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

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

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).

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).

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.

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..

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

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.

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.

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.

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

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

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.

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

DeanM

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.....

Their respective performance departments would assess it and provide takeoff charts.

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.

Yes they were.

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.

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.

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

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.

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.

The last para of the news item....

"The Australian Transport Safety Bureau says it is collecting information about the incident, and may conduct a formal investigation."

:ok:

To answer some q's

2.5 tonne in 737 is not much. Approx 60 mins. 1 missed approached and recircuit and you're at legal mins.

Bn-ad. Per tonne of fuel carried extra it will use about 60kg. So 5t is 300kg= $350. Does not sound much but virgin do 3000 flights per wk ( from website) = 1 mil/wk. Not all would use 300kg but rough enough.

So it is a find balancing act b/w balancing commercial and safety considerations. Why we get paid the big bucks ;-)

I've been wondering for years what relevance the number has after a PROB fog. It doesn't matter operationally whether it's PROB 10 or PROB 90. If there's any probability of fog or other phenomena reducing the visibility below the alternate criteria, or whatever the exact AIP wording is, you need an alternate.

So why don't we ditch the number entirely and make it just PROB, meaning there is some probability, so gas it up?

Or, even better, remove the term PROB entirely. If there is a chance of deteriorating weather during a certain period just forecast it as such. It makes the TAF/ TTF shorter, which makes it easier to read, and makes no operational change as far as flight crew are concerned.

I just hope that those involved are receiving any support and help that is needed. At the end of the day the souls on board count was the same at the conclusion of the flight as it was when it started, and that is a great thing.

The crew was an experienced one and I'm sure every avenue was exhausted before the final call was made. Sometimes everything can be done right and you can still find yourself pushing the proverbial uphill.

Let's allow the facts to be discovered, and turn this into a situation we can all benefit from.

Kharon:According to Abe Froeman:Perhaps his familiarity with Mildura was a factor? (My recollection may be inaccurate, but wasn’t there an incident about a decade ago during which the captain of an international aircraft inbound to Sydney(??) made a decision to divert to Tamworth(??), which was the aerodrome at which he’d done his training, and had to be practically ‘ordered’ by the on-ground chief pilot to divert to Williamtown(??) due to fuel considerations?

Anyway, the genius of the ATSB’s ‘beyond Reason’ approach will now come to the fore:

Investigation? Done!

Zero systemic issues. Only violations by the PIC.

CASA ‘deals’ with the pilot and everyone’s happy and safe! :ok:

Fuel query
 

Hi all,
I was wondering how pilots calculate fuel with walk on cargo not being weighed.
There was an Aircrash Investigation show on tv last night on that very subject.

Care to elaborate? Never had anything like that in my ten years there.

Absolutely bog standard just about everywhere in Europe, SE Asia, Middle East etc. Trip Fuel + Contingency Fuel + Diversion Fuel + at least 30mins holding fuel at diversion airfield + fuel for an approach and landing, regardless of weather forecast at destination, more may be added, if there is weight/room if fog, TS, BR etc. is forecast. Never go without a diversion and forecast wx. at diversion at ETA must be above Cat 1 minima. If payload too much to allow this then a 're-dispatch' plan may be used, an achievable destination en route is selected but if fuel approaching this destination is sufficient then flight can continue to original scheduled destination, company variations will apply.

At capts. discretion, when approaching one hour to go to destination, which is an airfield with parallel runways, both serviceable, No Sig Wx, and if fuel is dropping below minimum required then the diversion fuel may be used to complete flight to destination, again, company variations apply.

Possibly not in Australia or the USA?

INTER and TEMPOs with PROBs less than 40 may be disregarded for ETOPs alternates at our mob.

With regard to the PROBs:

MANUAL OF METEOROLOGY PART 2 (ISBN 0 644 09903 8) from BOM states, on pg 118, that PROB is defined as "condition whose occurrence is doubtful or uncertain (50 per cent or less)".... So I guess by exclusion, anything else in the aerodrome forecast is only has 50% or greater likelihood of occurring.

IIRC you will only see PROB 30 or 40 on a TAF, no other percentages are used.

Astinapilot
 

Thanks for that info, shows how the numbers add up..

Another one for you, do Captains get reviewed on their decision making re alternate fuel? I'd ask bro but he's well, out there somewhere with loads of "gas"!

Yes. Jetstar have started to do it, graphs of uplift by capt and base.

My last employer has been doing it for years.

Virgin no. We get graphs of where we sit occasionally but no one has questioned me. Problem arises that company has a min legal fuel policy and some guys take this. Most often you want a little more even on nice days. A lot more on not so nice. Virgin carry alternates most places.

When they show the Captains their fuel uplift graph at Jetstar, do they have a big gold star for every time the Captain put on extra gas and then didn't divert because they had the ability to hold for 20mins thus saving the company thousands of dollars and keeping the passengers happy at the same time?
Or do they just say 'Geez Wayne you're in the top 20th percentile for uplift, sort yourself out'.

Metro Man, I know, it was just an example to illustrate the point that it's of no operational relevance whether the probability is 10 or 90%, it still requires the carriage of an alternate or holding. So why not just ditch the number or the term PROB entirely and just forecast it - the operational impact is precisely the same. PROB30 might give you a warm fluffy feeling that it's 70% not likely to happen but is operationally of no relevance.

Generations of regional airline pilots have never trusted inland city/town morning CAVOK forecasts in winter when anti-cyclonic conditions exist with dry bulb, wet bulb temperatures within one degree of each other. A call to the forecaster at Mildura Met. Office equips the pilot with additional knowledge when decision making, a line of defence which I expect is not pursued by modern flight ops. departments. As mentioned previously, good airmanship by the crew in a safe outcome. Perhaps unkind judgement here if events happened too quickly for flight ops. to catch up.

As far as I am aware there is no show and tell with fuel graphs and they know the response they would get if they did. I have never been questioned on my fuel uplift.

In my company a report is required if a diversion takes place due to weather, but no report is required if a diversion is avoided due discretionary fuel.

So, no, the bean counters have no idea how often the pilots save the day.

Here inlies a problem.

I think to simply blame the Met Man or the BOM is overly simplistic. Like most government bodies, they're asked to do more with less. And given less resources to do more with. And one can't just blame Labor or Gillard, as both sides of politics are of the one colour in this regard. :{

To be honest I don't go anywhere without an alternate no matter what the forecast weather. On my wee domestic jet it makes sod all difference to fuel burns to carry the extra. In the past 3 years I have had diversions due to earthquakes on final approach, a student stacking it in on the runway ahead of me and severe turbulence on approach. Do I give a toss what the boss thinks... Not really, I am paid to make that call, the bean counters can worry about the finances. Fact of the matter is I work for an airline that can't justify the purchase or hire of GPU's at each port resulting in regular maintenance burns in excess of 500kgs, it would take me weeks of carrying an extra ton here and there over 30 minute sectors to equal that wastage.