manual loadsheet help
Joined: Mar 2009
Posts: 4
Likes: 0
From: scotland
I have to agree with you Schibulsky and SMT member, some of the questions being posted are very concerning.
I run my own company and have been producing manual loading systems for all types of aircraft and I can say that each operator, type of operation, company ground ops procedures, A/c manufacturer, type, model, fuel tank configuration and interior configuration will have a massive impact on what type of trimsheet is produced and how the curtailed flight envelope limits are derived.
This is just the start as you then have to ensure that graphically the trimsheet is presentable, easily populated and produces acurate results for take-off landing etc.
I agree that there are a lot of half trained people out there producing W&B docs thinking that they know what they are doing is correct.
The other issue is that by using other trimsheets as examples to base your trimsheet on is not good practice unless you have the full substantiating data/report that the trimsheet was derived from. That way you can acuratly determine if the trimsheet is accurate and can be used for the basis of your calculations or for reference.
If and when you produce a new trimsheet for your aircraft and if there are any errors within it. It may also end up in someone elses hands being used an example of how to produce their trimsheet and even worse, actually used for their operation. I have known for this to happen with more than one airline.
Anyway, If I can be of any further assistance to you, then please contact me on [email protected]
I run my own company and have been producing manual loading systems for all types of aircraft and I can say that each operator, type of operation, company ground ops procedures, A/c manufacturer, type, model, fuel tank configuration and interior configuration will have a massive impact on what type of trimsheet is produced and how the curtailed flight envelope limits are derived.
This is just the start as you then have to ensure that graphically the trimsheet is presentable, easily populated and produces acurate results for take-off landing etc.
I agree that there are a lot of half trained people out there producing W&B docs thinking that they know what they are doing is correct.
The other issue is that by using other trimsheets as examples to base your trimsheet on is not good practice unless you have the full substantiating data/report that the trimsheet was derived from. That way you can acuratly determine if the trimsheet is accurate and can be used for the basis of your calculations or for reference.
If and when you produce a new trimsheet for your aircraft and if there are any errors within it. It may also end up in someone elses hands being used an example of how to produce their trimsheet and even worse, actually used for their operation. I have known for this to happen with more than one airline.
Anyway, If I can be of any further assistance to you, then please contact me on [email protected]
Joined: Jun 2012
Posts: 20
Likes: 0
From: wild blue yonder
Manual Load Chart/Sheet A320
Anyone know why?
On the right side of the chart/sheet where the I.U. is adjusted we first bring the line down from the top, through the pax for zones A, B, and C then the cargo/freight for CP/cargo bays 1,2,3,4, and 5.
Question is:
Why then as we drop down to further adjust for the fuel do the lines go all funny? I mean that rather than continuing to be straight they then become curved?
Any answers?
On the right side of the chart/sheet where the I.U. is adjusted we first bring the line down from the top, through the pax for zones A, B, and C then the cargo/freight for CP/cargo bays 1,2,3,4, and 5.
Question is:
Why then as we drop down to further adjust for the fuel do the lines go all funny? I mean that rather than continuing to be straight they then become curved?
Any answers?
Joined: Oct 2008
Posts: 46
Likes: 0
From: Europe
I agree with the comments above a lot of these questions are very concerning, however it wouldn't surprise me if staff in CLC centres around the world do their training this way.
The lack of confidence in a lot of these guys is frightening it is almost like dealing with call centres where people read off a script, that is why the actual job of load control is / has been diluted, I recall completing re trimming at A/C side due to stop issues on a B747-400 whilst doing a manual load sheet, nowadays someone stands at the Aircraft makes a call and asks to swap 2 bins and gets told no.
Still that's progress I guess airlines like it that way and there is minimal training required at either end.
The lack of confidence in a lot of these guys is frightening it is almost like dealing with call centres where people read off a script, that is why the actual job of load control is / has been diluted, I recall completing re trimming at A/C side due to stop issues on a B747-400 whilst doing a manual load sheet, nowadays someone stands at the Aircraft makes a call and asks to swap 2 bins and gets told no.
Still that's progress I guess airlines like it that way and there is minimal training required at either end.
Joined: May 2013
Posts: 1
Likes: 0
From: australia
Dog star,
Think of the effect of fuelling the aircraft. As the fuel fills in the wings(747-400)The fuel effect takes the fuel vector along way forward up to 125,000kg. After this the tail tank comes into play and as it fills at a ratio of 1kgaft/9fwd approx., the trim effect moves aft.
So much so that at MTOW 397210kg approx., if a/c is too tail heavy at ZFW a fuel change of 100kg in the tail tank will put a/c out of trim at TOW.
The shape of the lines reflects the way the fuel travels/fills the wings during fuelling. Except for non standard fuelling scenarios.
Think of the effect of fuelling the aircraft. As the fuel fills in the wings(747-400)The fuel effect takes the fuel vector along way forward up to 125,000kg. After this the tail tank comes into play and as it fills at a ratio of 1kgaft/9fwd approx., the trim effect moves aft.
So much so that at MTOW 397210kg approx., if a/c is too tail heavy at ZFW a fuel change of 100kg in the tail tank will put a/c out of trim at TOW.
The shape of the lines reflects the way the fuel travels/fills the wings during fuelling. Except for non standard fuelling scenarios.
Fleet Manager
Joined: Apr 2001
Aviation Qualifications: ATPL
Posts: 7,441
Likes: 306
From: various places .....
Or, to summarise pinarelloman's post (in italics)
(a) curved lines against a particular load indicate that the load's mean CG varies with the load - most commonly seen with non-prismatic fuel tanks.
For smaller aircraft the designer often approximates varying CG to a constant CG, taking out the error by tweaking the envelope limits. For larger aircraft, especially swept wing, this is not feasible hence you get the actual CG story. Several ways to approach the problem but all have the same result for the calculations ..
It is worth noting that, on occasion, you will see curved lines other than for a load position. Generally, this will occur for aircraft with widely disparate ZFW and in-flight envelopes. Examples are the GII and, if my recollection is correct, the HS125 (although the latter generally doesn't warrant a trimsheet). If this is the situation, there will be a strange-looking grid between the final ZFW trimline and the fuel line(s) ... or the fuel trim can be incorporated into that grid.
Reason, in this case, is to re-scale and then relocate the re-scaled IU scale .. it sounds more complicated than it really is ..
First one of these for which I had to design a sheet (GII 35-odd years ago) caused me a headache until I got my head around that point ...
(b) straight lines (or the simpler tick approach) indicate a constant CG with varying load
.. have to agree with a number of comments/concerns above relating to the oft-seen poor level of understanding on the line and in the backroom ..
(a) curved lines against a particular load indicate that the load's mean CG varies with the load - most commonly seen with non-prismatic fuel tanks.
For smaller aircraft the designer often approximates varying CG to a constant CG, taking out the error by tweaking the envelope limits. For larger aircraft, especially swept wing, this is not feasible hence you get the actual CG story. Several ways to approach the problem but all have the same result for the calculations ..
It is worth noting that, on occasion, you will see curved lines other than for a load position. Generally, this will occur for aircraft with widely disparate ZFW and in-flight envelopes. Examples are the GII and, if my recollection is correct, the HS125 (although the latter generally doesn't warrant a trimsheet). If this is the situation, there will be a strange-looking grid between the final ZFW trimline and the fuel line(s) ... or the fuel trim can be incorporated into that grid.
Reason, in this case, is to re-scale and then relocate the re-scaled IU scale .. it sounds more complicated than it really is ..
First one of these for which I had to design a sheet (GII 35-odd years ago) caused me a headache until I got my head around that point ...
(b) straight lines (or the simpler tick approach) indicate a constant CG with varying load
.. have to agree with a number of comments/concerns above relating to the oft-seen poor level of understanding on the line and in the backroom ..
