BA088 Mayday
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Ha ha ha ha ha!
Hang on whilst I pick myself up off the floor. How often do you operate into Heathrow? The place is scheduled at 98% of capacity; it'll be a miracle if this didn't cause SOME delay.
.4
Ha ha ha ha ha!
Hang on whilst I pick myself up off the floor. How often do you operate into Heathrow? The place is scheduled at 98% of capacity; it'll be a miracle if this didn't cause SOME delay.
.4
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Perhaps that was unkind - I apologise.
If there wasn't any other traffic about I doubt he would have overflown Heathrow on his way to Luton, he would have just gone straight in. The fact that he elected to start that indicates there must have been traffic around to get delayed.
.4
If there wasn't any other traffic about I doubt he would have overflown Heathrow on his way to Luton, he would have just gone straight in. The fact that he elected to start that indicates there must have been traffic around to get delayed.
.4
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Correct me if I am wrong but I believe that FARS require that the full 5% contingency, (or is it 10%, can't remember), of A from departure airport be carried as opposed to 5% of A from an en route airport.
Hence fewer US aircraft arriving at destination short on fuel.
Hence fewer US aircraft arriving at destination short on fuel.
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FAR 121.646 add 5% fuel for 'engine deteroriation', add 5% to forecast wind speed or add 5% fuel if forecast wind not measurable according to FAA standard. In addition to hold and diversion requirements.
I dont know of any airline that flight plans 20mins of holding fuel into any london airport
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ETOPS - I think 'ep' means "I dont know of any airline company flight plan system that flight plans 20mins of holding fuel into any london airport"? I'm with you.
EP
Could you clarify that? It only costs the operator money when it's burnt, not when it's loaded into the aircraft, in reality. For the accountants, strictly speaking, it goes into "stocks".
If it's not used, the next uplift is that much less. It it is used, it was possibly needed to avoid a diversion.
My point being that if an airline does not plan 20 mins hold fuel, it may not be due to the beancounters.
I don't think that this would change much if you take variable fuel prices, additional weight etc into account, although a real expert may rise up to shoot me down about that.
I dont know of any airline that flight plans 20mins of holding fuel into any london airport.
It's recomended by the CAA, but that falls on deaf ears with oil prices through the roof.
It's recomended by the CAA, but that falls on deaf ears with oil prices through the roof.
If it's not used, the next uplift is that much less. It it is used, it was possibly needed to avoid a diversion.
My point being that if an airline does not plan 20 mins hold fuel, it may not be due to the beancounters.
I don't think that this would change much if you take variable fuel prices, additional weight etc into account, although a real expert may rise up to shoot me down about that.
Last edited by old,not bold; 10th Nov 2007 at 09:17.
Could you clarify that? It only costs the operator money when it's burnt, not when it's loaded into the aircraft, in reality. For the accountants, strictly speaking, it goes into "stocks".
the more you carry, the heavier the aircraft, therefore the more fuel used.
These incidents of 'fuel emergencies' are pretty rare into the London TMA, IMHO the system works well at the moment.
the more you carry, the heavier the aircraft, therefore the more fuel used.
To quote an example; how much additional fuel is burnt to carry the fuel needed for a 20 mins hold at FL100 by a B777 operating a 3,500nm sector into LHR? And how much by a B737 on a 850nm sector into LHR? Does anyone know the answer?
If that 20 mins extra fuel means losing revenue payload then of course there's a real cost IF revenue is actually lost as a result (ie operating at 100% LF), but how often is that the case?
Last edited by old,not bold; 10th Nov 2007 at 10:20.
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I dont know of any airline that flight plans 20mins of holding fuel into any london airport.
It's recomended by the CAA, but that falls on deaf ears with oil prices through the roof.
It's recomended by the CAA, but that falls on deaf ears with oil prices through the roof.
I think 'ep' means "I dont know of any airline company flight plan system that flight plans 20mins of holding fuel into any london airport"? I'm with you.
Lets face facts here.
It doesn't matter what the price of the fuel is, it is either carry what is reasonably required, or divert.
Some companies choose to limit fuel uplift to the absolute bare minimum, others use a more reasoned approach...or at least many of their Commanders do.
It is, however, interesting to note that in the last few years, it is British carriers that have come up short.
No surprise there.
I rather suspect that if it was a foreign carrier, the UKCAA would have just a slightly closer look.
Nothing like having the home regulatory authority in your pocket.
Warning Toxic!
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To quote an example; how much additional fuel is burnt to carry the fuel needed for a 20 mins hold at FL100 by a B777 operating a 3,500nm sector into LHR? And how much by a B737 on a 850nm sector into LHR? Does anyone know the answer?
However- you want that fuel at the end of the flight, so of that fuel, you are burning 4%/hr during the flight to end up with that much at the end of the flight. Not sure of 777 figures- (say 7000 kgs/hr? Guess- 747 is about 10,000kgs/hr). So for 7000/3 (ie 20 minutes) kgs remaining end of flight, 7000/3 (=2,333) x 4% x 8hrs= 750kgs, so you would need to load 2333+750=3100 kgs of fuel to end up with 2333 kgs for your 20 minutes holding. If you don't believe that, try working the other way reducing 3100 by 3%/hr for 8 hours.
Pretty solid figures established by experience. This is why that '20 minutes' at the end of the flight is not popular with accountants. Statistically- once in a while you can expect occasional minor fuel emergencies. However the record of aviation is just about right- how many airliners have dropped out of the sky without fuel due to current fuel rules?
A lot of the 20 minutes fuel can be made by unused contingency fuel plus anticipated savings from being able to exclude your diversion (ie commit to destination) assuming certain criteria are followed.
*411A- not going to get suckered in on that fishing lure you floated! I think 20 minutes holding on every flight into the UK is bizarrely extravagant on a valuable resource. It is not flight planned, and rarely ever used. It is as safe to not carry it as long as your decision making process is brought forward and you take a divert decision earlier. That is the key point- thousands of flights can carry less fuel, but the point must be accepted that occasionally one or two flights will divert because they did not carry the extra fuel. Then you do a sum- is it cheaper to carry 20 minutes extra fuel for all flights, or accept that with less fuel, there are extra diversions (actually incredibly small in number). Remember, we're talking about probably a broad average of 750kgs per every 777 flight fuel burnt just to carry enough fuel to maybe delay or avoid the once in a blue moon diversion? The accountants tell us....don't carry unnecessary fuel- it's cheaper to accept a small number of diversions. That's good enough for me. Safety is not affected. The extra fuel just means you can hold longer- you can still have a crisis if you do not take action, you just have longer to play with before the crisis. It's a cost/benefit thing.
In my experience, extra fuel still often does you no good. Through having round trip fuel last month, I was able to hold for nearly 2 hours waiting for fog to clear, at 2000kgs/hr. It still didn't work- the fog didn't, although I thought there was a good chance. I would have been better off diverting that much quicker. So what good did that extra 4000kgs achieve? Nothing.
Last edited by Rainboe; 10th Nov 2007 at 11:29.
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There's lots of interesting stuff being mentioned here with regard to how much gas we're planning to arrive at destination with, but the fact of the matter is, that we don't have access to the 'crystal ball' or 'twenty-twenty hindsight' whilst at the planning stage prior to departure. It's my belief that it's the 'experience' and good judgement by the commander that will win the day.
You have only to experience a few departures from the US Eastern Seaboard and inbound for an early arrival slot into LHR to become acquainted with the issues in hand. You will certainly expect a minimum of twenty minutes holding. A departure from JFK will most certainly mean that you will be taxying for up to one hour prior to departure. The opposite can also happen... some years ago pushing back from Philly we actually taxiied straight to the departure runway, so we were airborne within fifteen minutes of pushing back (and not the expected one hour!). Having got airborne and looked at the FMS arrival time we found ourselves to be one hour early; plus the fact that slack tailwinds were in fact not true, but a fifty knot tail component... great news; but not really, because we were now well within the approach ban time prior to 6.00am. 'Company' wouldn't allow us to arrive early and, although we had the extra fuel on board, we couldn't hold for the one hour, so we were directed to land at Shannon for a refuel and go; therefore arriving into LHR approximately forty-five minutes later than our scheduled arrival time. Deterioration of the Shannon weather from being CAVOK to a howling crosswind right on the B747 limits didn't make life any easier... during the landing (still in the dark and lashing with rain) the No.2 engine reverse surged and pushed out a huge plume of flame; witnessed by a newspaper reporter sat in the aft of the aeroplane, who got straight onto his mobile to report the incident directly to his newsdesk! The news was immediately reported on UK TV 'breaking news' of a B747 landing in flames after a transatlantic crossing... the company chairman witnessed the news whilst he was having breakfast at home! As you can perhaps well imagine, all hell broke loose within company headquaters... the moral of the story is; even with the extra gas on board, it won't guarantee you having a nice day! Missinformation, either by a computer screen or a 'nurd' sat in seat-row 49A trying to get a news scoop, won't be discounted until the actual story is released by those in the know... even on PPrune by all accounts! The Irish authorities kept us in Shannon for the day/night whilst the incident was investigated... we 'blacked' the runway; not withstanding the fact that the wind increased in force to warrant the closure of the airport for a few hours! As for the crew... just a routine day at the office. The Guinness was fabulous!
TCF
You have only to experience a few departures from the US Eastern Seaboard and inbound for an early arrival slot into LHR to become acquainted with the issues in hand. You will certainly expect a minimum of twenty minutes holding. A departure from JFK will most certainly mean that you will be taxying for up to one hour prior to departure. The opposite can also happen... some years ago pushing back from Philly we actually taxiied straight to the departure runway, so we were airborne within fifteen minutes of pushing back (and not the expected one hour!). Having got airborne and looked at the FMS arrival time we found ourselves to be one hour early; plus the fact that slack tailwinds were in fact not true, but a fifty knot tail component... great news; but not really, because we were now well within the approach ban time prior to 6.00am. 'Company' wouldn't allow us to arrive early and, although we had the extra fuel on board, we couldn't hold for the one hour, so we were directed to land at Shannon for a refuel and go; therefore arriving into LHR approximately forty-five minutes later than our scheduled arrival time. Deterioration of the Shannon weather from being CAVOK to a howling crosswind right on the B747 limits didn't make life any easier... during the landing (still in the dark and lashing with rain) the No.2 engine reverse surged and pushed out a huge plume of flame; witnessed by a newspaper reporter sat in the aft of the aeroplane, who got straight onto his mobile to report the incident directly to his newsdesk! The news was immediately reported on UK TV 'breaking news' of a B747 landing in flames after a transatlantic crossing... the company chairman witnessed the news whilst he was having breakfast at home! As you can perhaps well imagine, all hell broke loose within company headquaters... the moral of the story is; even with the extra gas on board, it won't guarantee you having a nice day! Missinformation, either by a computer screen or a 'nurd' sat in seat-row 49A trying to get a news scoop, won't be discounted until the actual story is released by those in the know... even on PPrune by all accounts! The Irish authorities kept us in Shannon for the day/night whilst the incident was investigated... we 'blacked' the runway; not withstanding the fact that the wind increased in force to warrant the closure of the airport for a few hours! As for the crew... just a routine day at the office. The Guinness was fabulous!
TCF
Rainboe, The first para in your post certainly makes the quantified case for NOT carrying the additional fuel as a matter of routine, at least on long haul flights. You are the expert who's shot me down!
I simply cannot get my mind around how the arithmetic works for short haul, but then again I'm not aware if short haul flights can get delayed at LHR in quite the same way that long haul ones apparently can be.
I simply cannot get my mind around how the arithmetic works for short haul, but then again I'm not aware if short haul flights can get delayed at LHR in quite the same way that long haul ones apparently can be.
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I simply cannot get my mind around how the arithmetic works for short haul, but then again I'm not aware if short haul flights can get delayed at LHR in quite the same way that long haul ones apparently can be.
The only, perhaps avoidable, penalty LH get is when they pitch up before the end of the night jet ban, are not exempt and so and have to wait till 06.02 before landing. It's not unusual to have traffic arriving from 05.30 and then holding for 20 to 25 minutes.
Given the number of a/c that can land before 06.00 it's nothing more than a political sop that makes us continue with the 06.00 restriction. The 06.00 to 07.00 hour is then needlessly busy with lost of crossing tracks on base/final approach with knackered pilots and atcos working their socks off as ATC try to get back to no delays for the start of the 07.00 to 08.00 hour. Totally stupid imo.
Note: individual a/c of any type may, at any time, move slightly up or down the queue inbound as ATC look for the most efficient landing order down the approach, but time gained or lost is only a few minutes.