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Anthony Carn
7th Jan 2003, 11:34
Another thread touched upon a recent case at LHR , where some problems were possibly caused to some inbound pilots due to a runway closure, leading to holding. The basic question raised was, "Why should a few minutes' holding cause distress ?"

My usual fuel load (max 1000nm, usually much less) :

Taxi
Departure take-off to destination landing
5% of departure t/o to destination l/d, with a minimum cut-off
30 mins holding at destination holding waypoint, low level
Destination go-around to alternate landing
30 mins holding at alternate holding waypoint, low level

Extra added on for all the usual reasons -- notams, weather, icing, lower levels, serviceability, airmanship, common sense, past experience etc. etc. etc. etc. etc. .


Anyone agree/disagree. I never stop learning, or wanting to.

Would also be interested in the long-haul side of things, of which I've no experience, asuming there's any difference (apart from more zeros at the end of the figures).

Fright Level
7th Jan 2003, 12:38
You misread my other post. I did not say pilots were having problems, I said they were in discussion with the company about possible diversion.

You carry 30 mins more fuel than I do, as I usually plan;

Route burn
Contingency (% or ERA)
Diversion
Reserve (30mins)
Taxi

Now, as the reserve is the legal minimum, then the only fuel carried "spare" is the contingency, planned remaining is therefore the reserve plus unused contingency. Reserve fuel is not considered "holding fuel at alternate" or anything else other than what *must* be in the tanks on landing.

There is no problem adding extra fuel if the ETA is a busy time at the destination and vectoring/holding can reasonably be expected, or CAT3 conditions are forecast or any one of a number or reasons left to the pilot's discretion but we don't regularly carry holding fuel we don't use, that's one of the things the contigency fuel is for.

Arriving at destination holding fix with all the contigency and (commercial alternate) diversion fuel available, it makes sense to talk to the company and see where they might like us to go when ATC announce, without notice, a runway closure that indicates landing with the contigency all used up in a 25 minute hold.

To always carry another 30 minutes of fuel around is commercial madness, it is surely better to suffer the odd (rare) fuel diversion than to burn fuel carrying the stuff around?

ETOPS
7th Jan 2003, 13:09
The trick is always to be comfortable with your decisions. I fully accept that simply adding an arbitary amount "for the wife & kids" on each and every sector is commercial madness, but when the situation requires extra then, by all means, take it.

As an example: Winter weather blankets Western Europe. Fog and snow almost everywhere. Flight planned fuel from MAN to AMS was 7000kg using Boeing 737-200 equipment. I actually took over 15 tonnes as my evaluation was that it was unlikely we would get in either at AMS or the alternate DUS. Ops were insistant that as we were CAT 3 we should depart on schedule so off we went. A few hours later back at MAN we landed with under 3000kg left having been all around the Netherlands and Germany as visibilities dropped to 50m. The only two major airports were left MAN & PWK.
Throught all this I was able to take my time making decisions as fuel was not a problem and things were working out much as I presumed. An extreme example I know but as they say "I learned about flying that day"

Anthony Carn
7th Jan 2003, 13:13
Apologies to the Moderators for posting in RP. Good job I had enough diversion bytes in my tanks to make it to TL !

EDDNR -- was referring to BOAC's post, not that it matters -- it simply sparked of the idea of this separate thread which might be of interest.


Thanks for your comments, though. In my case, contingency, even if I had all of it unburnt at start of destination hold, would typically be, say, 150 kg. That's 4mins 30secs of destination holding at the stipulated 1500ft ; not a lot, then. I frequently get "10mins holding" estimates into LHR, which often work out that way, so I'd frequently be off to my alternate !

In addition, when everyone else is diverting from LHR, the alternates can fill up and/or become congested very quickly ; I've been in that scenario! I remember diverting to LTN one time and parking virtually where I'd turned off the runway -- chocka ! Alternate holding becomes highly likely in those cases, too. If you divert on min fuel and have to hold at alternate, then you're declaring an emergency, are'nt you ? (less than final reserve on landing).

BOAC
7th Jan 2003, 14:34
AC - for me, and I think, most, the '30 mins holding at destination' (planned as a matter of course) is an expensive luxury!

"EDDNR -- was referring to BOAC's post, not that it matters"

I'm not hurt, really ;). My point was that there should be no cries of 'foul' if you have to hold for 20 minutes inbound LON major airfields. That indeed is the required fuel planning the CAA ask for/expect? If you reduce below that holding fuel at LON you do it at your own risk and will suffer more 'stress' eg if a runway closure happens. The CAA recommendation is, as I recall, to build EXPECTED holding into route fuel. Then 'contingency' that. Then comes fuel for mum and the kids if you wish it/have them.

In 37 years of aviation I have been SERIOUSLY let down by the Met (world-wide) service at least 4 times, landing (non commercial) with empty tanks once, getting past PNR (commercial light twin) with destination wx well below minima once, finding the whole of the south of UK's airfields bar one in unforecast freezing fog (commercial - thank you Manston!) and almost having to either land a Harrier in Stavanger high street - or eject - once. I have grey hairs. I do not want any more (grey ones!).

Fright Level
7th Jan 2003, 14:37
Which all goes back to my original point about long hauls being caught out yesterday. Weather forecast CAVOK or pretty close to, nothing in the NOTAMS, middle of the afternoon lull at LHR (which is probably why they decided to carry out the de-ice/pre-ice then).

ATC only learn about delays at our TOD and the situation builds as we are the last 100 miles into LAM.

If there are sudden holds announced with 10, then 20 then 25 mins being quoted, isn't it sensible to discuss options before you use up the contigency?

Wish I worked for a company where it was considered OK to carry an hours holding fuel on every flight.

Your decision on your MAN 737 day was correct with all the information you had to hand. Yesterday was an exception.

411A
7th Jan 2003, 15:24
Many long-haul flights operate on re-dispatch, where the company has this procedure.
Have only had a problem at LHR one time....holding at LOGAN for 20 minutes, suspected a rat when told to hold for another twenty (ATIS all the while reporting 4000 metres), asked the F/E to monitor LHR ground and he reported that the airfield was going to low vis procedures and the RVR was now 800 metres....ATIS still reporting 4000.
Quick dash to LGW, first one in with others following close behind.
Three tons remaining at shutdown (TriStar), slim but workable.

ATC very accomodating that day...:rolleyes:

puddle-jumper
7th Jan 2003, 15:26
To always carry another 30 minutes of fuel around is commercial madness, it is surely better to suffer the odd (rare) fuel diversion than to burn fuel carrying the stuff around?"

Really ? How much does it really cost to carry that extra 30 mins of fuel compared to the odd (rare) diversion. Our quotes are aprox. 50 kilo's extra burn per extra 1000 K carried per hour. 50 kilo's is around 62 litre's, last I heard Jet A1 was around 15p per litre, ( don't know the latest figure though ). So, total cost for carrying an extra ton per hour = £9.30. Our average flight is about 1 hour 30 mins so aprox. £14 per flight.
Now this may not sound allot but to be fair you have to multiply by the total flights per year - for me at the most = 450. Total cost per year = Aprox. £6300

Anyone care to work out how much a divert cost ? It's not just the extra financial cost of going to another airport and either doing an extra flight to final destination or coaching pax. from one to another, it's also the delay it incurs and the damage to customer relations - particularly when the competition has got in because they can hold at destination. The problem is the accountants can not easily put a price on that, unlike adding up the cost of carrying fuel.

I may be wrong but I'll stick with my 'commercial madness' and do what I always do - take at least an extra 20 mins fuel if I can get it on, it keeps me young if nothing else. :D

Fright Level
7th Jan 2003, 16:41
My original post referred to long haul flying. Over the sectors I fly, half the extra fuel would be burnt carrying it, meaning having to load say 10 tonnes extra to arrive with 5,000kg (lasting 30 mins on my type).

With many long haul departures up to MTOW, that means we'd need to leave 100 pax or 10 tonnes of freight behind just to carry fuel "just in case". Commercial madness, as I said.

Anthony Carn
7th Jan 2003, 17:50
There are two distinct types of operation being discussed in parallel here, which is causing some of the disagreement.

1 -- Long haul. Carrying extra fuel creates a vicious circle. To carry fuel increases fuel burn to the extent that it becomes necessary to carry even more fuel to compensate and restricts pax/cargo loads. Cost escalates rapidly.

2 -- Short haul. Carrying extra fuel is usually a relatively minor problem with respect to pax/cargo and cost. Frequent sectors and business style pax demand low diversion frequencies as a high priority.


Make sense ? :cool:


PS. -- BOAC, no offence intended. I did'nt mean that your post did'nt matter, I meant that it did'nt matter that EDDNR thought that I was referring to his post ........ if you see what I mean. ;)

BOAC
7th Jan 2003, 20:38
"2 -- Short haul. Carrying extra fuel is usually a relatively minor problem with respect to pax/cargo and cost. Frequent sectors and business style pax demand low diversion frequencies as a high priority."

I could not agree more. Try costing the goodwill of the pax who have missed their connections/meetings/etc. and are now sitting somewhere else, unable to get off and waiting for the 'plan' to come together to get them to where they paid to go in the first place! Sometimes though, as has been said already, it is better to scoot off early and refuel 'first in the queue' if you cannot wait.

PS AC - No offence taken - all in "the best POSSIBLE taste" as KE? used to say. I was only 'joshing'!

FlapsOne
7th Jan 2003, 22:46
UK CAA strongly reccommend 20 mins extra holding fuel for flights inbound to the London TMA.

It's in an AIC.

I'll fish out the reference if anyone's interested.

Nugget90
8th Jan 2003, 08:30
For interest and as a reference, you might like to read/revisit the CAA's report on UK air operators' fuel planning policies. This report, which was based upon information obtained in the Summer of 2000, describes JAR-OPS 1 fuel policy and how various operators specified these requirements for the aeroplanes they operated. In particular, the report addresses reserve fuel.

The report can be accessed through www.chirp.co.uk>>confidential reports>>library.

Pontius' Pilot
8th Jan 2003, 14:06
Our company includes the 20 min hold at LHR in every SITA. Makes it a lot more stress free after a 12 hour flight to have this available, as on the day in question.

seat 0A
8th Jan 2003, 14:54
FlpasOne,

I`d be interested in your AIC.
At our company we typically depart for LHR with trip fuel, altn fuel (EGSS mostly), final reserve(30 min), and a statistical amount of contingency fuel, which has a minimum of 5 min.
Now, this contingency fuel will in some cases be more than 20 min (as it is statistical), but more often it is closer to 10 min.

Regards.

FlapsOne
8th Jan 2003, 18:00
seat OA

The reference is at www.ais.org.uk

You need to register (free for change!)

AIC 36(P170)/98 entitled 'Fuel reserves for aircraft approaching the UK'

It's a .pdf file that I can't cut and paste from.

In essence it re-iterates the JAR fuel policy minima but goes to say that the London TMA is a bit of a special case because the 'no delay expected' of 20 mins quite often applies.

It goes on to point out that a diversion accross the TMA will probably not be a straight line.

The clear recommendation is not to arrive in the London TMA with the JAR legal minimum fuel - ie: have that 20 mins 'in the bank (tank?)

Have a read and make your own judgement.

Rgds

TopBunk
9th Jan 2003, 14:36
All

I keep statistics (sad maybe, I know), that I review in order to quantify probabilities.

In the last 9 months or so that I have kept stats, I have operated into LHR about 200 times for a large operator using shorthaul aircraft - ie fairly representative of an LHR user.

Now I'm not saying that I carry flight plan fuel by any means - far from it - but in those 200 rotations I have on only 8 occasions used more than trip + contingency fuel (15 mins), and on those occasions the most I have used above contingency was still only about 80% of my diversion fuel, in fact on only 2 occasions have I had to commit (the last time yesterday evening on a flight from a near European destination) as I usually plan to cover statistical holding at the 15% level from extra fuel.

LHR never fails however in it's capacity to catch you out, about 3 weeks ago, mid afternoon, 30 mins holding out of the blue in CAVOK esaterlies (18th Dec2002) and again yesterday evening - ok snow in am but lovely evening, but ground delays with no stands causing reduced flow rates inbound = 40 mins holding - very glad the ZFW was down 5 tonnes and I loaded 200 kg extra fuel!

Safe flying out there!

411A
9th Jan 2003, 20:55
Interesting that TopBunk mentions "commit".
Does this mean that some British operators decide unto themselves that they can use their designated alternate fuel, on a more or less routine basis, to commit to landing at LHR?
What happens if LHR suddenly closes, for whatever reason?
Do they land in the Thames?:rolleyes:

Where I have worked, diversion is REQUIRED if down to alternate fuel reserves.

Fuzzy Duck
9th Jan 2003, 22:03
My Company Ops Manual while not actually defining 'contingency fuel' describes it as compensating for:

-deviations of an individual a/c from expected fuel consumption data
-deviations from forecast met conditions
-deviations from planned routeings/cruising FLs.

No mention of holding. As I understand it, if I consider it likely that I will have to go into the hold on arrival I need to consider taking extra fuel and leave the contingency element out of the calculation completely.

FlapsOne
9th Jan 2003, 22:32
I think JAR OPS defines contingency. It's exactly as you describe.

The key element here is that contingency fuel is there in case something UNFORSEEN happens en route (different route, level etc).

Now if something is forseen, the CAA interpretation of likely holding in the London TMA for example, you should not plan to use contingency fuel for that purpose.

The decision to go below min fuel required to approach, go round and divert with 30 mins hold (Company Min Reserve or similar) is a difficult one but, of course, can happen.

Don't forget, there's no guarantee that your alternate will not close suddenly as well - but there are only so many contingencies you can reasonably plan for.

In the end, that's what we're paid for.

TopBunk
10th Jan 2003, 07:13
411A

My company's CAA approved fuel policy under JAROPS allows a flight to continue to destination with calculations showing less than reserve + diversion fuel remaining at destination, for example, so long as max delay known or EAT (expected approach time) received as long as landing assured (*) and possible to land with at least reserve fuel remaining.

At any time, if it becomes apparent that you MAY land with less than reserve fuel, then a PAN is called, and if you WILL land with less than reserve then a MAYDAY call is required.

(*) Landing assured means taking into account any forecast weather changes and aircraft system degradation plausible.

Imagine a scenario, you are holding with 1 hour of fuel on board close to an airfield with 2 runways (say LHR) with a received EAT in 15 minutes + 10 minutes for the approach, so can reasonably predict landing with 35 minutes fuel, the weather is stable with a 400ft cloudbase and 1000 metres vis, is it not better to continue to hold than to divert to somewhere with just one runway, which may be a 15 minute flight away where the weather is the same, where you would then land with 45 minutes fuel at best?

Food for thought?

seat 0A
10th Jan 2003, 07:21
411A

That doesn`t sound too smart, now does it?
If you are down to altn fuel and you divert from LHR to, say EGSS, you would end up being committed to that field. Where there`s only one runway, nobody`s expecting you, you`re not familiar with the field etc etc.
My company does allow to commit to destination, as long as you land with at least 45 min fuel. The considerations to take into account when coming to this decision are left to the commander.
How about that for common sense eh?

411A
10th Jan 2003, 15:39
Quite simple really...when down to alternate + reserves fuel, divert.

Seat 0A,

Not familiar with the alternate? Well, as PIC you certainly should be, 'tis a company requirement where i've worked.
Alternate doesn't know you're enroute?
That is what ATC is for....:rolleyes:

And especially for the long haul folks, to overfly a suitable enroute alternate KNOWING that you will be really short upon arrival at destimation is, in my opinion, a terminating offence...as in, find another job.

TopBunk
10th Jan 2003, 19:36
411A

Quote <Quite simple really...when down to alternate + reserves fuel, divert>

Wrong --- It's about making command decisions armed with all the knowledge that comes from all sources available and at all times never prejudicing safety. That means that if everything is legal and sensible then commiting to your destination is both permissible and sensible from both commercial and safety viewpoints.

As has been said, diverting from a multi runway airport with fully functioning nav aids and with reasonable weather to an alternate with a single runway and similar weather when you have been passed an estimated approach time and will land with at least reserve fuel is not the best decision.

What is your problem with that logic, exactly?

FlapsOne
10th Jan 2003, 22:32
411A

I would only divert in the circumstances you describe IF

the destination airfield could not give me an EAT due to unknown delays - blocked runway for example
or
the EAT was too long to wait (happened to me last week)

Going to an alternate say 20 mins away, when you have an EAT in 10 mins or so, puts you in a far worse position on arrival at the alternate then you would have when approaching destination at the EAT.

You could well have enough in the tanks for another go if it all goes pear-shaped!

As for long haul over-flying alternates knowingthey will be short on arrival - there's a bit more to think about I reckon.

411A
11th Jan 2003, 00:45
TopBunk.
The answer to your last question is...legality, plain and simple, considering FAA requirements. May be permissable under JAR.
That would be your problem.

FlapsOne

Just for the sake of discussion...
Why would you, assuming you were the Commander of a longhaul flight from (for example) KUL inbound for LHR, overfly suitable enroute alternates KNOWING you would have too little fuel upon arrival to divert, never mind hold?

In companies where I have worked, the Chief Pilot would take a very dim view of such proceedings, and with good reason, IMO.

Green Guard
11th Jan 2003, 01:44
Hm,
shall I say it again ?

The ONLY correct BLOCK fuel calculated before DEPARTURE
is the one that eventually results
in 30 min of fuel AFTER LANDING.!




(on any airport)

FlapsOne
11th Jan 2003, 17:46
411A

Read the last line of my post again!

However for discussion purposes, in the circumstances YOU describe, I would divert and pick up the extra gas.

In the circumstances I described, I wouldn't.

ergo:

There is no standard answer to this problem. There comes a time when the best decision must be made given the circumstances at the time. I get paid to make that decision and justify it, if necessary, afterwards.

TopBunk
11th Jan 2003, 18:06
411a

Are you telling me that FAA regs require you say inbound to LAX with 4 runways in good wx conditions with an EAT known, that at all times you must preserve div fuel, and that you are not allowed under the regs to proceed to your destination, but must when it gets to the point that div fuel is about to be used that you MUST divert to a (possibly) single runway airfield (where there may be delays, and the wx may be worse) and MUST reject the possiblility of making an approach to your destination?

If so, not much joined up thinking there, is there?

Under the old UK CAA and now JAROPS the system works as previously described, it's not "my PROBLEM", it's my/our regulatory framework, which would appear to allow the captain greater flexibility on the day to decide on a course of action (whilst retaining the responsibility for any decisions, to be justified later if necessary).

411A
12th Jan 2003, 01:44
TopBunk

Not in the regulations, but in the operations specifications issued by the FAA to all aircarriers. Therefore, if specified therein, crews must divert unless the alternate is below landing minima, or forecast to be so at time of arrival. If the long range flight is operating under re-release, a different alternate (or two) may be specified in the re-release dispatch message.

To be caught short is not good, as Avianca has found out.
QF and MH have had rather close calls at LHR as I recall....ie: little fuel left in tanks at the parking bay.:eek:

TopBunk
12th Jan 2003, 07:04
411a

Thanks.

No one here is suggesting doing anything that contravenes any regulations, be they implemented by the authority or by the company, so you must do what is required of you, sensible or otherwise.

It would appear that in the UK/Europe we operate with slightly greater flexibility at the hard end of the flight (it doesn't really matter if you're shorthaul or longhaul as the decision making process is the same) when it comes how the remaining fuel is used.

As to Avianca (into JFK), that they ran out of fuel was compounded by their poor communications with ATC as to the fuel remaining. As to QF and MH into LHR I don't know the fuel in tanks they had, but I presume that they require a minimum of 30 mins AT TOUCHDOWN, they may end up with less on stand (you can wait quite a while for a stand at LHR). So they could have landed with 30mins and arrived on gate with less. Furthermore the BA engineers at LHR will raise an Air Safety Report if you end up on stand with less than 30 mins fuel at max landing weight (which could of course differ from the reserve fuel requirements on the day). It is often the engineers ASR's that find their way into the press.

In all of this, lets not forget that while if would be (never been there myself) very uncomfortable landing with less than 30 mins fuel, it is still fuel that is usable for the day that the best plans don't quite work out.

411A
12th Jan 2003, 19:28
TopBunk,

Unless of course...if the tank ports are ah...uncovered in the process, due to (for example) body angle.

Watched this personally many years ago with a B707 in Singapore (Bangladesh Biman), the results were not pretty.:(

Altho this particular incident was on departure (would you believe) ...:eek: good grief:eek: :eek:

wilsr
12th Jan 2003, 21:55
Discussion on fuel is usually about situation of poor forecast wx.
The more dangerous situation, IMO, is the scenario of CAVOK, peak period and a sudden airfield/ATC shutdown - forcing perhaps 30 or 40 a/c (all of whom planned on minimum delays) to suddenly have to look for a nest somewhere close.
Present "political" situation certainly doesn't make this scenario any less likely.