed approach or TO?

Not really...it's what makes you float on landing.

 

[jb747]

The above quote is in reference to TakeOff power. I had always assumed that the power required for an increased temperature also increased since the air was less dense and therefore supported less lift => more thrust. Is this not the case?

The power required may increase, but the ability of the engine to produce it is reduced. As gets hotter, they simply make less thrust.

 

[QF WP]

Some interesting commentary here from some armchair experts... https://www.facebook.com/AIRLINESECRETS/posts/1877248892548120:0

As I said in a previous thread, I don't think I would have diverted. But, I also have the luxury of sitting in my office. I didn't see the conditions they saw (and I expect it was pretty solid shear). The choice they took was safe. Everyone got where they were going, albeit a little later. The aircraft is in one piece.

When you can do it you can be a critic. Until then....

From reading that fb thread (and ignoring most of it) it sounds like EK standard procedure is maximum 2 missed approaches followed by a divert. Which suggests they would always carry the fuel to do that, I guess?

The one comment that appears to be pretty close to the best answer is from a SIM Instructor at MEL:

Alexander McAllister I was at YMML at the time and the ATIS was reporting low level wind shear as a trough was passing through. Winds above 1500ft were 340/15kts, however winds below 1500ft were reported as 180/15kts. Wind at ground level at the time was 360/8kts. The aircraft carried out a missed approach from rwy34, did an about-face and tried an approach to rwy16 before carrying out a second missed approach and diversion. Given the carrier's recent bad experiences with wind shear I can understand why they're being more cautious...

 

[jb747]

Roster time again.

Leftover from the current roster:
24/02 MEL-LAX 93
25/02 LAX-MEL 94

03/03 MEL-LAX 93
04/03 LAX-MEL 94

New roster:
17/03 MEL-LAX 93
18/03 LAX-MEL 94

27/03 MEL-LAX 93
28/03 LAX-MEL 94

09/04 MEL-DXB 9
13/04 DXB-LHR 1
15/04 LHR-DXB 10
17/04 DXB-MEL 10

24/04 MEL-DXB 9
28/04 DXB-LHR 1
30/04 LHR-DXB 10
05/05 DXB-MEL 10

 

[petercr]

Is there any reason why they wouldn't have diverted the EK flight to ADL (where I'm sure they'd have a fuel tab seeing as hey have other regular flights in) or to AVV (or was that too close)? Surely one of these two would have made more sense for a 'splash n dash'?

 

[jb747]

Is there any reason why they wouldn't have diverted the EK flight to ADL (where I'm sure they'd have a fuel tab seeing as hey have other regular flights in)

I don't think they run 380s to Adelaide, so they'd have limited support. Most likely a headwind on the way there, so possibly more fuel required. Adelaide also has a curfew, and I expect they figured an overnight was quite possible. Sydney will almost certainly handle that better (in terms of accommodation, crewing, etc) - (though I could be wrong, I haven't flown to Adelaide for about 15 years).

...or to AVV (or was that too close)? Surely one of these two would have made more sense for a 'splash n dash'?

I expect that Avalon is only available to them as an emergency field. You might get a splash there, but there will not be any dash to it. Yes you can go there, but all sorts of issues. Whilst we use it as an alternate to some flights, it's what I call a paper alternate. It only exists to make the approach to Melbourne legal. You really don't want to go there.

 

[clazman]

No chance.

I guess this response to the camera is more pilots dont want to be filmed over operational reasons?

 

[harvyk]

I expect that Avalon is only available to them as an emergency field. You might get a splash there, but there will not be any dash to it. Yes you can go there, but all sorts of issues. Whilst we use it as an alternate to some flights, it's what I call a paper alternate. It only exists to make the approach to Melbourne legal. You really don't want to go there.

Which other airports in Australia would you consider paper alternatives? Also do you consider them paper alternatives only for the A380, or would you have considered them as paper alternatives in the B747 / B767 as well?

 

[jb747]

We're probably a long way from getting aboard a pilotless airliner, but what are the thoughts of real pilots on this development. Thin edge of the wedge? A dangerous novelty?

It will happen one day, but I doubt that I'll be alive to see it. No pilot has total faith in any maker's systems. To expect that they'll think of everything, is a very long way from the state of the art.

As for the Dubai thing....I'll believe it when I see it.

 

[jb747]

Which other airports in Australia would you consider paper alternatives? Also do you consider them paper alternatives only for the A380, or would you have considered them as paper alternatives in the B747 / B767 as well?

Any place where there's a runway, but no real support. Learmonth, Kalgoolie, Derby. Alice Springs. Avalon. Tindal. Canberra, Williamtown. It varies for every type. Many of the places I've mentioned are destinations for smaller company aircraft. Many are not available for the 380 at all.

 

[jb747]

How much influence does Ground effect have in worsening TO performance?. Is this a significant factor in marginal conditions?

I've never heard it mentioned with regard to take off.

Did the calculations for the QF32 landing take GEffect into consideration?

The calculations were irrelevant. The program choked anyway, so its output wasn't realistic. You have to land. Singapore was the longest runway. So land. If you overrun, then that's the way it is. Sometimes you simply have to wear whatever happens.

 

[jb747]

Sydney ATIS from about 1715 Saturday. Anyone see any issues?

INFO J. TMP: 23. WIND: 150/20 XW 20 KTS, DW MAX 5 KTS, RWY 07. EXP ILS OR GLS APCH. RWY 07 FOR ARRS, RWYS 16L&R FOR DEPS. DAMP. VIS: 8 KM.

 

[mannej]

Sydney ATIS from about 1715 Saturday. Anyone see any issues?

INFO J. TMP: 23. WIND: 150/20 XW 20 KTS, DW MAX 5 KTS, RWY 07. EXP ILS OR GLS APCH. RWY 07 FOR ARRS, RWYS 16L&R FOR DEPS. DAMP. VIS: 8 KM.

Cross wind and damp runway?

 

[petercr]

Sydney ATIS from about 1715 Saturday. Anyone see any issues?

INFO J. TMP: 23. WIND: 150/20 XW 20 KTS, DW MAX 5 KTS, RWY 07. EXP ILS OR GLS APCH. RWY 07 FOR ARRS, RWYS 16L&R FOR DEPS. DAMP. VIS: 8 KM.

Outbound traffic is going to have to cross incoming traffic at either take-off or taxying speeds?

 

[jb747]

All passed by now...

Sydney was in the process of having a bunch of thunderstorms pass through. They were passing from the northwest...which means I'm surprised at the wind direction, and would expect a rapid shift in direction for any aircraft departing. The upshot could have been quite similar to what forced the EK diversion from Melbourne the other day.

 

[Awesom Andy]

WIND: 150/20 XW 20 KTS, DW MAX 5 KTS, RWY 07. EXP ILS OR GLS APCH. RWY 07 FOR ARRS, RWYS 16L&R FOR DEPS. DAMP. VIS: 8 KM.

With such winds, realistically, how many pilots would actually attempt (or accept) a take off from the 16L/R?

 

[Quickstatus]

Sydney ATIS from about 1715 Saturday. Anyone see any issues?

INFO J. TMP: 23. WIND: 150/20 XW 20 KTS, DW MAX 5 KTS, RWY 07. EXP ILS OR GLS APCH. RWY 07 FOR ARRS, RWYS 16L&R FOR DEPS. DAMP. VIS: 8 KM.

Mode14a operations at Sydney airport

http://www.airservicesaustralia.com/wp-content/uploads/LTOP_Mode14A.
http://www.airservicesaustralia.com...ways-at-Sydney-Airport-to-share-the-noise.pdf


Is XW20 and DW5 the maximum allowed wind conditions for dry runway as per airservices australia?
http://www.airservicesaustralia.com/wp-content/uploads/12-139FAC_NCIS-Runway-selection_P2.pdf

Interestingly the ATIS does not suggest the wind conditions are gusty
What if the actual wind conditions are gusty, XW>20 DW>5. What happens then?