737ng Flight Planning

[ATC07]

Hi all!

I´m a little bit confused about what does "FINAL RESERVE FUEL" and "DIVERSION FUEL" exactly means? What things we have to take into consideration? and What are the correct 737NG values in pounds and Kg for: "FINAL RESERVE FUEL and HOLDING FUEL"?

I´ve recently made a fuel planning for the B736 but I´m not sure if all the information is correct or if something is missing.
Here we go!

TAXI FUEL: 500 lbs (15 min)
TRIP FUEL: 5815 lbs (465 nm 75min F350)
CONTINGENCY FUEL: 582 lbs (10 % trip fuel 7.5 min) Could be 5 %
ALTERNATE FUEL: 5783 lbs (465 nm 74 min F360)
FINAL RESERVE FUEL: 4000 lbs (I´m not so sure. I think this value is the minimum landing fuel after having burned TRIP, CONTINGENCY, ALTERNATE AND HOLDING FUEL)

* I think i´m missing the "HOLDING FUEL" value

Thanks in advance

Best regards

Santiago

[Reimers]

Final reserve fuel today was until some time ago called holding fuel. It no longer is because you are not supposed to actually use it during holding, but if you have to, it will keep you flying for thirty minutes more.

[Bearcat]

Final res= 30mins, about a ton on a320. Some airlines intruct their crews to declare a fuel pan when landing less than this and a mayday with 15mins left....

[BALLSOUT]

Ryanairs Min Fuel is 2300KG's This wil keep you in the air for more than an hour. ie on a normal flight to destination, without a diversion, you must land with not less thn 2300KG's.
Other companies, and other countries may well run to different Minimums. I am sure if you look back through the thread you will find examples of how to calculate the minimums but they must also never be les than 2300.

[aerobat]

The last time I looked in the Part A it said, " No Ryanair revenue flight shall be planned to arrive at destination with less than
2000 kg of fuel ".

[eckhard]

Fuel Planning

Hi ATC07,

Here are some notes which you might find useful. They are 'JAR-OPS generic' but I may have used some 'company-specific' terminology here and there:

FUEL PLANNING NOTES

TIF TRIP FUEL Fuel for take-off, climb, cruise, descent and approach at destination using forecast winds and planned Flight Levels on the route filed with ATC.

CONT CONTINGENCY 5% of TRIP FUEL to allow for unforecast winds, lower than optimum levels, ATC re-routes, etc.

DIV DIVERSION Fuel for go-around, missed approach, climb, cruise, descent and approach from destination to the alternate airport using forecast winds, levels and routing as listed on the flight log.

RES RESERVE Final Reserve sufficient for 30 minutes holding at 1500ft above the alternate airport.

REQ REQUIRED Fuel Required at the start of the take-off roll. It is the sum of TRIP, CONT, DIV and RES fuel. (Actually it is permissible to use CONT fuel before take-off, but unwise to use it all.)

DECMP DECOMPRESSION Not generally required for European operations. It is only relevant for long-distance flights over water (e.g. ETOPS). Sometimes referred to as ADDITIONAL Fuel

EXTRA EXTRA Extra fuel at the discretion of the captain to allow for holding at destination, anti-icing, etc. Can also include 'Tankering' Fuel.

TAXI TAXI Sufficient fuel allow for APU use, engine start and taxi before takeoff.

TANKS The Total of all the above. The fuel in the tanks before engine start.

Some other definitions:

FINAL RESERVE is enough for 30 minutes holding at the alternate airport (after diversion). If you dispense with an alternate (i.e. you 'commit' to landing at your destination), this is the minimum fuel that you must land with. If it is likely that the aircraft will land with less than this amount, you should declare a 'Mayday'.

TOTAL RESERVE is enough for a diversion to the alternate airport followed by 30 minutes holding. It is the sum of DIV and RES fuel. Sometimes called COMPANY MINIMUM RESERVES (CMR). Some companies have a 'minimum' CMR, e.g. 2000kg for a 737. I think this is the figure referred to in some posts.

PLANNED REMAINING is what you expect to land at the destination with. It is the sum of CONT, DIV, RES, DECMP and EXTRA fuel.

So you see there is no requirement to allow for 'holding' at destination. A sensible crew will take EXTRA fuel to cater for holding at destination, if they feel it is justified. On a 'normal' flight, they will arrive with PLANNED REMAINING, and so have some holding capability at destination in any case.

Hope this helps to clear up what can be a complicated subject (not helped by different terminology being used by different operators).

[ATC07]

Thanks all for your replies!!

eckhard, thanks for your very detailed info about this topic!! let me ask you something else.
Final reseve fuel is the same that Holding fuel, isn´it? So, in case of burning TRIP, CONT, ALTERNATE (DIV), What would happen If I need to hold over the alternate airport for example 10, 15 or 30 minutes? Obviusly I´ll land with less than the minimum fuel onboard (LOW FUEL gauges). Is that correct?

Thanks once!

Santiago

Pd.- If you have exactly values for yhe B737NG let me know please. Thanks!!!

[Pilot Pete]

ie on a normal flight to destination, without a diversion, you must land with not less thn 2300KG's

Are you sure that is right? Can Ryaniar pilots not decide to burn alternate fuel at destination as long as they comply with the JAR requirements? Sounds strange to me.

PP

[BOAC]

Originally Posted by rb

Nobody can give you exact values apart from taxi fuel which is usually fixed at about 200Kgs or 450 lbs

Taxi fuel is always at Captain's discretion, but COMMONLY 200kg is used as a company 'standard'. Other figures are not unknown. Agents normally ask for your chosen figure.

PP -I think 'plan to' was missing from Ballsout's post as aerobat has highlighted? Otherwise if you finished up with less than 2300kg on finals you would have to go round and stay up for ever

[Boingboingdriver]

fuel planning is all about knowing your route,AC knowledge,Op flight plan,weather and airport/ATC particularities.
I believe Ryan air forbids landing with less than 2 tons due to a possible low fuel procedure on short final.(open the crossfeed valve basically)and possible complications in case of a go around.(missed approach with a high gradient).
B737 700 in my company:200kgs taxi(we do have a minimum take off fuel)so extra fuel may be uplifted if taxi longer than 20 minutes(taxi is 10kgs/minute)ie deicing....
Final reserve is 1000kgs plus alternate.
However a JAR rule states no alt required if field at landing is cavok and multiple rwys(dont intersect with different approach aids used)...very delicate to use...
Then we have route reserve (200-250kgs),thats to account when u get lost or atc forgot you on a heading for hours;-)
And a company fuel for diversion.London for example is 550 kgs.

Good planning saves your company plenty of money, too poor planning costs your company even more and you get to work for your mistake;-)so far so good here!
Remember uplifting 200kgs each flight for no reason,40 sectors /month is equal to 8 tons times 12 thats 96 tons/pilot/year////pricy;-)

Captain standard

[Rainboe]

I would expect it to be planned to land with less than xxxxkgs at destination. One can't help the situation where one lands with far less having had to hold or cruise at low level, or had to divert to a further alternate. The 737 is quite happy landing with 1500kgs or less, I have checked it out! As for paperwork, as long as you have more than Final Reserve (30 minutes- usually less than 1200kgs) on shutdown (anywhere), paperwork is kept to a minimum!

[TopBunk]

Remember uplifting 200kgs each flight for no reason,40 sectors /month is equal to 8 tons times 12 thats 96 tons/pilot/year////pricy;-)

Uplifting fuel does not mean you burn it

[eckhard]

Hi ATC07,

Yes, If you burned TRIP and CONT on your way to destination and then decided to divert to the alternate, you would arrive there with FINAL RESERVE of 30 minutes fuel (assuming you had not loaded EXTRA or ADDITIONAL fuel). In this case you had better put out a PAN or MAYDAY as soon as you start the diversion, as it is likely that in the 'real world' you will land with less than final reserves in tanks.

With an urgency/emergency declared, ATC will (hopefully) give you direct routings, best altitudes, etc. The 30 minute's worth of fuel that you will arrive at the alternate with should allow for an approach, go-around, circuit and landing. If you do have to hold when you arrive at your alternate airfield, it is just not your day! This scenario explains why it may be preferable to 'commit' to the destination and use some of the DIV fuel for holding at destination, thus landing with more than RESERVE fuel.

'Committing' should not be lightly undertaken - there should be sensible protocols in place to ensure that a 'balance of risk' indicates that a landing is 'assured' at destination before dispensing with an alternate.

Hope this helps!

Sorry, I don't have any figures for a 737NG.
Eck

[Boingboingdriver]

TOPBUNK,

of course you dont burn it all, the 200 kgs that is
but u burn 7 percent of your uplift by carrying it ....not talking about higher fuel prices at specific airports...

captain standard

[BOAC]

Actually 3.5% of your EXTRA uplift is a more accurate guess.

[Sky Wave]

'Committing' should not be lightly undertaken - there should be sensible protocols in place to ensure that a 'balance of risk' indicates that a landing is 'assured' at destination before dispensing with an alternate.

If you decide to go to your alternate you are then committing yourself to the alternate as you'll not have enough fuel to go back to your destination. Therefore whatever happens you're committing to one airfield or another. I can't see any reason to go to an alternate if the weather at both airports is above Cat 1 limits. Both airfields are suitable for landing at, both airfields are within limits, one of them is where the passengers and crew need to be and the other isn't. All things being equal it's a no brainer.

I would however divert to the alternate if the odds of an assured landing favoured the alternate. (better weather if destination is marginal, an unknown or unreliable EAT at destination etc)

Two runways at the alternate airfield may also be enough to make me favour a diversion, however 2 runways at destination and a single runway at the alternate would swing it the other way. It can also depend on where you are. In the London area, if the sh*t really hit the fan, I'd used my alternate fuel (either by diverting or committing to destination) I'm still happy that I could get into LHR, LGW, STN or LTN using final reserve (on a mayday of course). Now if you were in an area with less airfields you do have to think about what happens if I divert or commit to a single runway airfield and an aircraft crash lands blocking the runway.

All I'm saying is that diverting should not be the default option.

[Boingboingdriver]

BOAC,
maybe..,my airline boeing representative told me once that 7 perc of our fuel uplifted is burnt by carrying it...but the uplifting of 200kgs for no specific reasons costs our company an average of 30 dollars depending on the airport its been uplifted of course.

Captain standard.

[eckhard]

Skywave - I agree with all of your points.

Boingboingdriver / BOAC - I think that the cost of carrying extra fuel is actually about 3.5% to 4% of the extra fuel for every hour that it is carried. In other words if you load an extra 1000kgs, your fuel burn will increase by about 35 to 40 kg/hr. So on a 5 hour sector, you would burn an extra 200kgs and arrive with only 800kgs of the original 1000kgs in your tanks.

Assuming an average European LoCo sector length of 2 hours, you would burn 70-80 kgs extra according to this formula. Maybe this is where your company representative got his figure of '7%' from?

Just my two cents' worth!

[BOAC]

We are now WELL off the OP question, but it is irrelevant to this discussion what % of your fuel you burn, since no-one has found a way of flying an airliner empty of fuel. What IS relevant is the amount of EXTRA fuel loaded that you will burn.

[Boingboingdriver]

During the summer months, 95perc of flights havent used the company Route Reserve of about 200kgs.That is 95 per of flights which took off with EXTRA FUEL uplifted it unecessarely.they landed with Off blocked with minimum block plus the route reserve plus any fuel saved between 10 kgs sometimes up to 600kgs!
Captain standard