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FlyingJhawk
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AC 737 MAX Weight Imbalance Incidents

Fri Jan 07, 2022 7:43 pm

I didn't see this posted here. Looks like two separate incidents with AC at two different airports. How often does this happen and is it a bit more "newsworthy" because it a MAX?

https://www.flightglobal.com/safety/det ... 38.article
 
737MAX7
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Re: AC 737 MAX Weight Imbalance Incidents

Fri Jan 07, 2022 7:53 pm

FlyingJhawk wrote:
I didn't see this posted here. Looks like two separate incidents with AC at two different airports. How often does this happen and is it a bit more "newsworthy" because it a MAX?

https://www.flightglobal.com/safety/det ... 38.article

It happens more than you’d think. Only newsworthy because they are MAX’s. Had a ferry flight one time show up with 140 bags on it that were still supposed to be at PIT.
 
kaitak
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Re: AC 737 MAX Weight Imbalance Incidents

Fri Jan 07, 2022 8:15 pm

Sounds very much like a dispatcher error; its his/her job to make sure that the payload goes where it's supposed to go and feed that information in to generate a loadsheet.

I don't know what system AC uses, though I'm sure it's automated, for an airline of that size. They will have a central load control team (CLC) who will generate an LIR (load instruction report); it's the dispatcher's job to ensure that load is put where it should be and then, when the head loader comes back with the LIR properly completed (saying where the bags are and how many), he/she will enter that into a system which will generate a loadsheet. As the saying goes - GIGO ... garbage in, garbage out. The load is planned by CLC to produce the optimum MACTOW, to ensure that the aircraft is trimmed, primarily for safety and secondly, for economics. BUT, if the information going in is wrong, the aircraft will not be trimmed properly and that has the result you see with the AC flights.

It can be extremely dangerous and it wouldn't be a surprise if the dispatcher was asked to consider a different career ...

Here's an example of a report where things were done incorrectly, on an ATR72: http://www.aaiu.ie/sites/default/files/ ... -002_0.pdf
 
777luver
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Re: AC 737 MAX Weight Imbalance Incidents

Fri Jan 07, 2022 9:26 pm

kaitak wrote:
Sounds very much like a dispatcher error; its his/her job to make sure that the payload goes where it's supposed to go and feed that information in to generate a loadsheet.

I don't know what system AC uses, though I'm sure it's automated, for an airline of that size. They will have a central load control team (CLC) who will generate an LIR (load instruction report); it's the dispatcher's job to ensure that load is put where it should be and then, when the head loader comes back with the LIR properly completed (saying where the bags are and how many), he/she will enter that into a system which will generate a loadsheet. As the saying goes - GIGO ... garbage in, garbage out. The load is planned by CLC to produce the optimum MACTOW, to ensure that the aircraft is trimmed, primarily for safety and secondly, for economics. BUT, if the information going in is wrong, the aircraft will not be trimmed properly and that has the result you see with the AC flights.

It can be extremely dangerous and it wouldn't be a surprise if the dispatcher was asked to consider a different career ...

Here's an example of a report where things were done incorrectly, on an ATR72: http://www.aaiu.ie/sites/default/files/ ... -002_0.pdf


At AC they are called Lead Station Attendants. It's hard to mess up a loadsheet instruction though. You simply follow the instructions and load it, then do as you stated. It's a big responsibility and I'm sure someone is getting a talking to
 
rampbro
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Re: AC 737 MAX Weight Imbalance Incidents

Fri Jan 07, 2022 9:59 pm

777luver wrote:
kaitak wrote:
Sounds very much like a dispatcher error; its his/her job to make sure that the payload goes where it's supposed to go and feed that information in to generate a loadsheet.

I don't know what system AC uses, though I'm sure it's automated, for an airline of that size. They will have a central load control team (CLC) who will generate an LIR (load instruction report); it's the dispatcher's job to ensure that load is put where it should be and then, when the head loader comes back with the LIR properly completed (saying where the bags are and how many), he/she will enter that into a system which will generate a loadsheet. As the saying goes - GIGO ... garbage in, garbage out. The load is planned by CLC to produce the optimum MACTOW, to ensure that the aircraft is trimmed, primarily for safety and secondly, for economics. BUT, if the information going in is wrong, the aircraft will not be trimmed properly and that has the result you see with the AC flights.

It can be extremely dangerous and it wouldn't be a surprise if the dispatcher was asked to consider a different career ...

Here's an example of a report where things were done incorrectly, on an ATR72: http://www.aaiu.ie/sites/default/files/ ... -002_0.pdf


At AC they are called Lead Station Attendants. It's hard to mess up a loadsheet instruction though. You simply follow the instructions and load it, then do as you stated. It's a big responsibility and I'm sure someone is getting a talking to


100%. You don't accidentally put all the bags in the front. Sometimes the estimates are wrong and there's way more or fewer bags. Given the fact they only loaded the front, likely the latter in this case. Go talk to the pilot or call Ops.
Does AC have it's own rampers at LAX or does it use a contractor? I should probably give myself three guesses on that and the first two don't count.
 
777luver
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Re: AC 737 MAX Weight Imbalance Incidents

Fri Jan 07, 2022 10:24 pm

rampbro wrote:
777luver wrote:
kaitak wrote:
Sounds very much like a dispatcher error; its his/her job to make sure that the payload goes where it's supposed to go and feed that information in to generate a loadsheet.

I don't know what system AC uses, though I'm sure it's automated, for an airline of that size. They will have a central load control team (CLC) who will generate an LIR (load instruction report); it's the dispatcher's job to ensure that load is put where it should be and then, when the head loader comes back with the LIR properly completed (saying where the bags are and how many), he/she will enter that into a system which will generate a loadsheet. As the saying goes - GIGO ... garbage in, garbage out. The load is planned by CLC to produce the optimum MACTOW, to ensure that the aircraft is trimmed, primarily for safety and secondly, for economics. BUT, if the information going in is wrong, the aircraft will not be trimmed properly and that has the result you see with the AC flights.

It can be extremely dangerous and it wouldn't be a surprise if the dispatcher was asked to consider a different career ...

Here's an example of a report where things were done incorrectly, on an ATR72: http://www.aaiu.ie/sites/default/files/ ... -002_0.pdf


At AC they are called Lead Station Attendants. It's hard to mess up a loadsheet instruction though. You simply follow the instructions and load it, then do as you stated. It's a big responsibility and I'm sure someone is getting a talking to


100%. You don't accidentally put all the bags in the front. Sometimes the estimates are wrong and there's way more or fewer bags. Given the fact they only loaded the front, likely the latter in this case. Go talk to the pilot or call Ops.
Does AC have it's own rampers at LAX or does it use a contractor? I should probably give myself three guesses on that and the first two don't count.


Exactly. I think AC contracts out LAX. Still, you have to call load and verify the loading instructions
 
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LAXintl
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Re: AC 737 MAX Weight Imbalance Incidents

Fri Jan 07, 2022 10:29 pm

Hardly a MAX issue. If any aircraft is not loaded within planned perimeters, you can end up in all types of situations from tail tipping at the gate to loss of control inflight.

And yes, AC contracts out underwing at LAX.
 
planecane
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Re: AC 737 MAX Weight Imbalance Incidents

Fri Jan 07, 2022 10:47 pm

737MAX7 wrote:
FlyingJhawk wrote:
I didn't see this posted here. Looks like two separate incidents with AC at two different airports. How often does this happen and is it a bit more "newsworthy" because it a MAX?

https://www.flightglobal.com/safety/det ... 38.article

It happens more than you’d think. Only newsworthy because they are MAX’s. Had a ferry flight one time show up with 140 bags on it that were still supposed to be at PIT.


I would think that this should be newsworthy no matter what aircraft it is. It is more than slightly concerning to me that it happens more than I would think as if it is far enough off it can end up in a disaster.
 
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Sig56
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Re: AC 737 MAX Weight Imbalance Incidents

Fri Jan 07, 2022 11:03 pm

rampbro wrote:
777luver wrote:
kaitak wrote:
Sounds very much like a dispatcher error; its his/her job to make sure that the payload goes where it's supposed to go and feed that information in to generate a loadsheet.

I don't know what system AC uses, though I'm sure it's automated, for an airline of that size. They will have a central load control team (CLC) who will generate an LIR (load instruction report); it's the dispatcher's job to ensure that load is put where it should be and then, when the head loader comes back with the LIR properly completed (saying where the bags are and how many), he/she will enter that into a system which will generate a loadsheet. As the saying goes - GIGO ... garbage in, garbage out. The load is planned by CLC to produce the optimum MACTOW, to ensure that the aircraft is trimmed, primarily for safety and secondly, for economics. BUT, if the information going in is wrong, the aircraft will not be trimmed properly and that has the result you see with the AC flights.

It can be extremely dangerous and it wouldn't be a surprise if the dispatcher was asked to consider a different career ...

Here's an example of a report where things were done incorrectly, on an ATR72: http://www.aaiu.ie/sites/default/files/ ... -002_0.pdf


At AC they are called Lead Station Attendants. It's hard to mess up a loadsheet instruction though. You simply follow the instructions and load it, then do as you stated. It's a big responsibility and I'm sure someone is getting a talking to


100%. You don't accidentally put all the bags in the front. Sometimes the estimates are wrong and there's way more or fewer bags. Given the fact they only loaded the front, likely the latter in this case. Go talk to the pilot or call Ops.
Does AC have it's own rampers at LAX or does it use a contractor? I should probably give myself three guesses on that and the first two don't count.

AC is handled by ATS in LAX. I believe they also handle them in SEA.
 
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Exrampieyyz
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Re: AC 737 MAX Weight Imbalance Incidents

Sat Jan 08, 2022 2:09 am

Worked on the ramp for over 30 years and saw quite a few "Cat G" incidents. (Never found out why they called it that). A Cat G was when the flight left with a load discrepancy (I think) of more than 500lbs or some certain percentage of MAC (mean aerodynamic chord) error. Meant some sort of disciplinary action. A "Cat i" was a lessor error.
I once parked a Dash 8 and the Capt. came back and asked me to count the bags as I off loaded. ( We always count out bound but never inbound). Seemed the auto pilot wouldn't stay engauged because it couldn't feed in enough nose down trim. They had to hand fly pushing on the yoke the whole flight. YSB - YYZ about an hour.
Another time LHR couldn't find a pallet that we loaded on the upper deck of a 747-233 SCD Combi. My Lead was looking at disciplinary action, but asked, well if we didn't send it what did we send because the flight never went out with empty positions. Again we never checked inbound pallet numbers, but he drove out to where we dropped off the inbound pallets and found it sitting there. LHR had off loaded that pallet and then had re-boarded it by mistake back to YYZ.
Never worked a MAX but pretty hard to load the wrong compartments on a non container flight. Maybe miscounting but the load sheet is pretty simple. DC-9s and 727s were usually nose heavy full of people so aft compartments where loaded first and the load sheet would look something like this.

C1 nil

C2 overflow

Wing

C3 2nd/80 bags

C4 1st/32 bags

Pretty hard to misinterpit that!!
 
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theAviationGeek
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Re: AC 737 MAX Weight Imbalance Incidents

Sat Jan 08, 2022 4:10 am

Exrampieyyz wrote:
Worked on the ramp for over 30 years and saw quite a few "Cat G" incidents. (Never found out why they called it that). A Cat G was when the flight left with a load discrepancy (I think) of more than 500lbs or some certain percentage of MAC (mean aerodynamic chord) error.



“Cat G”, rather clever given its dealing with CG issues.

Ryan
 
smi0006
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Re: AC 737 MAX Weight Imbalance Incidents

Sat Jan 08, 2022 5:50 am

Exrampieyyz wrote:
Worked on the ramp for over 30 years and saw quite a few "Cat G" incidents. (Never found out why they called it that). A Cat G was when the flight left with a load discrepancy (I think) of more than 500lbs or some certain percentage of MAC (mean aerodynamic chord) error. Meant some sort of disciplinary action. A "Cat i" was a lessor error.
I once parked a Dash 8 and the Capt. came back and asked me to count the bags as I off loaded. ( We always count out bound but never inbound). Seemed the auto pilot wouldn't stay engauged because it couldn't feed in enough nose down trim. They had to hand fly pushing on the yoke the whole flight. YSB - YYZ about an hour.
Another time LHR couldn't find a pallet that we loaded on the upper deck of a 747-233 SCD Combi. My Lead was looking at disciplinary action, but asked, well if we didn't send it what did we send because the flight never went out with empty positions. Again we never checked inbound pallet numbers, but he drove out to where we dropped off the inbound pallets and found it sitting there. LHR had off loaded that pallet and then had re-boarded it by mistake back to YYZ.
Never worked a MAX but pretty hard to load the wrong compartments on a non container flight. Maybe miscounting but the load sheet is pretty simple in. DC-9s and 727s were usually nose heavy full of people so aft compartments where loaded first and the load sheet would look something like this.

C1 nil

C2 overflow

Wing

C3 2nd/80 bags

C4 1st/32 bags

Pretty hard to misinterpit that!!


I think these types of errors are going to become a serious risk - everyone focuses on cabin and tech crew resourcing at the moment, I think ramp resourcing is more dangerous. It’s clearly obvious when 1/2 crew short and a simple no go/go depending on Union/regulatory requirements. What’s harder to see is the impact of ramp agents pushed too hard, across off schedule departures, short staff due to sickness and trying to supervise multiple departures. Especially tricky for handling companies try to support multiple client carriers - often with very demanding station staff.

At a guess, potential plausibility options - ramp leading hand (my airlines title, not sure AC) was supervising two or more flights due to staff shortage, with disruptions etc short staffed, got focused on an issue at one turn and didn’t physical supervise the loading of the rear hold. Asked one of his team if it had been correctly loaded - who misunderstood, or misheard, and incorrectly confirmed it had and they confirmed the LIR with CLC.

Most likely the agent was trying to do the best he could with the resources to get the client, passengers and crew away with minimal impact and wasn’t intentionally negligent.
 
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golfradio
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AC - two load imbalance incidents in short span

Sun Jan 09, 2022 2:25 am

There were two recent load imbalance incidents with AC flights. The first one on Dec 19th, YVR - YEG and the second on Jan 3rd LAX - YVR. First was nose light and second was nose heavy.

https://avherald.com/h?article=4f25c6fb&opt=0
https://avherald.com/h?article=4f2c0bab&opt=0

Recollecting the National 102 crash at Bagram, load shift is a serious issue. I know these two incidents are not really the same as the N8102 incident, but how serious are these load imbalance incidents in commercial passenger ops?
 
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zeke
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Re: AC - two load imbalance incidents in short span

Sun Jan 09, 2022 2:43 am

I don’t have the facts before me it is possible in both cases the aircraft was within the normal CG band.

What would have been out was the stabiliser setting for takeoff with the resulting unusual control feel.
 
kalvado
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Re: AC - two load imbalance incidents in short span

Sun Jan 09, 2022 5:05 pm

zeke wrote:
I don’t have the facts before me it is possible in both cases the aircraft was within the normal CG band.

What would have been out was the stabiliser setting for takeoff with the resulting unusual control feel.

AH quote 5.8% for LAX flight. I cannot find data for MAX, but looks like this is a bit out of limit for non-max 738 takeoff. If I interpreted things correctly, of course.

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