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777 Energy management tips on approach

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777 Energy management tips on approach

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Old 5th Sep 2023, 05:40
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777 Energy management tips on approach

Hi all,

Are there any recommended “low drag” techniques in the 777? I find that approaches in this plane seem to be rather “messy” in that flaps and gear seem to be extended much earlier than I’m accustomed to on a narrow body. My company recommends landing flap to be set by 1500ft, and we’re always stable, but it seems like we’re dragging the gear and flaps along for much longer than we really need to in order to be stable.

If ATC has no speed instruction, what speed management gates do you aim for?

For bonus points, any tips on a “clean” approach profile at UK airports where they want 160 to 4?

Thanks
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Old 5th Sep 2023, 06:31
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Unfortunately, wide body ops tend to be a little les efficient than what we were used to on the smaller jets. In the age of being stable, and compliant for ATC, it's just a "safer" way of operating - especially as wide body ops tend to be longer duty hours and with less recency.
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Old 5th Sep 2023, 07:21
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Long time out of it but recall, if you want 160 @ 4 you will need to will need to have your final flap running before you get to 4. 1000 ft stabilised will be unobtainable otherwise.
Only other gate if I recall was, on slope, 210/220 F15 no gear @ 12
Willing to be corrected by current crew.
Maui
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Old 5th Sep 2023, 07:25
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Taking F25 or F30 at 4.5d seems to work…..assuming you are Gear Down , F20 already…..
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Old 5th Sep 2023, 08:49
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You can always tell ATC if you cannot comply with an approach speed owing to performance.

Tell them what you can give them instead - say, 160 to 5nm - and they will knit you in with the others.
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Old 5th Sep 2023, 10:53
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Gear down, flap 20 at 2000ft RA. Then flap 25 or 30 at 4.5D, select VREF at 4D. Works for us and we usually fly 160 to 4 miles.

USA ATC either have no idea how aircraft work or operators there are willing to take a more relaxed view to stable approach policies based on some of the requests we get (180 to 4 being the most recent request which was politely refused).
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Old 5th Sep 2023, 13:37
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Originally Posted by Fursty Ferret
Gear down, flap 20 at 2000ft RA. Then flap 25 or 30 at 4.5D, select VREF at 4D. Works for us and we usually fly 160 to 4 miles.

… (180 to 4 being the most recent request which was politely refused).
Gear down at 2000’ was also my final gate. Occasionally used F20 (without gear) when given a late speed reduction just as we captured the glide.

250 to 5000’ then F1 & F5 as the speed bleeds off at idle with continuous descent.

Also regularly refused ‘180 to 4’ in the US - instead offered them 180 to 6, or 170 to 5.
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Old 5th Sep 2023, 15:27
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The difference between 180@4NM and 160@6NM is 10 seconds at touchdown. There is absolutely no reason to ask the pilots to keep going fast until the last mile. Controllers should be trained to ask what Vfas is, and plan for adequate separation based on everyone flying their VFAS latest at 1000'.
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Old 5th Sep 2023, 20:14
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I find that under normal conditions, i.e. not too adverse, you can do 160 to 4, 170 to 5, 180 to 6, etc. without too much trouble. Clean and F1 will accelerate down a 3deg glide, unless there is a significant headwind. F5 juuust about holds the speed and F15/20 need a little bit of power.

Gear at 2,000AAL and land flap just after 5 miles does the trick for stable at 1,000'. That’s about as clean an approach you can make as the drag only really comes in with F25 and F30, so the aircraft is still quite slippery with lower flap settings. The speedbrake gets used a lot - it’s a primary flying control on the 777!
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Old 4th Oct 2023, 18:19
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At certain bustling U.S. airports, ATC may instruct you to maintain 180 kts until 5 miles. If landing performance isn't a factor, using Flaps 25 during the landing can readily meet the ATC requirement.
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Old 5th Oct 2023, 06:09
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Thanks for the input all. I'm coming to realise that configuring the 777 may not be as neat and tidy as the A320.
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Old 5th Oct 2023, 06:31
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Maybe that is because it's an aeroplane rather than a s.it box.
(Ducking for cover)
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Old 5th Oct 2023, 08:30
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(Don't feel bad, maui. Not all pilots are clever enough to understand and fly Airbus FBW..........)

.

Last edited by Uplinker; 5th Oct 2023 at 08:50.
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Old 5th Oct 2023, 09:16
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Originally Posted by Check Airman
Thanks for the input all. I'm coming to realise that configuring the 777 may not be as neat and tidy as the A320.
The following comment may be controversial but I always reckoned (and sometimes briefed) that it's worth thinking of the speed brake on the T7 as a primary flight control, rather than the control lever being "the stick of shame".



Last edited by wiggy; 5th Oct 2023 at 10:57.
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Old 5th Oct 2023, 11:16
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It is worth bearing in mind that whilst there are general similarities when operating both the 777-200 and 777-300 variants, the 777-300 does require a bit more thinking ahead, regarding decisions about where/when to carry out gear and flap extension for landing. The 777 is a bigger, heavier airframe, so all other factors being equal, it tends to have a higher minimum approach and landing speed. Ensuring you can meet ATC requests like 160 kts to 4 nm needs to be considered carefully at the Arrival Briefing stage, and with a 777-300 it is often necessary to ask for a few more knots on the speed, and an extra nautical mile or two on the distance, to ensure an orderly, unhurried configuration process.

Additionally, if landing at a relatively unfamiliar isolated destination, i.e. the nearest suitable diversion is further away, when compared to your other more commonly visited destinations, you will be carrying more diversion fuel than usual, and so, again, the effect of that landing weight and it's associated speeds, need to be planned for, so that a timely message can be passed to ATC, for their approach planning purposes. This principle applies to both the 777-200 and 777-300 variants, of course, but some may be a little taken aback when it is added to the generally increased landing weight of the 777-300.
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Old 5th Oct 2023, 13:33
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Originally Posted by FullWings
I find that under normal conditions, i.e. not too adverse, you can do 160 to 4, 170 to 5, 180 to 6, etc. without too much trouble. Clean and F1 will accelerate down a 3deg glide, unless there is a significant headwind. F5 juuust about holds the speed and F15/20 need a little bit of power.

Gear at 2,000AAL and land flap just after 5 miles does the trick for stable at 1,000'. That’s about as clean an approach you can make as the drag only really comes in with F25 and F30, so the aircraft is still quite slippery with lower flap settings. The speedbrake gets used a lot - it’s a primary flying control on the 777!
i will vouch for all of the above….
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Old 5th Oct 2023, 13:42
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Originally Posted by wiggy
The following comment may be controversial but I always reckoned (and sometimes briefed) that it's worth thinking of the speed brake on the T7 as a primary flight control, rather than the control lever being "the stick of shame".
And I agree with that as well. You need to use the SB on the 777 as a flight control.
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Old 5th Oct 2023, 17:13
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Originally Posted by SOPS
And I agree with that as well. You need to use the SB on the 777 as a flight control.
I completely agree. Coming from the 737NG, I used to call the T7 SB the magic lever. While I aimed at not using It, I never felt ashamed for doing so. It gave me the warm feeling that It could bail me out of almost any situation and without any flap restriction. What a tool, I just loved It!
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Old 5th Oct 2023, 18:59
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Widebodies tend to be a little more 'slippery' compared to narrowbody aircraft - making energy widebody management somewhat more tricky.
At EIS of the 767, Boeing actually got complaints about how difficult it was to get the 767 to slow down/descend relative to the aircraft they were replacing.
Part of that is just improving technology with newer aircraft, but it also has to do with the target mission - widebodies are designed for longer, faster flights than their narrowbody counterparts, so there is more emphasis on drag.
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