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flaps 3 landing A320 to save fuel

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flaps 3 landing A320 to save fuel

Old 3rd Jun 2013, 08:44
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flaps 3 landing A320 to save fuel

Hi , I'd just like to know if there are companies that use flaps 3 landings as a fuel policy and if so , did they have substantial savings in doing so . Thanks
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Old 3rd Jun 2013, 09:10
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Yes many companies use flap 3, it's the normal landing flap setting at easyJet and they claim significant savings across the fleet from it.
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Old 3rd Jun 2013, 09:23
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Difference of between 5kg (empty A319) to 15kg (heavy A321), which adds up over a fleet of 250 aircraft.

Offset by 2 minutes taxiing, so if you can make an closer exit nearer the terminal then better to do flap full and then SE Taxi in.
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Old 3rd Jun 2013, 10:20
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Flap 3 is also good for the community - as was in this months or lasts newsletter for LGW based EZY pilots.... Along with the associated graphs
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Old 3rd Jun 2013, 11:19
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Can anyone explain me how fuel saving is achieved with such a low number ?
5 kg of fuel is below the FQI system accuracy

If you were to land with 3000 kg of fuel with flaps full, with a flap 3 landing , you would land with 3005 kg.
Now let's say that the next flight requires 6000 kg of fuel. The uplift should be 6000-3005 =2995 kg

And finally after refuelling you end up with 6080 kg . Total uplift was 3075 kg so 80 kg more than expected uplift . After refuelling you never get the exact figure requested.

So where was the fuel saving in this example?
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Old 3rd Jun 2013, 11:20
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Duuuuuude

Last edited by de facto; 3rd Jun 2013 at 11:23.
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Old 3rd Jun 2013, 12:02
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The down side is that it puts you very close to tail strike attitude in a 320 (not a problem in 319 or 321) which is enough to put most people off doing it at my place.
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Old 3rd Jun 2013, 12:05
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flaps 3 landing A320 to save fuel

Many thanks for the feedback....
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Old 3rd Jun 2013, 12:13
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So where was the fuel saving in this example?
Back to the Citation for you, sonny Jim!
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Old 3rd Jun 2013, 12:15
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Hey Citation2,

As you point out, some things are constant variables - in this case - you (almost) always get a few drops more than expected.

Assuming that is (almost) always the case regardless of whether you do a flap full or flap 3 landing, then a flap 3 landing still saves 5kg-15kg (or whatever) of fuel compared to a config full.

To answer your question, assuming the fueller sets 6.0 in the fuel panel and you end up with 6080kg irrespective of your starting fuel, the fuel saving is where the refueller only uplifts 3075kg instead of 3080kg.
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Old 3rd Jun 2013, 12:18
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Citation 2 and Max Angle
All the calculation you did happens even in flaps full. You may not be able to uplift 5kgs less but even 3 kgs is saved out of the 5kgs multiplied by 100s of sectors over one year amounts to something. About the pitch attitude is to remember that it is already in landing attitude all you need is controlled thrust reduction without much flare. Airlines wanting this should gradually introduce it in SIM checks.
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Old 3rd Jun 2013, 12:42
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it's the normal landing flap setting at easyJet
Ha ha ha ha!
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Old 3rd Jun 2013, 15:43
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It should be student88 anyway... I think you are an easy driver... Check your VistAir - a new manual was issued today covering this very subject.

If every A319 in easyJet did a flap 3 v flap full landing it would result in a saving of £3.0m, for the A320 its £550k

The biggest saving that we as crew can make, is not carrying fuel above OFP when there is no justification for doing so, I understand that we will soon be having an update to our OFP's showing the percentage of flights that operated on that sector without burning more than OFP fuel. (98-99% of flights)

But yeah, unless unable for operational reasons you should be doing a F3 landing, and it is the normal landing configuration to be used.
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Old 3rd Jun 2013, 19:30
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It says in the manual in big bold writing that flap 3 or flap full will be used normally for landing, along with requirements for flap 3 like extra care to be stable. I've seen maybe 3 people in 12 months do a flap 3.

I don't think many really care about flap 3.
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Old 3rd Jun 2013, 19:41
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SC, like I say if you read the new manual as published today.. AGAIN it goes on to stress we should all be doing flap 3 landings unless there is an operational reason why we can't.

Just below the statement you quote in our OM-B it says:

FLAP 3 OR FLAP FULL ARE THE NORMAL LANDING CONFIGURATIONS.

Flap 3 should be used for normal landings provided:

From today's publication:

Flap 3 Landing
The SOPs recommends the use of Flap 3 for landings for fuel savings as well as in the case of turbulence or wind shear. Flap 3 landings are slightly ‘different’ than Flaps Full landings.
Some factors that do require operational considerations are:
• Care must be exercised to achieve a stable approach
• No technical defects affecting landing performance note that some abnormal
conditions may require Flap 3 for landing
• No contamination
• Significant tailwind expected on landing
• The IFLD computed from the LPC or QRH In Flight Landing Distance +15% is less than the available landing distance
Consideration should be given to the increased taxi time that may result from a Flap 3 landing and the associated increase fuel burn. A319 burns 16 Kg more for a Flap Full landing/A320 burns 9Kg more for a flap full landing. In rough numbers, the breakeven point is 900m for A320 and 1700m for A319. This can be applied to any airport when Flap 3 will result in different exit point and longer taxi routing.

Last edited by airbus_driver319; 3rd Jun 2013 at 19:56.
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Old 3rd Jun 2013, 20:58
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ad319, you make me laugh. Your saving is probably correct at LGW where you are instructed to slow down to 160 at 10nm and maintain it to 4. But there is life outside Gatwick...
I am based at RAK and each time 28 (25km vis and clear sky) is in use, almost all the orange guys fly a full IFR procedure, followed by a circle to land with gear down and F3 instead of a, straight forward, visual approach. Did you save 9kg or did you just waste 491 kg?
When I flew the airbus I saw people configuring ealier on a F3 landing, reducing the benefit to almost zero. You only save the fuel if you accept that your approach will be stable 100-200ft lower than on a F full landing.
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Old 3rd Jun 2013, 21:08
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Of course we configure earlier. Configuring for a Flap 3 takes longer, as you know, because the lower final flap drag means an increase in the time taken to reduce to Vapp... hence the earlier configuration. This all happens at idle thrust.

Assuming you start to configure at a point from a Thrust Idle G/S descent (Conf 1) which enables you to become stable at 1000ft as with Flap Full, the timing of that point will make no difference to fuel consumption. What makes the difference is flying the remainder of the approach below 1000ft at 45% N1 instead of 55%.

Just saying...

Last edited by The African Dude; 3rd Jun 2013 at 21:23.
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Old 3rd Jun 2013, 21:15
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Sarah, you may laugh at the savings on a per flight basis - however in an airline the size of ours it results in a saving of over £3m a year. I don't think that is a figured to be scoffed at.

A snippet from our May newsletter, affirming the position re flap 3 landings.

"In recent issues of the newsletter we have highlighted the Ops Manual B requirements of using Flap 3 as standard for landings (as seen to the left).

It has come to light that some crew are under the impression that there has been a change in stance or SOP regarding the use of Flap 3 – due to a perceived requirement to slow down earlier to achieve a stable approach. This is not the case, and the current SOP to use Flap 3 for normal landings is still active."

Last edited by airbus_driver319; 3rd Jun 2013 at 21:19.
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Old 3rd Jun 2013, 21:32
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Eh which new manual?
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Old 3rd Jun 2013, 21:32
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Last time I used F3 for fuel saving, we got a "low energy warning", which ended up in a go-around, burning up additional ~400kg... Ooops, there go my savings...

P.S. Question for the EZY guys - do you ever use F3 at LTN?

Last edited by C_Star; 3rd Jun 2013 at 21:35.
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