ASA weight and balance
12-21-2007, 07:53 AM
#1
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Joined APC: Jan 2006
Position: MD80 Left
Posts: 45
ASA weight and balance
Im a new FO and I ran into an issue the other day that ended up costing an hour delay. I'm pretty sure this is a big issue as far as ASA's on time performance.
We often get hit up with the "how many people can we take" line, and that is a fairly easy calculation that doesnt result in aircraft balance issues because bags go before pax. This particular flight, however, was downgraded from a 700 to 200 (no clue why), so it was important to delta that that pax go before the bags. That is an easy calculation as well, but it will most often result in balance issues because there is no junk in the trunk. You can't throw balast in the back becasue you are already at max weight, so you end up kicking more people off the plane and adding bags to balance things out.
Im not sure why, but no body on the ramp seems to understand the whole balance concept either.
I guess my question would be, has anyone developed software or a spread sheet that allows you to input all these variables and come out with a quick number to tell the agent that will result in an under max, balanced condition?
We often get hit up with the "how many people can we take" line, and that is a fairly easy calculation that doesnt result in aircraft balance issues because bags go before pax. This particular flight, however, was downgraded from a 700 to 200 (no clue why), so it was important to delta that that pax go before the bags. That is an easy calculation as well, but it will most often result in balance issues because there is no junk in the trunk. You can't throw balast in the back becasue you are already at max weight, so you end up kicking more people off the plane and adding bags to balance things out.
Im not sure why, but no body on the ramp seems to understand the whole balance concept either.
I guess my question would be, has anyone developed software or a spread sheet that allows you to input all these variables and come out with a quick number to tell the agent that will result in an under max, balanced condition?
12-21-2007, 07:58 AM
#2
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Joined APC: Apr 2007
Posts: 3,814
Most rampers barely have a GED, let alone a high-school education...it's not worth your time to explain to them the concept of W&B.
My guess is that a rough, generic spreadsheet could easily be generated using average aircraft weights...but since every aircraft is unique in the W&B department, the figures wouldn't be exact...
My guess is that a rough, generic spreadsheet could easily be generated using average aircraft weights...but since every aircraft is unique in the W&B department, the figures wouldn't be exact...
12-21-2007, 08:16 AM
#3
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Posts: 45
re
bow, mtow, pax(winter, summer), bags(standard, heavy, valet), fuel. Pretty much every thing that is blank on the load manifest would have to be a variable, and I wouldn't even know how to begin programming the cg calculator. The end result would ideally be a program that would tell you either you are good, or add bags, take off pax, or whatever.
12-21-2007, 08:22 AM
#4
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Joined APC: Mar 2007
Posts: 114
Most rampers barely have a GED, let alone a high-school education...it's not worth your time to explain to them the concept of W&B.
My guess is that a rough, generic spreadsheet could easily be generated using average aircraft weights...but since every aircraft is unique in the W&B department, the figures wouldn't be exact...
My guess is that a rough, generic spreadsheet could easily be generated using average aircraft weights...but since every aircraft is unique in the W&B department, the figures wouldn't be exact...
12-21-2007, 08:24 AM
#6
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Joined APC: Apr 2007
Posts: 3,814
I have been a CSA as well...worked the Ramp, the Gate, Check-In, Ticketing, Customs CS, you name it. I'm speaking from first-hand experience. But you're right - some are sharp as nails. Unfortunately, they are just the vast minority. The pay isn't good enough to attract more qualified applicants.
12-21-2007, 08:29 AM
#7
Gets Weekends Off
Joined APC: Mar 2007
Posts: 114
I have been a CSA as well...worked the Ramp, the Gate, Check-In, Ticketing, Customs CS, you name it. I'm speaking from first-hand experience. But you're right - some are sharp as nails. Unfortunately, they are just the vast minority. The pay isn't good enough to attract more qualified applicants.
12-21-2007, 10:50 AM
#10
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Joined APC: Apr 2007
Position: E170 FO
Posts: 686
I don't remember them off the top of my head, but there are some weight shift calculation in your basic flight textbooks. Eventually, you just get a feel for what will work and what won't so that you don't have to do too much trial and error to fine tune it.
A spreadsheet wouldn't be hard to do. You just need the index and weight at each index. Then do the standard force*arm =moment. Sum up all the moments and divide by the total weight to get the CG arm. Its gets more complicated in jets that are index based b/c you need to know what the index baseline is. If you want it to magically just give you green for good and red for bad, you'd also need to program in the envelope. Basics, easy to do. To just give you an answer like an FMS, much harder. Also, not everyone's FMS's and ACARS do W&B calcs for us. I still do W&B and CG calcs with paper and a whiz wheel.
A spreadsheet wouldn't be hard to do. You just need the index and weight at each index. Then do the standard force*arm =moment. Sum up all the moments and divide by the total weight to get the CG arm. Its gets more complicated in jets that are index based b/c you need to know what the index baseline is. If you want it to magically just give you green for good and red for bad, you'd also need to program in the envelope. Basics, easy to do. To just give you an answer like an FMS, much harder. Also, not everyone's FMS's and ACARS do W&B calcs for us. I still do W&B and CG calcs with paper and a whiz wheel.
