Minimum fuel in tanks for a B737-300

[Current B737 Driver]

Looking for some guidance on what most carriers use as MINIMUM fuel in tanks for landing for a B737-300. I realize that 1676 is minimum fuel for electric hydraulic pumps on ground. MINIMUM fuel in this case is fuel remaining after you have held at destination then diverted to your ALTERNATE.
Looking forward to your response.

[aviatorhi]

Haven't flown the 737-300, but most minimum "desirable" fuel requirements at landing (which I've seen) are structured the following way:

Minimum manufacturer specified fuel at touchdown
+
Fuel needed to conduct a go around, fly a standard VFR pattern at 1000 AGL.
+
Fuel quantity indicator error
=
Absolute minimum "desirable" touchdown fuel.

I suspect you might find something in the limitations section of your Aircraft Manual that discusses this.

[BOAC]

Current - in what sense do you use 'minimum'? Company absolute minimum or planning minimum/legal minimums/fuel feed considerations/gauge errors or what? What is wrong with 'Final Reserve' as a concept?

[ImbracableCrunk]

Current,

Like BOAC suggested, you could be a bit more specific. US Domestic? ICAO?

Your location says "MIAMI." What's wrong with 45 minutes at cruise?

BOAC - I suspect many 'Mericans! will tilt their heads a bit and furrow their brows if you use the term "final reserve."

[BOAC]

Aha! Two countries separated by a common language again?

PS It was done deliberately for the very reasons you posted :)

[dantealighieri]

Looking for some guidance on what most carriers use as MINIMUM fuel in tanks for landing for a B737-300. I realize that 1676 is minimum fuel for electric hydraulic pumps on ground. MINIMUM fuel in this case is fuel remaining after you have held at destination then diverted to your ALTERNATE.
Looking forward to your response.

according this post
if in a flight plan we have : block fuel 5000kg
trip 2500kg
taxi 200kg
MDF 2300kg
trip to ALT 1300 kg
is it legal (!)to land to alternate airport with 1000kg fuel in the tank
( minimum reserve)???
tks for your opinions

[graziani]

in my opinion ,if you land at alternate airport with less than 1676 kg it is illegal ; you do not respect the lim B373:=:=:=:=:=:=

what about ryanair!!!!!!!

[chimbu warrior]

in my opinion ,if you land at alternate airport with less than 1676 kg it is illegal ; you do not respect the lim B373

Graziani, if you are referring to the requirement for >760 kg fuel in each related tank, I think you do not understand the reference to the minimum fuel for ground operation of the electric hydraulic pumps. This is a caution in FCOM Vol 2 13.20.3 not a limitation.

According to the manufacturer, it is quite okay to land with less than 1520 kg of fuel, however the electric hydraulic pumps must then be turned off after landing.

[FlyingStone]

I wouldn't be too worried about exceeding the minimum 760 kg/main tank limit (actually it's not an FCOM/AFM limitation) for elec hydraulic pump cooling. You have an overheat light anyway, so you can shut it down if it really overheats or at latest on ground, as per FCOM recommendation - when reduncancy of hydraulic systems is not as urgent as inflight.

Have a look at Minimum Fuel Operation NNC - it is designed for flying with less than 453 kg in each main tank and it doesn't even mention fiddling with hydraulic pumps...

[LeadSled]

Folks,
First of all, agree on what "minimum fuel" means.

Boeing published "minimum fuel for approach" and the definition of that is roughly "that amount of fuel, below which the Boeing Company will not guarantee the continued flight of the aircraft".

ICAO, and many airlines, specify "minimum fuel in tanks at the end of the landing roll", it achieves the same object as the Boeing figure, you will have enough fuel that all engines will be running at touchdown.

You will get low fuel pressure warnings under braking, fuel pressure surges etc., but at least the engines will be running.

The above came about as a result of hard experience, including some aircraft lost will all aboard, out of fuel( Portland, OR, and New York, to name two) and some desperately close goes, engines flaming out on final.

Do not confuse this figure with airline fuel policies etc, "minimum fuel" is the last ditch fuel, when you have to be on the ground, wherever that might be.

Always, but always, know that figure for your aircraft. Remarkably, it is often very close to 30m calculated at the holding rate for the weight, and this is what ICAO requires for minimum fuel.

Tootle pip!!

[Derfred]

That's a curious post LeadSled.

Am I interpreting you correctly that Boeing will not guarantee that the engines will keep turning with less than 30 minutes of fuel in tanks?

I was under the impression that there was some aircraft design rule that engines must still be turning as fuel gauges click to zero.

If I am dealing with a greater emergency with 30 minutes of fuel left in tanks, I would really like to know whether my engines will actually keep turning for those 30 minutes.

[piratepete]

Most likely a similar way to answer this question, but for a 767 you need to look in the Boeing FPPM to get the FINAL RESERVE figure which under ICAO is 30 minutes of HOLDING FUEL at 1500 feet and varies from 4400 lbs at MLW down to 3800 lbs at very light weights.The hydraulic pumps are not in the wings but some hydraulic plumbing is, and this is to provide some cooling.There is no limitation in this regard but you might want to consider turning off some hydraulic pumps upon landing to avoid overheating.

Under most rules intentionally landing with less than the FINAL RESERVE is a MAYDAY situation, its an emergency, however how much fuel DO YOU ACTUALLY NEED in tanks while still in the air to be assured of the engines still turning/burning? This is generally considered to be , under JAA rules, enough to go-around from final at 500 feet, climb to 1000 feet circuit altitude, complete a quick orbit/360 back onto final and land.The fuel needed for this I seem to recall is of the order of 1200 kgs or 2600 lbs.I have actually experienced one "event" where, due to a variety of factors, was faced with having only 4000 lbs in tanks while on final in marginal WX and it was very unnerving because the FMC went haywire with a calculation of ZERO FUEL ON ARRIVAL, the FQIS was also weird now and again indicating ZERO, also the EICAS kept warning LOW FUEL messages.We shut down with exactly the legal requirement of 3800 lbs.I shut down one engine on touchdown, no reverse on the other donk, no APU until at the gate etc etc......Peter.

[Goldenrivett]

Hi Derfred,
I was under the impression that there was some aircraft design rule that engines must still be turning as fuel gauges click to zero. I would really like to know whether my engines will actually keep turning for those 30 minutes. Correct.
All manufacturers of commercial aircraft have to establish useable & unuseable fuel. The unuseable fuel is included in the dry operating weight.

"Fuel quantity indications
The primary function of the system(s) is providing usable fuel quantity indications. This includes the total usable fuel quantity which shall be permanently displayed and be easily and directly readable by the pilots; indeed, this is considered as essential information which shall be regularly checked by the pilots per operational regulation. The usable quantities of each individual tank must be available as well but it is acceptable that they are displayed only when required (on demand or automatically)."
https://easa.europa.eu/system/files/dfu/NPA%202011-13.pdf

piratepete,
I shut down one engine on touchdown, no reverse on the other donk, no APU until at the gate etc etc......
You made far more work for yourself than necessary. It's the remaining fuel on Landing that was important - not at the gate.

[Cough]

I shut down one engine on touchdown

If you had said shutdown at the end of the landing roll, that wouldn't have caused me to stir at all. At touchdown???? :mad:

Madness! Make sure you are down to taxi speed prior to loosing all the redundancy the second engine affords you.