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Wrong weight entry … again

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Old 9th Jul 2010, 18:01
  #41 (permalink)  
 
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No, he's not. There is no safest course of action anymore, but for management there always is a cost saving way.
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Old 9th Jul 2010, 19:10
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Discord, I remember very well another occasion when STAN saved
us from embarrasment. A load-controller ( big-mouth ) had made a
considerable mistake which was discovered as soon as the Merchantman
moved. Although corrective action was taken immediately and there was a happy end, I wished for all my airline life that all aircraft were fitted with something like STAN.

BEA 71
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Old 9th Jul 2010, 20:17
  #43 (permalink)  
 
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To reply to an above post, it would not be difficult to have a system where TOW, Rwy and Temp from automated METAR retrieval could then calculate V-speeds and put them on the loadsheet as one last, final gross error check.

Yes I know that MEL items, flap settings, anti-ice etc will alter take-off settings, but it would be better than this situation at the moment.

The technology should be there, it shouldn't be relied on, but would be a little like the third AI.
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Old 9th Jul 2010, 21:18
  #44 (permalink)  
 
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Amazed ...

As a naive observer, I'm amazed that these ac can take off when the weight has been so much underestimated.
It means to me that they may have large built in safety margins.
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Old 9th Jul 2010, 23:35
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I think that there are too many distractions in the modern cockpit.
Too many people coming in with papers to sign which breaks the routine of the crew. They then try to do more than one item at once to get back on schedule.
Data entry has always been a problem not just with airlines.
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Old 9th Jul 2010, 23:45
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I'm surprised that this thread has reached the third page before someone raises the idea of calculating the expected time to V1 (or ideally some lower speed) and rejecting the take off if you are not going that fast by that time. The idea was mentioned independently at least twice in the MEL incident thread.

Some people thought it a reasonable addition to the procedures, others implied that it was just another straw on an already overloaded camel at a particularly busy time.

As an afterthought, getting to the monitored speed (half V1?) too soon could also catch the case where half the fuel has been left behind.
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Old 10th Jul 2010, 00:47
  #47 (permalink)  
 
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Just a thought. If the calculations are correct and the engines are working as advertised then the aircraft should accelerate at a certain rate. Would it not be possible for the FMS to provide the crew with a time to say 80 kts based on what they have entered. Start the stopwatch at breaks release and if there is a significant discrepancy then the take off can be aborted rather than have an 'oh sh@t!' moment after V1.

Whilst there are many that believe rules of thumb should be enough I think that the combination of significantly different: loads, fuel, ambient conditions, and runway lengths that exist for long haul ops combined with the comparitively small numbers of take offs per month per pilot, means it is unrealistic for the crews to detect an error based on the 'vibe and the Mabo'. As was mentioned above, once can be put down to pilot error, but this seems to be happening regularly enough to consider it a systemic problem.
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Old 10th Jul 2010, 01:46
  #48 (permalink)  
 
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Devil

Essentially the issue is a matter of increasing complexity in an already complex system.
The FLEX/RTOW take offs are a means of safely borrowing from safety to increase system efficiency by saving fuel and engine life by only using as much as you need.

This is an effect of added technology, and it introduces a level of coupling such that the outputs in terms of V speeds and flex temperature are not necessarily obviously wrong, as the variables involved make it intractable to get a simple rule of thumb.

I was dismayed by the AAIB suggestion to use EVEN MORE automation and technology.

Ironically some airlines use a simple error trap in the RTOW calculations so that it will spit back an error message on ACARS if the TOW from the pilot is less than the MZFW. In this case it would have worked, as would the previous case in MEL.

As was the case of the BA B744 in JNB, the coupling is very tight on takeoff, so I admire and respect any pilot that can get the aircraft safely off the ground in these conditions.

If is easy to point the finger of blame to the unfortunate pilot who may have contributed the proximal failure in the 'chain of events', but this is a systems accident that has manifested itself repeatedly, and is a function of the system and the relentless trade off of throroughness for efficiency.

Discuss
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Old 10th Jul 2010, 02:49
  #49 (permalink)  
 
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Our freighters have the mass / balance sensing struts and it is a great backup to the load-sheet numbers. Our procedures say that we have to re-check the pallets if we are more than 3% off the computed TOW or CoG. This is rare, but occasionally happens. It is usually a ramp issue (not very level), I have never seen it be the loading.

I would imagine that with passengers the airlines don't want to scrap the standard weights because they would loose out on revenue. I ask you, how many American adult males weigh 180 lbs?

Obviously, a weight sensing system would have to go hand in hand with accurate loading (ie, weighing passengers) which is easily done - the technology is used for bags when it comes to making passengers pay for extra luggage weights.
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Old 10th Jul 2010, 05:48
  #50 (permalink)  
 
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Sunbirb123
Thats what went wrong in MEL, to my understanding.

Too many engineers with techlogs, fuelers with fuel slips, cabin crew with sandwiches and coffee groundstaff with bloody walkie talkies, dispatchers with load sheets with LMCs. All wanting the Captain attention and wanting an on time deaprture..

EK has changed since then, but still not very sterile. Engineers can fill out the log in silence and dont talk on mobile while doing it..
Send the fuel slip with the engineer
CC should stay away until called for.
I dont need to see the ground staff.
Let me sign the load sheet electronically

Now let get down to the business of briefing.....
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Old 10th Jul 2010, 06:27
  #51 (permalink)  
 
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Payscale:

AMEN
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Old 10th Jul 2010, 14:06
  #52 (permalink)  
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Sunbird123; (post #48)
I think that there are too many distractions in the modern cockpit.
Too many people coming in with papers to sign which breaks the routine of the crew. They then try to do more than one item at once to get back on schedule.
Data entry has always been a problem not just with airlines.
and,

Payscale; (post #53)
Thats what went wrong in MEL, to my understanding.

Too many engineers with techlogs, fuelers with fuel slips, cabin crew with sandwiches and coffee groundstaff with bloody walkie talkies, dispatchers with load sheets with LMCs. All wanting the Captain attention and wanting an on time deaprture..

EK has changed since then, but still not very sterile. Engineers can fill out the log in silence and dont talk on mobile while doing it..
Send the fuel slip with the engineer
CC should stay away until called for.
I dont need to see the ground staff.
Let me sign the load sheet electronically

Now let get down to the business of briefing.....
From the FARS:
(a) No certificate holder shall require, nor may any flight crew member perform any duties during a critical phase of flight except those duties required for the safe operation of the aircraft. Duties such as company required calls made for non-safety related purposes as ordering galley supplies and confirming passenger connections, announcements made to passengers promoting the air carrier or pointing out sights of interest and filling out company payroll and related records are not required for the safe operation of the aircraft.

(b) No flight crew member may engage in, nor may any pilot in command permit, any activity during a critical phase of flight which could distract any flight crew member from the performance of his or her duties or which could interfere in any way with the proper conduct of those duties. Activities such as eating meals, engaging in non-essential conversations within the cockpit and non-essential communications between the cabin and cockpit crews, and reading publications not related to the proper conduct of the flight are not required for the safe operation of the aircraft.

(c) For the purposes of this section, critical phase of flight involves all ground operations involving taxi, takeoff and landing, and all other flight operations conducted below 10,000 feet, except cruise flight.

Note: Taxi is defined as "movement of an airplane under its own power on the surface of an airport."
The decision to make the sterile cockpit on the ground a priority has already been partially made at some carriers. At a former company, it was policy that the F/A's did not interrupt the cockpit preparation until the time came for the briefing, which was signalled by the captain. Many times the briefing to the In-charge F/A took place in the cabin, prior to boarding the passengers and before cockpit preparation.

I don't think the same policy applied to maintenance, fueler, load-sheet acceptance, extra cockpit occupants such as regulatory (check) personnel, maintenance personnel (for test flights) etc. Each of these groups has their own time schedules and needs and usually have to be at other places quickly - those needs have been permitted to override the need for a undistracted cockpit preparation and have thus made our reaction to such interruptions almost automatically accomodating, - it is "part of the job of being an airline pilot to manage distraction", we are told. And to an extent, that is true. One key is necessity.

Most country's aviation regulations provide for some requirement for the sterile cockpit.

However, as indicated by the bolding Para (c), the rule does not apply in perhaps one of the most critical "phases" of flight, cockpit preparation for departure.

Here, the commercial priority of an on-time departure is privileged over the orderly preparation of the cockpit.

Constant interruptions such as MEL resolutions, F/A briefings/passenger issues) are permitted and supercede the need for the same sterility these regulations provide for in the air.

While the most important priority is the accurate preparation of the cockpit, commercial priorities are understandable as are the decisions from the captain on various dispatch matters which must be resolved prior to departure. The intent of any policy or regulatory provision and therefore future recurrent training regarding would be to provide for an orderly cockpit preparation without interruption, (from sitting down/adjusting seats and turning on the IRSs, to the completion of the takeoff briefing and including FMS entry of preliminary load data and the emergency briefing).

The objections and cited problems, and we can think of a number of them, will be based solely upon commercial and economic priorities, not flight safety priorities. Commercial priorities cannot be dismissed but must be instead accomodated. MEL items must be dealt with and sometimes they will even be a part of the cockpit preparation. Such issues must obviously be dealt with; the notion is "minimal distraction/interruption" - complete sterility is not likely possible.

At present, anyone with the need and who is not provided with at leasst some guidance regarding such cockpit interruptions, feels free to do so without further thought.

I doubt if some form of regulatory intervention would come about without strong airline lobbying but to my knowledge the issue has never been described or addressed in any formal way by any of the usual advocacy groups. Perhaps it is time?

PJ2
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Old 10th Jul 2010, 17:19
  #53 (permalink)  
 
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Milsabord

My guess is that the fact they were taking off from a very long runway at LHR with a lot of flat ground around may have had something to so with it. It could a been a very different result elsewhere.

Feeding in the wrong data is a very bad mistake and should have been caught. But the bit I find astonishing is that an experienced crew (Captain with over 16,000 hours) just watched the aircraft barely stagger into the air and didn't realise that something was (almost catastrophically) wrong. Why on earth did they not firewall (or TOGA or whatever it is called nowadays) the throttles? Are we in a situation that aircrew have so much trust or reliance or dependance on the computers that they are scared to over ride? As an ex pilot (DC-10, not Piper) and infrequent passenger I find that quite terrifying.
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Old 10th Jul 2010, 23:05
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Too many here do not know nowadays airline ops!

1. "time to V1" or alike: Airbus offers MFF as an integral part of the package. You can mix every type from A318 to A346, you derate/flex T/O power according to Wx and RWY (resulting in differing acceleration rates but similar weights), you even can flex a derated T/O, you fly maybe only 6-8 legs per month with approx. 1-2 legs as PF, and then somebody really expects the pilots flying to feel the correct acceleration or s.th.? Get real!

2. "sterile cockpit on ground": There's the rub! 40 minutes to prepare the a/c for the flight w/ 10 minutes before the SLF arrives, incl. outside check, tec log, booting the EFB and setting it to mode 2 and connecting and calibrating it, finding out why the wind data just won't load in the FMC, catching the bugs in the data bases (EFB/OFP/FMC), finding the difference between routing MUCCCU6 in the FMC and the routing MUCCCU6 in the OFP (or: hey, why is BGTL planned as an ETOPS alternate on Saturday), searching for the waypoint xyz13 from your flight plan to find that it has been renamed to zyx31 (on the 31st NOTAMs page) so you can find it in the FMC, now ordering missing meals from catering, a lavatory needs to be cleaned again, the flight control center wants to know why you stopped boarding so you have to call back (or have to decide not to) and explain that boarding while fueling with only one airstair is illegal (glad you caught that), now try to order a 2nd airstair, but the number is occupied (again), while you are listening in on the de-ice freq to catch the righ moment for your request (or reckon the right moment to ask for your airway clearance etc. etc.) - I give up. Does anybody who knows airline ops really wonder why pilots might miss s.th.? Really?
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Old 11th Jul 2010, 01:32
  #55 (permalink)  
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heavy.airborne;

If you read my post carefully, you will understand that I never stated that "sterile" on the ground would be easy or even doable - I said that it had never been addressed as it has while the aircraft is under way. I proposed some approaches because it is in this period that preparation errors can, as we have seen, lead to serious consequences and I acknowledged the problems with such solutions, which problems are primarily commercially driven as you have clearly demonstrated. "On time" is not a flight safety priority; "Ready" is. Commercial priorites are important and the balance between the two is achievable if it is managed well and supported with airline policy as I mentioned above. I am trying to open a dialogue here.

Why do you suppose this kind of error continues to occur and what's your proposal to resolve the issue?

I really don't know why I bother here anymore.

PJ2
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Old 11th Jul 2010, 06:16
  #56 (permalink)  
 
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heavy.airborne

Sounds like you need a Flight Engineer !

( glad I always had one )
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Old 11th Jul 2010, 06:28
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Too many tasks and distractions during Cockpit Preparation

HEAVY.AIRBORNE has provided just an average workload situation. There are too many tasks to accomplish, with many added due to computerization and electronic documentation.

2. "sterile cockpit on gound": There's the rub! 40 minutes to prepare the a/c for the flight w/ 10 minutes before the SLF arrives, incl. outside check, tec log, booting the EFB and setting it to mode 2 and connecting and calibrating it, finding out why the wind data just won't load in the FMC, catching the bugs in the data bases (EFB/OFP/FMC), finding the difference between routing MUCCCU6 in the FMC and the routing MUCCCU6 in the OFP (or: hey, why is BGTL planned as an ETOPS alternate on Saturday), searching for the waypoint xyz13 from your flight plan to find that it has been renamed to zyx31 (on the 31st NOTAMs page) so you can find it in the FMC, now ordering missing meals from catering, a lavatory needs to be cleaned again, the flight control center wants to know why you stopped boarding so you have to call back (or have to decide not to) and explain that boarding while fueling with only one airstair is illegal (glad you caught that), now try to order a 2nd airstair, but the number is occupied (again), while you are listening in on the de-ice freq to catch the righ moment for your request (or reckon the right moment to ask for your airway clearance etc. etc.) - I give up. Does anybody who knows airline ops really wonder why pilots might miss s.th.? Really?
To achieve an ONTIME departure there has to be a certain degree of short cuts. Accomplishing the above in 40 mins is impossible! Unfortunately added to this is a checklist which many crews just pay lip service to, i.e. checked, checked, checked, but actually not Xchecking the parameters correctly.

The checklist read and challenge procedure needs to be modified to avoid this lip service. For example the replier should nominate or state a setting/number and the reader should then also state the setting/number too and then say Xchecked for each checklist item.
This is the last line of defence!
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Old 11th Jul 2010, 07:00
  #58 (permalink)  
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Capt. Groper;
To achieve an ONTIME departure there has to be a certain degree of short cuts.
We complain at times about management's parsimony in terms of safety but here is an area where we can have direct effect on ensuring an appropriate level of safety commensurate with commercial considerations. I say again, "On time" is not a flight safety priority; "Ready" is. I am fully cognizant of all the issues, distractions, demands upon attention which are stated by heavy.airbourne. BTDT many, many times but it is not an excuse for error, it is a reason for error.

I am fully aware of the demands made upon us by all and sundry during departure preps and have had to deal with most if not all of the issues outlined in the post at one time or another in a 35-year career starting with the DC9 and ending eight types later on the A330/A340. I am fully aware of calls from one's superiors about a late departure and the pressure to push back from everyone. But that certainly isn't the point here - the captain is the captain and can manage and direct actions, resources and priorities.

The point is, a sterile cockpit is a legal requirement after pushback; what about considering such during another critical phase of flight, cockpit preparation?

The only resistance to this idea seems to come from those who still put up with all the demands made by others in their cockpit and who consider on-time performance a mandatory requirement, when in fact it is not - it is a commercial requirement.

That doesn't mean one beligerantly ignores one's commercial responsibilities towards one's employer, nothing of the sort - this is a rational call for an examination of the question, including the question about why FMS entries continue to be a source of potential takeoff accidents.

PJ2

Last edited by PJ2; 11th Jul 2010 at 07:12.
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Old 11th Jul 2010, 07:55
  #59 (permalink)  
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PJ - I think I know you well enough to know that while this is an admirable target, you, especially after your time 'in the business' must recognise that it is unachievable in the world in which we live - akin to asking someone to move Mount Everest 2135m to the south.

Heavy has summed it up precisely. We have a very experienced and no doubt extremely capable Captain, as F/O, experiencing the familiar snowball effect. We all know how feeble it is when asked why you were 10 minutes late on pushback when the dispatcher said 'all was ready' (don't forget his 'on-time' bonus), and you try to explain the small discrepancy on the fuel uplift, the late toilet truck (F/O on radio trying to sort it) c/crew with a drunken pax, not enough orange juice - and then a new load sheet after all the prep is done - and not one of your immediate managers can understand why you got a bit screwed up. Their actions after brakes off on the runway may well bear scrutiny by the company but to change the 'day in the life' of a crew before push-back requires a total re-write of the way commercial aviation is done. Even if we adopt the US style of dispatcher here and off-load ALL non-flight orientated stuff to them, who is going to make the command decisions that inevitably crop up and will affect the actual flight once you have left the tower of babel?

I think the only solution is to get a major shift away from this paranoia of 'on-time' departures (with all the ensuing problems for slots/stands etc) and lift some of the pressures. Back to Mount Everest?
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Old 11th Jul 2010, 09:17
  #60 (permalink)  
 
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Discorde,
Is this the kit you were referring to?



Should have carried Loadies - They never make mistakes!!


C o' G
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