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-   -   Virgin Aircraft 'Emergency' Landing (https://www.pprune.org/australia-new-zealand-pacific/517250-virgin-aircraft-emergency-landing.html)

triathlon 19th Jun 2013 01:55

My understanding is probs are only forecast at 30 or 40.

ruddman 19th Jun 2013 01:58


I too got caught out yesterday, and I would have landed with 2.5 tons of fuel. I think the met boys were having a bad day, as the fog wasn't forecast and didn't clear until 1-2 hours AFTER the forecast TTF period! A quick discussion with my FO and we just went back to where we had just come from. The good news on that one was that the wind @ FL350 was 260/176kts, so picked up a nice little tail wind! I have left the auto-pilot on many times doing a practice RNAV/Z runway approach, and had made the decision a long time before, that it would get you within the runway confines, in fog. You may take out a few lights, but way better than crashing in a paddock!! I don't know the facts, but I imagine this is exactly what the Virgin crew did. Maybe the QF crew were just alerting them to the actual viz conditions as they made their final approach. I too would have prepared the cabin for a possible crash landing as they have had a lot of rain up that way, and the grass verges would be very soft. Brilliant result i reckon!

Non-pilot question if that's ok. I thought that was pretty typical for a 737, landing with around 2.5t?

skkm 19th Jun 2013 02:14


My understanding is probs are only forecast at 30 or 40.
Correct.
AIP GEN 3.5 3.6.7

(Although, in my observation, PROB30 seems a more or less definite guarantee that there is going to be fog).

waren9 19th Jun 2013 02:19

So far this this winter, we have had
1. Jets autolanding below ILS minimas
2. Jets landing below NPA minima (I presume)
3. Jets diverting to non company airports when a fairly common (if irregular) winter weather phenomenon occurs

All with no fuel for other options.

How is this worlds best practice?

Some aspects as to the nature of that phenomenon is quite well known. i.e its onset, severity and duration can be quite hard to predict.

We as a pilot group in this age are ever more constrained by rules and manuals that are only getting fatter and fatter.

Personal judgement and discretion is slowly becoming a thing of the past as newer guys are coming through are only shown/taught to play by the manual. Fuel load is becoming more and more surreptitiously limited by payload through company policy.

Time to take a step back guys before something gets bent.

Just because a manual or a rule book says it might be OK, we need to ask ourselves more and more, just as much as Teresa Green and his mates would have done in the past "**** the forecast, is my fuel load a prudent one?"

Dont leave it to BOM, a company manual or a CASA reg to keep you out of trouble. The guys that write that stuff have different drivers and KPI's which are often at direct odds with our own aims (Not talking about BOM here).

Mr Whippy 19th Jun 2013 02:36

Apparantly in South African Airways its policy to always carry an alternate unless the destination has multiple useable non-intersecting runways, or at any other time the crew feels it necessary, no questions asked. Seems pretty sensible to me.

Ramjager 19th Jun 2013 02:38

If BOM hasnt tried to kill you at least once you havnt been flying long enough.
Accuracy or lack there of in Aussie forceasts is or from my experience pretty common.
If you are basing fuel decisions relying totally on accuracy of forecasts you are setting yourself up. How many times to forecasts change post departure and if you are basing your fuel uplift on a trans con flight from Bris to Per do they really know what the weather will be in 6 hiurs time? Jeez they cant even get what it will be like in 3 hours time!
To expect 100% accuracy is im sorry never ever going to happen.
My questions would be and i havnt seen it posted did Mildura have a prob of fog of fog on the TAF?
Was there a TTF which superseded it without fog on it?
Having diverted several times while operating into Tassie due unforecast fog in Slowbart the first thing on my diversion checklist is W..does my diversion field have an acceptable forecast that makes it Legal to divert there.
As frequently Launy may have a prob of fog ruling it out as an option as to divert there then have it roll in as what happened yesterday means you have insufficient to return to Melbs so its straight back to Melbs you go Cavok or not at Launy.
On company fuel policies since when does that ever obligate a Captain to carry less fuel than they see fit you are protected under the Regs every day to carry as much as you feel you require..
The guys did well to get it down just live to know what he forecasts said..

ejectx3 19th Jun 2013 02:40

As spelling nazi said, if your loins are stirring, fill her up shags!

Matt48 19th Jun 2013 02:57

Speaking of fuel reserves.
 
Hi all,
Would anyone have an idea of how much fuel a 777 APU would use in 4 hrs waiting on taxiway for a storm to clear.
Would it have much effect on reserve fuel for a flight from O'Hare to LAX.
I was once in this situation as a pax, just wondering.
Thanks, M48.

Icarus2001 19th Jun 2013 03:08

Boring I know but I will wait for the investigation to publish a report.

As far as BOM forecast accuracy, they get it right much more regularly than getting it wrong, only some of you guys seem to forget that. Sure, getting it wrong has implications such as we see here but that is why the PIC makes the final call about fuel load, not BOM. I am always amazed HOW accurate BOM get winds aloft and cloud base etc.

Ultimately, a safe outcome with some lessons for all, and cheap too.

FYSTI 19th Jun 2013 03:14

Firstly, hats off to both crews, great job to get everyone on the ground safely given the sh!t sandwich you found yourselves eating.

This incident confirms us as being in the ranks of the aviation third world , and has all the hallmarks of similar incidents for example the 2010 Polish Air Force crash in Russia, which didn't have a "good outcome".

Thankfully both aircraft were 800's with high accuracy nav systems. It could well have been a different outcome with a steam driven non-GPS model.

triathlon 19th Jun 2013 03:18

Surely airlines can find other ways to save money without having min fuel policies if it compromises safety.

ejectx3 19th Jun 2013 03:22

Yeah.... Half the number of "managers" , and fire the boss.

flynerd 19th Jun 2013 03:27

BOM Forecasting Accuracy
 
One of the problems with BOM and Ozzie Govt spending cutbacks is that there are less local experienced people doing the forecasting.

A lot of present day forecasting is done relying only on historic data modelling and statistics. So, they _will_ get it right more often than not - that's how statistics work! :8 :8

But when some conditions "outside-the-box" are looming, they will get it wrong as they need LOCAL experience and a window to look out-of to make reasoned forecasts.

Another factor is that the local BOM may not be "local". For Adelaide, they could be outsourced to Sydney, Canberra or Melbourne (or Mumbai). Now that cannot help.

deanm 19th Jun 2013 03:35

I'm guessing that neither airline would attempt to takeoff from Mildura with diverted passengers on board?

DeanM

Octane 19th Jun 2013 03:46

Just asked my bro if he went to Mildura recently. His reply "Nope.. don't carry company fuel, always have lots of gas. Keeps my life simple...!" :}

What I don't really get that is, if say you always carry say an extra 5T of fuel for mum, is that extra weight going to really be a huge expense in the scheme of things. As a passenger I'd rather pay an extra $2 fuel surcharge (a complete scam anyway) than endure go arounds in fog at night with no fuel for an alternate.

What would be the actual dollar cost of carting an extra 5T of fuel Brissy to Adelaide be anyway?

To the uninitiated the entire situation seems absurd.....

Lookleft 19th Jun 2013 03:54


I'm guessing that neither airline would attempt to takeoff from Mildura with diverted passengers on board?
Their respective performance departments would assess it and provide takeoff charts.


One of the problems with BOM and Ozzie Govt spending cutbacks is that there are less local experienced people doing the forecasting.
That explains an awful lot about the state of forecasting in this country. If this is indeed a "bad fog season" then it is even more important for the BOM to be more conservative with their forecasting. For them to miss the fog in Adl is unfortunate but to then also miss it for Mildura is borderline incompetent.

Well done to the crew. I can't imagine the thoughts going through their mind when they realized that they would have to do an improvised autoland with a chance of it not being successful.

I'm also interested to know if the airport authorities activated their emergency plans and if the landing had not been successful, if emergency vehicles were at the airport.

ejectx3 19th Jun 2013 05:03

Yes they were.

Kharon 19th Jun 2013 05:07

N.B. I hereby formally acknowledge that this is only my idle wondering; I was not present, don't have enough data and I am only speculating "over a coffee", while waiting for 'the report' to appear; provided booze, bad living and old age don't cart me off first.


TW # 81 "Has anyone ever seen anything higher than PROB30 for FG".
I've never checked this out; but, a wise old pelican (Met man at Sydney) told me one day when I was jumping up and down about the 'bloody forecast', "we only need to within plus or minus 70% of actual, to be within our required accuracy boundaries". So, 30% prob +70 =100% correct if forecast right; or conversely >60% right, if forecast wrong. - Just saying. - Tricky stuff this fog, clear sky, light breeze, Dp and OAT close and closing, high pressure, winter, early morning at a known fog factory near you. The met office computer model might not 'see' it, but I betcha the 'locals' know.

But was Mildura not a passing strange choice though?; Brisvegas to Adelaide track, (round numbers, broad brush) from dim memory (Venel is it ?) was about 210 nms from Adelaide. From there it's 275 ish to Adelaide and it's "about" 260 nms to Melbourne, well before TOD anyway, lets say, for sake of argument 35 minutes out, 15 before TOD. Plenty of options from there. Even from o' head YMIA it's only what? 250 nms to Melbourne as opposed to 180 odd nms to Adelaide. That's only + 70 odd miles, which, in a 73 series anything, is not too long a stretch. The Adelaide met data does show the trend toward fog, so I am left, still wondering, why risk Mildura, provided Melbourne was readily available? But then again, I wonder about a lot of things, mostly about the same things Capt. Claret was (#64), back up the page there a bit.


SN – "But we had bucketload so was a no brainier to wait it out."
Tim Tam to that man, for a pure definition of no sweat aviating. The met data I've seen provided and this time of the year, would have me reaching for "the books" and a sharp pencil. Q) Why have you always got 4 tons fuel on board landing Bloggs?. (A) 'Cos I can't get any more in the little bugger, that's why......:D

Lookleft 19th Jun 2013 05:17


The met data does show the trend toward fog
It does eventually but if you look at the 2130 SPECI with MIFG they then state NOSIG which is supposed to be a statement of trend for the next 3 hours even though leading up to it the temp and the dew point are 05/05.

At 2200 the penny finally drops and they start trending FG.

Forecasts should be just that and not akin to Monday morning football discussion.

VC9 19th Jun 2013 05:27

It is possible to get caught out whether you have minimum fuel or lots of fuel. With minimum fuel the decision is clear cut, in this case autoland at an ILS equipped airport, which in hind sight may have been the safest option.

The fact is that all major capital city airports should have at least one CAT 3 capable runway. It is 2013 not 1963.


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