AIrline pilots and loading charts

Aussie

Aussie

New Member
Last night, i was studing the Loading chart Echo for my Commercial pilots license, and this thought came to mind.
"How do Airline pilots check to find their TOW ZFW, weather aircraft is in balance, Centre of Gravity ect.

In light aircraft we use Loading charts A,B,C and Echo for the CPL, what about Airline pilots? Even regionals whould surely have a different way? Is it the Flight Management System?

Any help appreciated!!

Aussie
 
I think every airline does it differently. Here's how it's done at SWA. There is this big long sheet of paper that the Operations agents writes the number of pax (adults and children is need be), the amount of fuel, how many bags, and where the bags are loaded (front or rear). Flip the sheet over, and it has the stats for the weight/moment. Add everything in the columns and make sure your results don't overgross the plane. It is VERY VERY VERY difficult to load a 737 out of CG limits, especially the -700 series. We've tried. Numerous times. There's another chart that converts your CG into stab trim settings, and the pilots use this to set the horizontal stabilizer. The only problems I've had are overgrossing the aircraft. Sometimes all it takes is to count the number of kids on the plane, and make sure you have them down as children weights instead of adults. If that doesn't work, it's time to start pulling cargo. Freight comes off first, then bags, then mail. I know mail as a higher priority than bags is kinda weird, but it has something to do with our new mail contract.
 
Well, while I'm not yet qualified to speak on the matter (my FAA practical dest for my dispatcher ticket is Tuesday...
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), it's actually done on a computer most of the time in the real world....
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.

We've done it on the 727 basically the same way it's done in a 152...but we convert it to % of MAC (whole different subject entirely...).
 
For us, we have two ways to do it: Manual, or OBD (on-board dispatch). Manual is on a large load sheet. We have the BOW (basic operating weight), and the basic index (CG/MAC). The basic index is used for the See-Gee calculator we have, which is one big whizz wheel used for CG calculations. Basically move an index mark, and it moves the whole thing to give you your operating index and trim setting for weight. On the load sheet you must add up all the values (fuel, pax in each section, bags in each bin, etc.) and come up with ramp, takeoff, and landing weights. To finish it up, you break out the takeoff data books and look up the takeoff speeds, power settings, restricted weights, etc. for your runway. Long process.

The easier way is the OBD computer. It's a weight and balance/performance computer, where you put in the departure/arrival/alternate weather, runway, etc., bags, passengers, fuel, fuel burn, aircraft configuration, and it puts out all the numbers. Speeds, power settings, acceleration altitude, restricted weights, trim settings, and so on. Much simpler than the manual way, but it's good to stay current on how to do manual since the OBDs often get all jacked up somehow and you have to go back "old school."
 
Aussie, each aircraft has a different load sheet with a different CoG. The loading system you are using for your CPL exams is basically a generic system loosely based on a Navajo I think.

In the B1900, we have to account for weight in each row of seats, weight in the nose locker and aft cargo compartments, fuel etc...
The crew prepares the trim sheet manually prior to departure as soon as we have closed the flight and have pax and baggage weights to tally. We use standard weights for pax (84kgs male and 69kg female) and allow for 5kg of carry on, but we get exact weights for checked in baggage.


As for your studies... it gets harder with ATPL subjects unfortunately... The flight planning and weight/balance exams are a royal pain in the arse (both B727 based, with systems based on the B767), I highly recommend getting the 7 ATPL subjects done as early in your career as possible... aint much fun!
 
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It is VERY VERY VERY difficult to load a 737 out of CG limits, especially the -700 series. We've tried. Numerous times.

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Why would you try to do this?
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Gday Mate, how you been? Long time no see!

Thanks for that. So what your saying is, I will most likely only use the A,B,C,E charts on my exams, and then each a/c i fly will have its own individual chart? They must be similar though?
How long does it take you to work through the loading chart, CoG ect? DO you do that just before engine start?

ATPL, did you do yours straight up? I heard its best tot get them out of the way. What would you recommend? I heard you can do a 7week Tafe course to get your ATPL, or study at home? I heard its alittle too much for study at home...
How did you do yours?
What are the 7 subjects?

Cheers

Aussie
 
Hey Aussie, been busy lately which is a nice change!

The load charts you are using for CPL exams etc will give you a good education on the general use of basic load charts. But yes, each aircraft is different.

I did my ATPL subjects through correspondance. Would NOT recommend it. I used Advanced Flight Theory and they were fantastic, do the full time course if you can, 3 weeks on the Gold Coast is one of the better places to be stuck for 3 weeks!
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Avoid TAFE courses if you can, they give you an OK background to it all, but its not structured as good as the privately run courses.

Do the subjects before you start working in the industry if you can, I did mine while I was doing 100hrs flying a month and the majority of that was night freight... not a great combination but somehow I got through it all.

Cheers
 
[ QUOTE ]

It is VERY VERY VERY difficult to load a 737 out of CG limits, especially the -700 series. We've tried. Numerous times.


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Why would you try to do this?

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Sometimes on originators, we get the bags, freight, etc like two hours before departure. We get bored and load the plane backwards to see if (according to the paperwork) it's out of trim. We would NEVER let it take off that way. I have never seen a -700 knocked out of CG (even with close to 5000 lbs of freight in the wrong end of the plane), but a -300 is easy to load incorrectly. There are sometimes it's loaded right and it's out of trim. Then it's time to start pulling stuff off.
 
>>The only problems I've had are overgrossing the aircraft<<

I'm trying to figure out how SWA and ATA haul big loads on long legs out of MDW. When I try to go just MDW to ATL we are either light on gas or limiting pax and cargo, expecially in the summer.

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I fly the SAAB like FlyChicaga. Unfortunately, my airline doesn't have the fancy OBD. We do it manually.

Our release has the runway data for the departure and arrival airports. We look up the runway we're taking off and go over to the temperature and we get our runway/climb limit weight. Normally it is over Max. Gross of the aircraft so we're rarely runway limited (except in DCA on the short runway). That data is entered onto our load form. We then take the BOW and Index of the aircraft (also on the release), enter that, the fuel onboard, the taxi and fuel burns. Then we wait.

5 minutes before departure, we get handed an OF-11 form. It has the total number of pax and bags and where the bags are and if they're carry-ons. The F/A hands us a pax count and where they are in the cabin. We then take average weights, add them up and get the Ramp, Takeoff and Landing Weights. The captain normally spins the See Gee wheel, gets the Index, Trim, Forward and Aft Limits.

I then take the weights and go into the T/O Speed and Climb Charts. I get the T/O Speeds and climb power settings. If we're light enough, we can do a reduced power T/O. We have to make sure we're on the right chart.

Keep in mind, this is all happening within 3 to 4 minutes before departure, so I'm constantly a busy man. It can be nerve racking, but once you have the hang of it, it goes quickly.

That's it. All there is to it.
 
I've tinkered with the paper work also and have found out that on the 300 series you can put around 1500 more pounds in the back and it will just barely stay in trim. The 500 is somewhere around 55 bags up front before you have to throw something in the back before it goes out of trim. But the 300 is a pain to split the 50/50 load. As with the 700 load it how you want it'll go..........I Love the 7's!
 
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I'm trying to figure out how SWA and ATA haul big loads on long legs out of MDW

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Freight, my man, freight. I had a MDW flight last night that only had 30 bags, but it had 3000 lbs of freight. Mostly aquatic fish and large Hawaiian Tropic displays.
 
We add up the weights and then spin them on a CG computer (a circular computer much like an E6B) to get the index. If the index is within limits, we're good to go. The whole process takes less than two minutes.
 
[ QUOTE ]
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I'm trying to figure out how SWA and ATA haul big loads on long legs out of MDW

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Freight, my man, freight. I had a MDW flight last night that only had 30 bags, but it had 3000 lbs of freight. Mostly aquatic fish and large Hawaiian Tropic displays.

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No, I mean how you get anything on the airplanes with enough fuel to go anyhwere.

I can see SWA not having too much trouble with the short 73s. But ATA with the 800s and stretch 75s bogges my mind. They go down to Guadalajara every day about the same time I do, guess I need to walk across the ramp and ask them.

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