AAR90, unfortunately the flight dispatcher role in the USA is not available to us in Australia, all our performance calculations are performed by the pilots.
Oops, sorry to confuse y'all. The dispatcher has nothing to do with the ACARS & TPS functions I mentioned. If the info you're requesting is already calculated DECS (Dispatch Environmental Control System) provides the data automatically. If not, an alert is sounded at the appropriate Load Controller desk and that controller (or any Load Controller seeing the alert) can send the data in about 5 keystrokes. Virtually everything is automated.
"...not ready to go yet, waiting for our numbers".
This usually means the flight crew is awaiting the final load "closeout" information (weight/balance, pax count, etc.). This info is required
prior to takeoff to verify the TPS (Takeoff Performance System) data is accurate and usable. If new information is required, then the phrase means the crew is awaiting the additional info --pretty rare for N.A. operations.
About the AA Departure Plan, is that how the flight plan is called, or do you have a separate plan for departure data at AA?
The Departure Plan is but one small part of the entire AA Flight Plan/Release. For a "domestic" operation the Departure Plan uses less than 10% of the paper the rest of the Flight Plan/Release requires.
How does one know, or find out about a certain runway that is simply not usable for takeoff given the present variables? Does the departure plan state that?
"NOT USABLE -- WEIGHT" (or whatever parameter prevents its use). We'll also see zeros (000 000 000) or dashes (--- --- ---) where data would normally be so we can't screw up and use invalid data.
Here in Mexico City, flights to Europe request 05R over 05L 95% of the time. Many flights to South America and some flights to USA/Canada (i.e. A320 flts MEX-YYZ, MD80 flts MEX-DFW, etc.) make this request as well.
DECS is not accessable from home so I don't know the specifics of MEX runways, but a quick look at Jeppesen charts shows 05R takeoff distance available is 12,795 feet while 05L takeoff distance available is 11,325 feet (page 10-9A).
I'll leave the AA stuff to AAR90!
AA dispatchers & load controllers have the ability to manually place limitations on the flight and the computer programs will automatically consider those when doing all of their calculations. All-in-all a pretty nifty and very
reliable system. Which explains why AA has found no need to upgrade it even though it is mostly vintage 1970's technology.