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alex394053

Performance-limited TOW planning

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Hi

 

I have a question regarding performance-limited TOW considerations when preparing your long-haul flights. What is your typical workflow?

For example in my case I plan a KLAX-VHHH flight with B777-3000ER. I assume here that there is a strong demand for this flight, so all pax seats and cargo capacity can be easily sold out.

 

My steps:

 

1. In PFPX I choose MAX as a payload.

2. Compute flight and get TOW.

3. Get ATIS and make assumption which runway I'll be taking off from.

3. Open Toper, enter TOW, ambient conditions, runway, etc.

4. Choose flaps 5. Calculate. TOPER usually reports that TOW is too large (regardless of runway).

5. Then I try flaps 15&20. If one of these flaps is OK then I go with them into the flight.

6. If TOPER still reports bad TOW I start decreasing it until TOPER approves.

7. In case I decreased TOW I then go back to PFPX and start decreasing my payload until TOW equals the one from previous step and recompute FP.

DONE.

 

 

Is it valid way or is there more valid/smart way to do this? How is it done in real world?

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I think I'm starting to get into it. Found this document

 

http://www.aircraft-commerce.com/sample_articles/sample_articles/flight_operations_sample.pdf

 

There is a table on the last page that contains precalculated figures for a given route showing how much pax and cargo I can take. Am I right that airlines use such tables to plan their ticket/cargo capacity sales? Are there other sources for this info where I could get this numbers for my particular route?

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No answer, so I ask more general question: could you guys recommend some comprehensive flight planning guide 'from ticket sales to brake set at destination'? How do you approach planning? In other words what is your typical workflow?

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That's a big ask - I will try and give a brief explanation later, but I have to go to work now.

 

By the way, I found TOPER too restrictive, it doesn't seem to be very accurate to be honest - I made a spreadsheet from the FPPM/FCOM that calculates takeoff, but only with Flaps 15.  It is less restrictive.  It still doesn't use improved climb, as its a balanced field calculator, but I can send you a copy if you like?

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in the real world you can sell all the tickets you want but you need your passengers to embark ...

 

if you choose bangkok and the a343 some operators find out that the wet season was a very limiting factor you needed to left some passengers and luggages ...

 

so first you need to know for the day what i can take for load (pax, mail,load and or freight) with the limitations of the flight profile will be at the take off, erops mountaineus area or anything else like the availibilty of your alternates ... and if can do it safely ...

 

so when a company decides to open a new route they need to study the feasibility and money making ( you re supposed to loose money) and for different time of the year ...     

 

back to the OP the TOPCAT profile will tell you what you can do with your plane for the day. i did start using a 777f profile with 777300er weight limitations. pretty sure i shouldnt be far from manual .... today your limitations is  341608 kgs for flaps 5 ...

 

************************************************************************************
* KLAX 25R         * FLAPS 5    * TO         *           LOS ANGELES INTERNATIONAL *
************************************************************************************
:  ELEVATION =    94 (FT)   :  B777F/GE90-110B1L            :                      :
:  SLOPE     = +0.20 (% )   :  DATED 31 MAY 2018 23:22 UTC  :  ALL WEIGHTS IN      :
:  T.O.R.A.  =  3685 (M )   :                               :  KILOGRAMS (KG)      :
:  T.O.D.A.  =  3685 (M )   :  AIR COND ON                  :                      :
:  A.S.D.A.  =  3685 (M )   :  ANTI ICE OFF/AUTO            :  NOT FOR             :
:  LENGTH    =  3685 (M )   :  RUNWAY COND DRY              :  OPERATIONAL USE     :
:  WIDTH     =    46 (M )   :  QNH  1013.25 HPA             :                      :
:---------------------------:-------------------------------:----------------------:
: ENGINE OUT DEPARTURE (EOSID):                                                    :
: NONE                                                                             :
:-------:--------------:--------------:--------------:--------------:--------------:
: TEMP  :  WIND COMP   :  WIND COMP   :  WIND COMP   :  WIND COMP   :  WIND COMP   :
:  °C   :   -15 KTS    :   +0  KTS    :   +10 KTS    :   +20 KTS    :   +30 KTS    :
:-------:--------------:--------------:--------------:--------------:--------------:
:  -10  : 300521 OBS(A): 339674 OBS(A): 342530 OBS(A): 345386 OBS(A): 348241 OBS(A):
:       :  158 167 174 :  170 179 182 :  172 180 183 :  173 181 183 :  175 181 184 :
:-------:--------------:--------------:--------------:--------------:--------------:
:  +0   : 300521 OBS(A): 339674 OBS(A): 342530 OBS(A): 345386 OBS(A): 348241 OBS(A):
:       :  158 167 174 :  170 179 182 :  172 180 183 :  173 181 183 :  175 181 184 :
:-------:--------------:--------------:--------------:--------------:--------------:
:  +10  : 299485 OBS(A): 338593 OBS(A): 341455 OBS(A): 344316 OBS(A): 347178 OBS(A):
:       :  157 166 173 :  170 179 182 :  172 180 183 :  173 180 183 :  175 181 184 :
:-------:--------------:--------------:--------------:--------------:--------------:
:  +20  : 298450 OBS(A): 337513 OBS(A): 340380 OBS(A): 343247 OBS(A): 346114 OBS(A):
:       :  157 166 173 :  170 179 182 :  171 180 183 :  173 180 183 :  175 181 183 :
:-------:--------------:--------------:--------------:--------------:--------------:
:  +30  : 297414 OBS(A): 336432 OBS(A): 339305 OBS(A): 342178 OBS(A): 345050 OBS(A):
:       :  157 166 173 :  170 178 182 :  171 179 182 :  173 180 183 :  174 181 183 :
:-------:--------------:--------------:--------------:--------------:--------------:

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On 6/1/2018 at 12:22 AM, VHOJT said:

That's a big ask - I will try and give a brief explanation later, but I have to go to work now.

 

By the way, I found TOPER too restrictive, it doesn't seem to be very accurate to be honest - I made a spreadsheet from the FPPM/FCOM that calculates takeoff, but only with Flaps 15.  It is less restrictive.  It still doesn't use improved climb, as its a balanced field calculator, but I can send you a copy if you like?

I do like. Thanks a lot. Please, look in PM for my e-mail address.

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