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Airbus Energy Management.

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Airbus Energy Management.

Old 5th Jun 2019, 11:25
  #21 (permalink)  
 
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Because speed brakes should not be instinctive especially at high altitude when slow (for ATC). Their effect of the min speed is marked and deployment is to be a conscious decision.
And how would the other guy know how much you're extending
And you could hit the rudder by accident...

I'm sure there's more!
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Old 5th Jun 2019, 11:48
  #22 (permalink)  

Only half a speed-brake
 
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junction34 If there is a policy of stable approach based upon RAD ALT, it almost deserves to be violated.

Del Prado Out if interest, would there be a similar statistic WHERE is the point when crews stop maintaining 160?
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Old 5th Jun 2019, 13:43
  #23 (permalink)  
 
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F3 160 selected until 4.5D, manage speed, then gear down, F full, landing checklist, stabalised at 1000 no problem. It doesn't always have to be F2 then gear. Use your drag devices as required, my 2c anyway.

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Old 5th Jun 2019, 15:35
  #24 (permalink)  
 
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I drop the gear at 4.5 (with flap following when gear down) and then manage speed at 4 (as requested). Always configured by 1000’ aal and usually within Vapp +10 but as stated by some others in our company with 30kts is fine so long as you have Vapp by 500 RA. Yes it’s busy but perfectly manageable if youv’e discussed it beforehand.

If there’s a tailwind then i’ll tell ATC and ask to slow down earlier. They’ve always been accommodating and would prefer that to someone doing so of their own volition, which seems to be the case a lot when you look at the stats
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Old 6th Jun 2019, 03:17
  #25 (permalink)  
swh

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I have gear and full flap out before 4.0 miles and only start to decelerate at 4.0 miles.

Our stabilised approach criteria says on path, landing configuration, and checklist complete by 1000 ft. Speed commensurate with conditions.

if your company policy is holding you back from not maintaining 160 to 4, identify the problem and get it fixed. The A330 even at max landing weight and a tailwind will be on speed and have thrust above idle before the minima.

It is an unreasonable expectation to think other airlines should go around or hold longer because your company policy is holding up an efficient sequence.

If everyone flew their assigned speeds exactly, and not this B/S 5-10 kts, or 1-1.5 no buffer (there is zero pilot buffer on ATC assigned speeds and distance) we would have less holding, and more landings per hour.
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Old 6th Jun 2019, 17:03
  #26 (permalink)  
 
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Thanks for all the comments, lots of interesting points for me.

If you start to slow at 4.2-4.5 you’re not going to lose more than 10kts by 4d and that’s fine, it’s the ones that start to reduce at 5.5 or more that ruin it for all.

I understand the stability criteria and it must be very tempting to err on the side of caution but slowing early is not a ‘victimless crime’ at busy airfields and I’m surprised the airlines haven’t identified this as an area to improve and find a better balance between stability criteria, fuel burn/noise on approach AND landing rate.
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Old 6th Jun 2019, 18:04
  #27 (permalink)  
 
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Airlines should reduce the stabilization height for 4nm 160 airports to five hundred feet. So it's not left to individual pilot in varying circumstances such as GW, winds etc. In case of1000 ft stabilization they should lay down a standard procedure. Be configured before 4nm with landing CL holding at flaps three. Crossing 4nm speed managed flaps full. You can expect to loose minimum 10 to 15 kts in next 1nm.
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Old 6th Jun 2019, 18:39
  #28 (permalink)  
 
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For me it depends on how i started the Approach, if it’s all been well managed with full mental & cockpit prep to land i like to do the High speed App to set L/G down with speed managed after 4.5~5NM , in the contrary if its been a stressful flight with shitty CPT or in long Night flight I rather to do it as slow as it can get with Flaps 2 at the FAF , the speed is under controlled after FAF Gears down and so on , so i think its all about the your situation and how you feel .
Cheers
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Old 6th Jun 2019, 19:04
  #29 (permalink)  

Only half a speed-brake
 
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Del Prado I am really happy for your input here.

These would work on your side if implemented - although not realistic. Just a thinking exercise.
- move the limiting point further, 4.5D
- add a message to ATIS at peak times: "High flow rate. Keep assigned speeds strictly on final, lest wing-tip clearance is not assured." The second part is already on the tape at Heathrow
- if somebody violates by more than 1,5NM, take them out of the sequence. Serious, twice in a single month and you will NEVER have that airline in your stats again.

For the small Airbuses, there is an issue. Strict adherence to all historical 1000' criteria and LP/LD + fuel-saving (ehm, carbon lean, green ops) approach is not compatible with the 4,0D/160. Something has to give. If the incumbents devised a clever way that works on a large scale basis for them, it must be possible to propagate that to other operators. Infrequent visitors maybe not too much.

Did you know, that apart from UK and FRA and AMS (cannot really recall anywhere else), the 180 knots restriction is never amended or lifted - unless separation critical? That pilots as a daily operating practice need to second-guess "how far do you want that"?
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Old 6th Jun 2019, 19:51
  #30 (permalink)  
 
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This is an interesting topic. Having lived through all sorts of variations of speed requirements, stable approach policies (from ultra-strict to none at all) and aeroplane limitations/SOPs, I think it has got faintly ridiculous now. Many airlines’ SAPs are borderline incompatible with some airfields’ restrictions and aircraft end up being operated in a manner that is not really what you would call good airmanship in the widest sense.

Why do we try and fly stable approaches? Well, one reason is because the employer says so but more importantly, it allows a crew to monitor their aeroplane and the environment and react in a timely and appropriate manner to any issues. If large part of available capacity is used to make artificial gates that are sometimes mutually conflicting, there follows that there is much less capacity to assess and predict. I have been on flight decks where three or four pilots are so busy with the speed control and stability process that the proverbial gorilla could climb over the windscreen and no-one would see it, which is not a great place to be.

Where is one of the worst places to encounter microbursts and/or windshear? Low level near an airport, so hanging on the thrust levers and speed brakes in an odd configuration approaching 1000R will mask some signs that things may be going wrong and if they do, make the recovery that much harder.

IMO there needs to be a bit more joined-up thinking involving all stakeholders (I’m starting to sound like an exec.) and not having external requirements coming from different directions. In my airline we have a 1000R stable policy but you can legitimately bust that if it’s because of ATC speed control - where’s the sense in that? Nasty things can happen irrespective of whether you’re under speed control or not.
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