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BmPilot21
3rd May 2002, 21:16
If we take sector (minimum) fuel on my 737, which includes 7 mins (150kg) taxi, and then taxi for 15 mins, can I legally depart? I have a 5% contingency of fuel, for unexpected delays, but is this for airborne use only?

I'm assuming I legally need my diversion, so I can't bin that, plus we're full, so a burn correction woouldn't solve it either.

basil fawlty
3rd May 2002, 21:33
When your taxi fuel allowance is burned off (1000kg in our case on a 74) then any extra is eating into your contingency yes. At airports with long taxi times we put on an extra allowance and this is added into the total contingency fuel on the paperwork. Its up to the P1 to decide if hes happy to fly with less than the planned contingency fuel if some has been burnt off during a prolonged taxi. Its legal to use contingency yes, but is it wise? well thats a different matter.

Edited to actually answer you question!

TheMagus
3rd May 2002, 21:49
Your Operations Manual may say something different but...

JAR-OPS requires you to have at least the final reserve fuel left when you land, everything else may be consumed.
If at any time, when airborne, you find yourself with less than the final reserve fuel you have to declare an emergency.
In other words the regulations allow you to use the contigency fuel.

I assume that your minimum sector fuel includes final reserve fuel.

BmPilot21
3rd May 2002, 22:16
Thanks for your replies,

We do always try and take extra for taxi if its expected. Also, we will usually have more than sector fuel to allow for delays etc. Even if we do take sector fuel, we are not usually full, so we could make a burn correction to give us a lower required fuel.

Themagus:
Yes, min. fuel is
pre-flt + trip + contingency + alternate + final.

I agree you must land with not less than final reserve fuel, but you cannot plan to do that at your destination (ie bin the alternate) unless certain conditions apply (EAT issued, and can land with worst f/cast weather plus single failure of equipment (eg. downgrade from cat iii to cat i etc.)) Therefore, you must plan to arrive at the initial holding fix with alt. fuel intact until you know the EAT etc.

Also, alternate fuel must be carried unless performance precludes it + VMC etc. My point is that it would certainly be illegal to burn into anything other than cont. fuel at the holding point, and CAA guidelines state:

"Because at the planning stage, not all factors which could have an influence on fuel consumption to the destination aerodrome can be forseem, cont. fuel is carried to compensate for such items as:

1.Deviations of an individual a/c from the expected fuel consumption.

2. Deviations from f/cast met conditions

3, Deviations from planned routing / crz alts".

All of these are once airborne, so I wasn't sure whether cont. fuel could be used on the ground. Taking it a step back then, could contingency fuel not also be used for extra APU burn for an unexpected slot or start up delay on stand? At what stage are you allowed to start using cont. fuel? Pushback?

basil fawlty
4th May 2002, 10:17
Trip fuel is for the trip A to B, diversion fuel to get you to your alternate B to C, everything else except minimum fuel in tanks and initial taxi fuel is put together as a contingency figure. In actual fact, our taxi fuel is taxi/APU fuel and the same rules apply. i.e prolonged APU ops using up the taxi/APU fuel allowance, before T/O will result in using some of your contingency.

BEagle
4th May 2002, 18:37
Interesting. Quite often we have to take off on long-haul trips without 5% contingency for the whole planned flight - but with ample contingency for an en-route alternate. We then keep a very close eye on the fuel state until we reach the point at which, hopefully having burnt nothing more than anticipated, we now have sufficient fuel for the remainder of the flight to the original destination plus 5% contingency plus alternate fuel allowance - if we haven't, then we have to divert to the alternate. This is fine for an appropriate long-haul operator - but if I was flying for a corner-cutting low-cost I'd be very concerned at eating into my revenue-driven meagre reserves so early in the trip as when taxiing to the departure RW holding position!

Stan Woolley
4th May 2002, 19:41
BEagle

Your smug and pompous negative attitude towards everything civvie is bad enough but I really take offence at your comment about 'corner-cutting low cost'! For a start its obvious that you know to$$-all about the civvie world because you're clinging to your VC10 like a bloody limpet.

I happen to fly for EZY and I can assure you that the fuel I carry is anything but corner cutting. For a comparison however I suggest you read the thread in ATC called MOR'd-Ouch,which gives some insight into how much BA (don't) carry.

I have met a lot of ex RAF people in the airline world and as a general rule the ones that actually did some impressive things tend to be the most modest and display an attitude the exact opposite of your own!

BEagle
4th May 2002, 21:27
Flanker - I don't quite understand why you feel obliged to react in such a vitriolic manner. As I'm sure you're aware, the CAA issued Pink 170 after a number of dangerously low fuel occurences - the message is there for all to note.

Incidentally, I most certainly do not have any specifically negative attitude 'towards anything civvie' - and yes, I certainly do enjoy the variety of military aviation. And I sincerely hope that I'm never a passenger in any civil aeroplane whose pilots have to do 'pretty impressive things'........

Have you seen the April 2002 'Feedback'? There's a most interesting article about 'a growing tendency observed primarily with some of the 'low cost' operators, of flight crew reacting inappropriately to air traffic clearances and instructions received' . Clearly some people are giving your market sector a bad name - I'm not for a moment suggesting that it's your particular airline - and that is something which does give me cause for concern because I share airspace with them. Neither do I like flying with airlines who are working to such tight margins that they have to offload 176 kg of catering on a flight from STN-FRA - even with a significant tailwind at altitude.

My 'long haul' comment was to reflect that mathematically there is a significantly better chance of recovering to 5% contingency for the balance of the flight as the flight progresses - because the effect of a taxiing time delay will lessen the longer the total flight time. 10 minutes in 1 hour is significant - whereas in 8 hours it probably isn't.

Stan Woolley
5th May 2002, 00:09
BEagle

I replied in such a vitriolic manner because you are one of the people'giving your market sector a bad name' by putting 'corner cutting' and 'low cost' together, and using phrases like 'revenue-driven meagre reserves'!It just pi$$ed me off.

What has the Pink 170 AIC got to do with being a low cost operation? I believe it was aimed more at the long haul operations into London than at anyone else.The chirp thing is not good news I agree but I have to say I am not personally aware of this problem.

We are all JAR operators and as such are required to carry legal minimum fuel, there are people who are happy to do just that, but they are in the minority. I agree it seems unusual to have to offload one hundred odd kilos of catering on such a short flight, but who knows why? artificially limited TOW's, runway restrictions at STN/FRA, fuel strike at FRA, tech problems,weather etc.I know of 767's offloading catering/water to get the fuel on (not on a FRA flight admittedly:) )

From experience I rarely carry the bare minimum plog fuel so that academic discussions such as this thread remain just that- academic.

It's very easy to multiply fifty kilos saved by two thousand flights a year or whatever but it is much more difficult to quantify all the times a bit extra onboard saved a diversion or a return to stand or whatever, keeping the program on time and saving a monumental cock up.

And I'm sorry but many of your posts do come across as pompous, to me at least. I actually said 'some impressive things', meaning career wise-as in one example being synchro lead in the red arrows, not taking the roof off a car with a Jaguar type of impressive!!

BEagle
5th May 2002, 00:46
They never did explain why they needed to offload the weight of the catering - I know for a fact that it wasn't down to any of the reasons you mention as possibilities on that particular day! Personally I think that 'someone' didn't NB the strong tailwinds prevailing which could probably have meant being too heavy on arrival?

On the 'how much fuel to carry' thing, I agree that it is a fine art. Personally I advise people to check the min theoretical computer flight plan value and the maximum fuel possible for the leg (whether limited by MTOW or MLW), the resulting load being somewhere between these two extremes - but to be able to justify their final decision rather than just blowing the shareholders' pennies (your and my taxes) by loading far more than necessary or risking a diversion by loading too little. But if they can't depart with 5% contingency for the planned leg, then they must know the rules for reduced-contingency operation rather than just hoping for the best!

Speaking to someone high up in your company's management last year, the topic of the very short turn round times pursued by another low-cost was brought up. "There are limits", I was told, "We may be cheap, but we're not nasty....!"

DFC
6th May 2002, 15:20
To get back to the original question, IMHO, one can never use the contingency fuel unless it is the very last few drops in the tank before final fuel reserve.

The reason for this is that one can never know with certainty when a contingency situation will occur and you might find yourself eating into final fuel reserve earlier than expected.

To knowingly use up any of the contingency say during taxi means that there is nothing left to allow for any further unplanned poor level or speed restriction or extended routing. Thus the aircraft becomes airborne with less than the required planned fuel.

JAR OPS is clear on what contingency fuel is. It is to compensate for unknown unavoidable errors. I can't ever see a situation where I can sit at the holding point and guarantee 100% that I will not need contingency fuel on this flight.

DFC

greyfox
6th May 2002, 21:57
The simplistic answer to this question is "Planning". JAR requires certain rules for planning, be it Preflight or Inflight.
If these rules are satisfied at the planning stage, then once the aircraft is "in flight" (after 1st engine is started -see MEL) if, as a result of an inflight fuel check, the expected fuel on arrival at the destination is less than alternate plus final fuel reserves, the PIC must take into account the traffic and operational conditions prevailing at the destination airdrome, at the alrenate and along the diversion route, when deciding to proceed to the destination airdrome or to divert, so as to land with not less than finall reserve fuel.
So theoretically and in reality you may use all your contingency,and alternate fuel at the holding point of departure.
The decision is yours!
Call it what you may, "comfort factor", "options" enroute, destination has 2 seperate runways the benefit of which you did not make use of in your "Planning" etc, these ultimately decide what you the commander will elect to do.
These rules allow you to make considered decisions dependent on the facts not restrictions that give a theoretical safety benefit as was in former times when the plan always (well almost) had to conform to the the reality - and vice versa of course- and on occasions intermediate landings had to be made to satisfy what in effect was a planning rule and the commander was not able to make sensible judgements without perhaps bending or breaking the rules.
;)

autoflight
7th May 2002, 01:40
One day a court [perhaps in Athens] may need to decide on the use of contingency before take-off. If they find plane spotters guilty of espionage, or put you away for years because you over-ran the runway on landing, imagine your chances. Greece is not the only country where you might unreasonably suffer.
It is clear enough to me that when you commence the take-off roll, there must be sufficient contingency fuel to destination or an suitable enroute re-planning airfield. Sometimes I have assessed the likely taxi fuel to be many times the standard allowance. Where this will affect max landing weight, I have adjusted planned trip fuel on the load sheet to show legal landing weight. When the actual taxi out fuel is less than expected, and landing weight would be a problem, the actual trip fuel is adjusted by higher speed or lower altitude cruise. I have never needed to reduce payload for additional taxi out fuel, but this could result is a disagreement with my airline. However, regardless of resultant career difficulties, captain must sometimes make difficult decisions. Correct decisions are more important than paying the home mortgage.

FlapsOne
7th May 2002, 12:30
This bit is about as straightforward as fuel planning ever gets.

As contingency is for 'unfoseen', matters.............................

You can quite legitimately use contingency fuel at the holding point before take off IF you did not REASONABLY EXPECT to have an extended delay.

Take LGW in August at peak times for eg: and the wise pilot should reasonably EXPECT extra holding prior to departure and load fuel accordingly (a 40 min gap from gate to take off is not too uncommon) - therefore saving that bit extra fuel for the 'unknown' en-route.

av8er
7th May 2002, 23:41
I agree with flaps one and grey fox, except that our MEL states that we have despatched when we move under our own power (JAR Operator). Seems to me if you get held at the hold point its just the same as getting held at 5000 ft on departure and if things get tight later you need to sound a little more concerned when you tell ATC you need a better level/route etc...!

Slasher
8th May 2002, 05:12
Strictley-speaking contingency fuel is an airborne reserve. Its not meant for contingencys on the ground.

Since contingency fuel is a variable reserve its possible to replan your fuel at the holding point if the reserve amount as stipulated on your flight plan is burnt. You can play around with cruising levels, LRC, (and a CI of zero if FMC-equipped). You can also examine a PNR for enroute diversion. 5% only on those legs is required before take-off. You can also nominate an enroute airfield as initial destination for the purposes of pre-departure fuel legalitys, and designate your intended destination as your alternate as long as met conditions at these places permit. Also a closer alternate to your destination (but outside the minimum distance specifyed in your Co fuel policy) can be nominated (wx permitting) than the one specifyed on the plan. Depending on sector lengths, using these methods can knock off as much as 150kg off your flight-planned contingency.

Once the mains leave the ground the whole game changes and becomes more practical. Your alternate field can be "just over the road" from your destination (again wx permitting). With enroute re-calculations over certain fixes, 5% of B-C is what your trying to protect. This can bring your required enroute contingency down to as low as 60kg (on paper!) one hour out from destination.

PS Im not too familiar with JAR mandatory carriage of contingency reserve but I dont think Im too far off the mark.

GMS
8th May 2002, 09:19
BmPilot21,

In your initial posting you mention you have 5% contingency. I take it you are aware of the other methods allowed under JAR OPS to calculate the fuel requirements for a flight, such as using an ERA and 3% contingency, or using a Decision Point Procedure that requires only 5% from the DP to destination.

If you feel uneasy about going below your 5% from a legal point of view, both these methods will require less fuel, although on a short flight this may not be the case. Many airlines stipulate a minimum figure for contingency fuel. At my airline the minimum for a 757 is 300 kgs regardless of what method you use.

Slasher
8th May 2002, 09:24
Yes the DPP was the method I was trying to remember not the PNR.

HectorusRex
8th May 2002, 09:48
To add my tuppence worth the following maybe of some help.

It may be legal to depart with the necessary minimums on-board, but is it necessarily the action of a prudent pilot?

I was recently the Air Show Safety Officer at a local display, and there was a fuel related incident which concerned a visiting military display team who arrived with a 7 ship formation.
A discussion ensued between myself and the team leader who was requiring a "downwind, reduced length take off due to low fuel state"
The obvious solution was a "top-up" prior to commencing their display, but the oppportunity to do so was declined.
Eventually the team of 6 taxied out to hold full length into wind, and then following a call of "Bingo fuel" from one member, the team returned to dispersal and refuelled!
VERY red faces all round for the team, and which has prompted a request for official clarification of minimum fuel requirements for military aircraft, when involved in civilian operations.

Quoted from the relevant report.

"As a result of a change of decision by some members of the xxxx flying contingent, which resulted in the return of the “xxx xxxxxx” team to the apron for a refuel, it highlighted that there exists a fundamental difference in fuel policy between what is laid down in CAA Rules for civil aircraft, and what is policy for military flying.
There would appear to be a contradiction between the risks to others of a civil aircraft fuel related accident, or the same accident befalling a military aircraft.
It would seem wise to ensure that in non-essential military operations which include such tasks as Civil Air Show participation, that the same fuel requirements apply to all participants.
As an aside, the delay caused by the return for a refuel caused a major delay to both the Air Show timing, and also an in-flight problem to a holding xxxx C-130 which was also in a low fuel state, and awaiting the display team's departure, to carry out a formation parachute display drop."

Definitely not the actions of a "prudent pilot" and BEagle may care to ponder on "Military wisdom"
HectorusRex:confused:

Stan Woolley
8th May 2002, 10:46
I fly for a JAR operator and our ops manual confirms that 'Contingency fuel may be used any time after commencement of flight; i.e. after the aircraft first moves under its own power.'

200kgs min.

BEagle
8th May 2002, 21:25
HectorusRex - whoever that bunch of unprofessional people were, they were NOT exhibiting the degree of flight safety one should reasonably expect of any military display team. I don't support their actions in any way - except for the ultimate decision NOT to take-off!

HectorusRex
9th May 2002, 00:00
BEagle,
Thanks for the agreement!
I gave them 1 out of 10 for Airmanship, and they only got 1 because of the decision to return.
HectorusRex:)

DouglasDigby
9th May 2002, 18:35
Whilst it doesn't give exact guidance for the circumstances being discussed, there is lots of useful information at

http://www.caa.co.uk/docs/50/SRG_FOPS_Fuel_SOC_Focus1.pdf

I would suggest that if the prolonged taxy time is a regular event, then the guidance should be to increase the fuel load to take this into account. Similarly, how many fuel plans ALWAYS use the longest STAR/SID?

fms146
12th May 2002, 12:39
BmPilot21
You have raised a very good question to which the answer is very clear in the JAR-OPS Fuel Policy.

Most of the replies to your post are close to the answer but no one has hit the nail on the head..so to speak..

Total fuel required =

A. Taxi Fuel
B. Trip Fuel...(Starts at T/OFF) JAR Definition
C. Contingency Fuel
D. Alternate Fuel
E. Final Reserve Fuel
F. Additional fuel for operational reasons.

So you can see that the JAR-OPS regulations clearly make the distinction between TAXI FUEL and TRIP FUEL. Since the CONTINGENCY fuel is based on the Trip fuel you must have this at the commencement of the take off as this is,again by JAR definition,when you start using your trip fuel.

So lets now put it all in the real world. I get to work and collect my Ploggs for the trip. After considering all operational requirements lets say I agree with the fuel figures given in A to E above but decide to take extra fuel in accordance with F.

Everyone is happy and we taxi for departure..Has our flight started? For the purpose of logging flight time it has however by JAR definition we have not started using our trip fuel.

We are now delayed and join the que waiting for departure and I realize that we are in danger of using all our Taxi fuel allowance. The only fuel that I am allowed to eat into is the Fuel I have allowed at F above. That is the additional fuel I took on for operational reasons.

Our company operations manual states that we will use the 5% of trip fuel option in calculating the contingency fuel required however if your ops manual allows you could replan the contingency fuel based on 3% of trip fuel and nominate an enroute alternate which may give you some breathing space.

To sum it all up then you must commence the take off with your contingency fuel in tact...

The company operations manual is your bible and obviously you must conduct your operations in accordance with this document. However if you are asking the question in regard to the JAR - OPS regulations then I feel confident I have given you the right answer. Room for thought

Stan Woolley
12th May 2002, 16:47
fms146

The answer I gave earlier is a direct quote from our ops manual, at least the part in inverted commas.

You may interpret it differently but I'm afraid the (JAR) ops manual seems very clear to me.

Capt. Crosswind
22nd May 2002, 03:42
Some points to consider:
Flight plan fuel required should be added to
* Actual taxy fuel predicted from your experience,not a "company standard" figure.
* Unusable fuel
* Dip stick/ gauge allowable error.
* You only sweat a low fuel state once
and
bear in mind that in the scramble for the alternate when a
busy destination closes you never get the flight level your diversion fuel was based on.

AGODIA
24th May 2002, 20:09
Bmpilot21

The way I see all this is no matter if you are legal or not, if you are NOT HAPPY with it.
Thanks good in my airline the only thing I will not worry about when any things get bad is FUEL, I´m what other gays say low-cost-cutting-corners airliner BUT FUEL.
Besides the fuel cost at the moment aren´t so high to be really concerned in being so precise with fuel calculations.
And the most important thing I´m HAPPY.
I remember a Chief pilot in another airline saying Blas.. about not to carry extra fuel ...... till he had to divert becouse unexpected weather, and the bill was higher than the penalties for carrying extra fuel in all the flights the whole year.

Good luck:)