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zachenbacher

Takeoff performance calc/FLEX performance

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Dear friends,

 

I've set up the Tinmouse 1.40 for FSX the last days and now have a well equipment and lovely old lady. Everthing works and it's a pleasure flying the old style (steam gauges, old nav and comm dials, CIVA INS and so on). I also found out the Tinmouse reacts quite realistically the the FSX triggered failures (more realism).

For a serious simmer it's important to have good information for flightplanning. I think that's given by the 737 reference htmls and the FSBuild performance data included in the package. But there's one thing missing: Takeoff performance charts! Ok,it's good to know V1, Vr and V2 in relation to TOW. But I need to know how much is the needed take off distance under changing environmental circumstances (V1 also is dependent on these values). And it would really cool to be able to calculate FLEX temperatures for reduced thrust takeoffs.

 

Within the package are 3 original Aircraft documents nearly 1000 pages. But as far as I can see there are no performance charts included.

 

So does anbody could give me a source where I could get or buy 737-200 performance data. Especially for real life takeoff calculations?

 

Thanks in advance!

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http://www.boeing.com/commercial/airports/acaps/737sec3.pdf

 

Page 108ff.

 

 

I strongly doubt that 732 pilots had to do these stupid FLEX calculations back in the 70s and 80s. If you wanted to save fuel, you just reduced cruise speeds.

The 732 doesn't have a FMC and autothrust to support any meaningful application of reduced t/o thrust in the first place.


7950X3D + 6900 XT + 64 GB + Linux | 4800H + RTX2060 + 32 GB + Linux
My add-ons from my FS9/FSX days

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Thanks for your reply.

 

Ok - forget the FLEX calculations. But you need some more data (than on this graph on page 108) to calculate a takeoff.

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V-speed calculation is done by the ASI and EPR recommendations are set by the performance computer. All described in the manual.


7950X3D + 6900 XT + 64 GB + Linux | 4800H + RTX2060 + 32 GB + Linux
My add-ons from my FS9/FSX days

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Who cares?

 

 

Seriously, just get an *idea* and NOT a number with seven decimals about t/o performance. There's no way you will ever be able to catch the V-speed and EPR bugs by more than 90% anyway, so why bother with all the performance table stuff?

 

Number crunching ("Oh dear, we're 0.000021 lbs above allowed fuel flow, dispatch is going to kill us!") is for the 21st century and just doesn't fit into the TM's portfolio.

Due to lack of computers, the 732 is a pure pilots airplane. Just use what you have plus seat-of-the-pants reckoning and you will be more than fine in this bird.


7950X3D + 6900 XT + 64 GB + Linux | 4800H + RTX2060 + 32 GB + Linux
My add-ons from my FS9/FSX days

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In the real world, take-off and landing performance calculations are normally done by a dispatcher in the airline's flight dispatch office.  However, very occasionally it may be necessary for the pilots to make such a calculation, for instance if you found yourself landing somewhere that you didn't expect and you wanted to be sure you had enough runway length available under the prevailing weather and load conditions.  In that case you would have to go to the 737 aircraft Flight Manual where you will find the relevant charts but be aware that it involves very complex and detailed use of the charts and it's very easy to make mistakes.  For instance if you want to know how much of a load you can lift from a particular runway under existing ambient conditions you would have to determine from the charts the highest gross weight possible but you could be limited by structural, WAT or runway.  The structural limit, maximum take-off weight, is 119,500 pounds and doesn't change but you will likely be limited by WAT or runway length so you have to calculate the WAT limit and then the runway limit from the relevant charts and the lowest of the 3 is your maximum take-off weight for that runway under those conditions (of temperature, elevation, wind and runway length).  The aircraft Flight Manual is normally carried in the aircraft and not by pilots personally.

Flex take-off in the 737 is actually done by the PDCS but I don't think the flex page is modelled in the Tinmouse PDCS.  If you don't have the PDCS it's done by the "assumed temperature" method and can be done very easily just by looking at a chart, it's quite simple but you have to have the chart of course.
 

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Investdude,

 

thanks for your answer!

 

What you mentioned is very clear to me - but I need that CHARTS!!! I spent a lot of time to get them out of the net but there seems to be no source available.

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