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Overweight Landing

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Overweight Landing

Old 20th May 2023, 01:16
  #21 (permalink)  
 
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Chinese carriers don’t care about fuel saving. Being safe at all cost is their top priority. Knowing how picky they are if you do an overweight landing (>1.79g is considered an hard landing in my outfit) ;I would just hold until below max landing weight. Did they hold with gears up to be in the air for so long? Holding at green dot speed with gears down on A320 CEO you will burn over 4T/hour
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Old 20th May 2023, 04:54
  #22 (permalink)  
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Originally Posted by pineteam
Chinese carriers don’t care about fuel saving. Being safe at all cost is their top priority. Knowing how picky they are if you do an overweight landing (>1.79g is considered an hard landing in my outfit) ;I would just hold until below max landing weight. Did they hold with gears up to be in the air for so long? Holding at green dot speed with gears down on A320 CEO you will burn over 4T/hour
They were not holding but flying around a given area. Since fuel is to be burnt it will do a quicker job to fly gear down closer to 280kts.
However not sure if aircraft could be pressurized because gear down for two hours unpressurised will drive passengers crazy. It's bad even with pressurisation.
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Old 20th May 2023, 06:03
  #23 (permalink)  

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Originally Posted by Orange future
In all of the countries I have flown in this would not justify an overweight landing in a bus or a boeing!
That's a bold statement exactly in the face of OEM guidance.
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Old 20th May 2023, 06:41
  #24 (permalink)  

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Originally Posted by pineteam
Being safe at all cost is their top priority.
Eeehh... everybody wished. IRL the single highest priority is being compliant. Not that different from what happens elsewhere, but yes they do go to extremes.

Your post (part not quoted) suggest the PIC may have had a decisive say, and that's a very odd vibe.

My take will be hugely unpopular, saying once you get to the marrow (having clicked the performance boxes) the decision tips around the legality of the AFM non-compliance.

If you feel time pressure, do it.

If you feel it is useless to wait, get it approved and then do it.

Wargaming (skipping the obvious):

Engine fail - yes.

Operational Re-routing - no.

Failure affecting certified state (a.k.a. 'non-MEL) - most likely yes.

====== This is a good one:

After successfuly fighting a power bank fire that turned not easy to dispose of, the remaining extinguishers are below dispatch limit as well as the number of CC PBEs left unused.

Pushing for the trans-pacific sector has become untenable, and you are headed for Guam that is 60 minutes away.

There are no injuries or health complications among anyone on board, but the passanger mood is very awkward. Clearly, the 2 charred seats will get a huge exposure once the aircraft lands.

OPS cannot be reached.

The predictions from FMS show that upon arriving overhead Guam the airplane is overweight by 6x final reserve fuel mass (i.e. 1 hr with gear down).

(A) The quickest landing can be achieved by flying to Guam at high ETOPS Mach, and make an immediate overweight landing. Getting ugly dirty on the descent and approach (without a slow speed technique, however) will reduce the overweight from 6x FRSF_weight to 3x FRSF_weight, no less.

(B, C, D) middle options, compromises. Sacrifice something at the expense of half-meeting multiple targets)

(E) Using high-power Mach, the origin airport which is your operating base can be reached. Located 1 hour beyond Guam, the time to reach it is precisely equivalent to time required for a landing below MLW at Guam. Other words, if MLW is to be observed, the passanger's origin and your home base can be reached without a time penalty.
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Let the difference between the quickest OVWT at Guam and the quickest MLW be 1 hour. You ARE turning back with 1 hr to the earliest landing, overweight.

======= show of hands? ====


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Old 20th May 2023, 09:16
  #25 (permalink)  
 
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Originally Posted by FlightDetent
Eeehh... everybody wished. IRL the single highest priority is being compliant. Not that different from what happens elsewhere, but yes they do go to extremes.

Your post (part not quoted) suggest the PIC may have had a decisive say, and that's a very odd vibe.

My take will be hugely unpopular, saying once you get to the marrow (having clicked the performance boxes) the decision tips around the legality of the AFM non-compliance.

If you feel time pressure, do it.

If you feel it is useless to wait, get it approved and then do it.

Wargaming (skipping the obvious):

Engine fail - yes.

Operational Re-routing - no.

Failure affecting certified state (a.k.a. 'non-MEL) - most likely yes.

====== This is a good one:

After successfuly fighting a power bank fire that turned not easy to dispose of, the remaining extinguishers are below dispatch limit as well as the number of CC PBEs left unused.

Pushing for the trans-pacific sector has become untenable, and you are headed for Guam that is 60 minutes away.

There are no injuries or health complications among anyone on board, but the passanger mood is very awkward. Clearly, the 2 charred seats will get a huge exposure once the aircraft lands.

OPS cannot be reached.

The predictions from FMS show that upon arriving overhead Guam the airplane is overweight by 6x final reserve fuel mass (i.e. 1 hr with gear down).

(A) The quickest landing can be achieved by flying to Guam at high ETOPS Mach, and make an immediate overweight landing. Getting ugly dirty on the descent and approach (without a slow speed technique, however) will reduce the overweight from 6x FRSF_weight to 3x FRSF_weight, no less.

(B, C, D) middle options, compromises. Sacrifice something at the expense of half-meeting multiple targets)

(E) Using high-power Mach, the origin airport which is your operating base can be reached. Located 1 hour beyond Guam, the time to reach it is precisely equivalent to time required for a landing below MLW at Guam. Other words, if MLW is to be observed, the passanger's origin and your home base can be reached without a time penalty.
​​​​
Let the difference between the quickest OVWT at Guam and the quickest MLW be 1 hour. You ARE turning back with 1 hr to the earliest landing, overweight.

======= show of hands? ====


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Maybe I’m missing the gotcha, but return to origin seems an obvious choice to me.
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Old 21st May 2023, 01:57
  #26 (permalink)  

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I tried to play a no-good-choice scenario, an attempt to show the OVWT debate might be paradoxical.

To illustrate my point, that OVWT can be only evaluated by performance and legal assesment. Any 'safety' is vague, fuzzy, and moreover the evaluation could tip to the opposite side with adding / removing just a tiny little bit of information.

Towards your itch:

The narrative claims that extended flight is not desirable with depleted extinguishers and lacking PBE coverage.

For the unpredictable, the choice is made to seek an early landing, 'safety reasons', technically picking a more conservative course of action - placing bigger margins from an hypothetical undesirable aircraft state by reducing the probability through limited time exposure.

Here is the discontent -

We chose to reduce the airborne time, because the ship is no longer equipped to fight an on-board blaze,

however, at the same time

We chose to extend the airborne time by 100% over what was necessary

. Where is the consistency, cannot stay airborne long enough but decide to stay airborne twice as long as necessary?

😉


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Old 21st May 2023, 06:22
  #27 (permalink)  
 
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Originally Posted by FlightDetent
I tried to play a no-good-choice scenario, an attempt to show the OVWT debate might be paradoxical.

To illustrate my point, that OVWT can be only evaluated by performance and legal assesment. Any 'safety' is vague, fuzzy, and moreover the evaluation could tip to the opposite side with adding / removing just a tiny little bit of information.

Towards your itch:

The narrative claims that extended flight is not desirable with depleted extinguishers and lacking PBE coverage.

For the unpredictable, the choice is made to seek an early landing, 'safety reasons', technically picking a more conservative course of action - placing bigger margins from an hypothetical undesirable aircraft state by reducing the probability through limited time exposure.

Here is the discontent -

We chose to reduce the airborne time, because the ship is no longer equipped to fight an on-board blaze,

however, at the same time

We chose to extend the airborne time by 100% over what was necessary

. Where is the consistency, cannot stay airborne long enough but decide to stay airborne twice as long as necessary?

😉
A good scenario to think about for sure!

If the scenario left me with NO cabin fire fighting capability it may be a different decision making process…

Last edited by ScepticalOptomist; 21st May 2023 at 08:22.
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Old 21st May 2023, 07:33
  #28 (permalink)  
 
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Obviously the OVERWEIGHT LANDING procedure is an ABN procedure. Regardless, the FCTM “techniques” manual advises that an overweight landing can be performed "in exceptional conditions" (in flight turn back or diversion), provided the flight crew follows the OVERWEIGHT LANDING procedure. Pretty simple really….
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Old 21st May 2023, 11:12
  #29 (permalink)  
 
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Originally Posted by FlightDetent
I tried to play a no-good-choice scenario, an attempt to show the OVWT debate might be paradoxical.

To illustrate my point, that OVWT can be only evaluated by performance and legal assesment. Any 'safety' is vague, fuzzy, and moreover the evaluation could tip to the opposite side with adding / removing just a tiny little bit of information.

Towards your itch:

The narrative claims that extended flight is not desirable with depleted extinguishers and lacking PBE coverage.

For the unpredictable, the choice is made to seek an early landing, 'safety reasons', technically picking a more conservative course of action - placing bigger margins from an hypothetical undesirable aircraft state by reducing the probability through limited time exposure.

Here is the discontent -

We chose to reduce the airborne time, because the ship is no longer equipped to fight an on-board blaze,

however, at the same time

We chose to extend the airborne time by 100% over what was necessary

. Where is the consistency, cannot stay airborne long enough but decide to stay airborne twice as long as necessary?

😉
In deciding not to continue on with a presumably long flight over the Pacific with limited diversion options, we are trying to mitigate a fire onboard risk. But it doesn't necessarily mean it is a land asap situation.

If the reason or argument was not to fly a single minute longer than necessary, then principally you'd have to choose the nearest possible airfield - anything that comes your way before Guam?
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Old 21st May 2023, 23:39
  #30 (permalink)  
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Max Landing Weight (MLW/MLM) is a TCDS Limitation of the aircraft. While it is possible to exceed it as is the case with every limitation it is still a legal limitation of the aircraft, and to randomly decide to ignore a limitation places your license at risk. You can land overweight when it is a result of a procedure that calls for a land as soon as possible, or where there is a time critical event that affects safety of life. At every other occasion, the pilot is hanging in the breeze on liability as they have breached a pretty basic legal requirement, that is to fly the aircraft within it's limitations. That is an ICAO Annex requirement, so Orange is quite correct, his comment is not courageous, it is legally correct. Are there times that an OWL is justified? absolutely. If the failure to pressurise had resulted in a medical condition, you would be justified to conduct an OWL. To do an OWL, to deliberately breach a certification limitation of the aircraft can be considered reckless operation, (see FAR 91 or FAR 1.3 for a definition). If there is smoke, fill your boots, fire? same... an engine failure? depends, read the blurb.... sometimes absolutely, other times, might depend.

OWL for expediency should have the decision maker in front of the accountable manager explaining his/her/other actions.

Please also note that (IIRC) no OEM conducts auto land demonstrations above MLW(MLM), and most aircraft will have a caution or warning to that effect.

Is it possible to do an OWL, of course it is, assuming the pilot is not a drooling imbecile. Yet, every day, we manage to smack the ground with apparently qualified pilots with very high impact loadings within the normal envelope of the aircraft, so we can't guarantee not breaking planes by actually flying them well even when in the normal case. The OWL issue is a legal issue, not one of ego or competency, and any ICAO SARPS compliant regulator should have a serious concern if the guidance of an airline is "she'll be right, just don't stuff it up" in respect to wilfully disregarding a certified limitation. The follow up question from the regulator is "and what other limitations and regulations do you wilfully disregard?".

If it is a time critical safety matter, fill yer boots, if it is for convenience, log the overtime, IMHO.

Last edited by fdr; 21st May 2023 at 23:59.
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Old 21st May 2023, 23:43
  #31 (permalink)  
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Originally Posted by Rico_Corp
Obviously the OVERWEIGHT LANDING procedure is an ABN procedure. Regardless, the FCTM “techniques” manual advises that an overweight landing can be performed "in exceptional conditions" (in flight turn back or diversion), provided the flight crew follows the OVERWEIGHT LANDING procedure. Pretty simple really….
An airturn back and a diversion are by definition not exceptional conditions, they are planned contingencies. Conducting an OWL due to inconvenience of a schedule disruption that may otherwise occur isn't going to work when the feds start looking at your license and whether you are in violation of air law. Better have a really good time critical justification to break the law.
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Old 22nd May 2023, 11:27
  #32 (permalink)  
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Please also note that (IIRC) no OEM conducts auto land demonstrations above MLW(MLM), and most aircraft will have a caution or warning to that effect.
Safety first issue #12 July 2011 Automatic landings in daily operations


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