The importance of introducing

The importance of introducing

Sorry Rob but you haven

Sorry Rob but you haven

There are some excel tables here in the Avsim file library. Search for "Bryan Schleipen". Or don't use flex if you think it is too much bother - after all, it's only virtual engine wear :)

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Appologies, just going to hijack your topic for a mo. Are you using Utopia 1.2? I see it's for FS9 - I assume it's still fine for using with FSX?Thanks

I'm glad this thread was started as I've wondered the same. I normally just leave it blank since like Tom said, it is just virtual wear and tear. But now that I am more comfortable with more of the systems I am starting to venture out and get more involved with more aspects of what's available. The FMS manual on pg#44 says the max is 70c. I downloaded Utopia and also the MD-11 files but can't seem to find anything about Flex. I see the "Derate", but no matter what data I enter this stays the same @ "Derate: Eng 61.5k : Max*".So how or where does it show the Flex value exactly?Here's a screenshot if that helps.I'm looking forward to learning more about it as well as other systems, but right now can't help but wonder (from what I've learned so far) why they just didn't design the FMS with a simple "Derate = YES/NO" entry, or maybe just steps to how much you want (yes derate @ = Full, Med, Small).Thanks,

Me too - after inputting my data - and letting Utopia put in the rest - where exactly IS the Flex value?Amd another thing: Activesky tells me the temp is 1

Me too - after inputting my data - and letting Utopia put in the rest - where exactly IS the Flex value?Amd another thing: Activesky tells me the temp is 1

Ah, I can help you here - I made the same mistake. Check your take off weight - 432lbs. Try 432,000 and it'll work fine!

Turbine777 from what I can see your departing from a long runway with a low outside ambient temp and your Take off weight is very low (lower then your max landing weight)So Utopia is telling you your available FLEX is 'MAX' as explained in my first post Max flex is 60c Flex thrust is a very complicated thing to figure out and getting it wrong in the real world has caused fatal crashes. That's why most companies these days provide there crews with onboard laptops with software similar to TOPCAT. Both crew members do individual checks and then crosscheck each other.Flammin Squirrel is correct but you will still get max flex at 432,000And to confuse the situation even further, if you want to keep things realistic as far as SOP most companies operating the MD11 would not allow FLEX if the pressure is below 1000mb so I would have gone with Max thrust for your takeoff. Utopia is a basic tool, TOPCAT is much better as it takes into account climb gradient etc RegardsRob

Ah, I can help you here - I made the same mistake. Check your take off weight - 432lbs. Try 432,000 and it'll work fine!

Haha, Doh. Guess I'm use to adding numbers the flight level way ;-)Thanks,

Turbine777 from what I can see your departing from a long runway with a low outside ambient temp and your Take off weight is very low (lower then your max landing weight)So Utopia is telling you your available FLEX is 'MAX' as explained in my first post Max flex is 60c Flex thrust is a very complicated thing to figure out and getting it wrong in the real world has caused fatal crashes. That's why most companies these days provide there crews with onboard laptops with software similar to TOPCAT. Both crew members do individual checks and then crosscheck each other.Flammin Squirrel is correct but you will still get max flex at 432,000And to confuse the situation even further, if you want to keep things realistic as far as SOP most companies operating the MD11 would not allow FLEX if the pressure is below 1000mb so I would have gone with Max thrust for your takeoff. Utopia is a basic tool, TOPCAT is much better as it takes into account climb gradient etc RegardsRob

Thanks Rob, I fixed the stupid weight mistake of 432,000. Guess some of us are use to those 3 digit numbers. I just wanted to make sure I was looking in the right spot.I tried a warmer temp of 20c and corrected my weight of "432,000" (2/3 full pass and cargo w/ 55k fuel), and now it reads "Derate : Eng 61.5k : 56C" so if I'm understanding this correctly, my derated thrust value is 56c to be entered in "FLEX"? I'll look into Topcat, but right now just trying to better understand the basics of flex as well as the app.Also, what do you mean the max is 60? The FMS manual states 70c and it does allow up to 70 to be entered. Or do you mean the apps only max out at 60? Oh and as far as it being complicated and getting it right, tell me about it. After I was out of the basic tutorial and started setting up my own flights, I often didn't make it off the ground but rather coasted down the RW.Thanks again for the assist!BTW, call me Dan as in my sig, only my girlfriend calls me Turbine. :(

FLEX and derate are not the same thing...Derate reduces the maximum thrust available from an engine. It derates the engine to a lower maximum output in other words..."FLEX or "Assumed temperature" is the maximum ambient temperature that will provide certificated takeoff performance for the given airport/runway and aircraft gross weight". Thanks to a poster on PPRUNE's forum for this...You may not use assumed temperatures for runways contaminated with standing water, slush, ice, or snow. Normally, FLEX is not used with tailwinds on takeoff either...The assumed temperature reduces the takeoff thrust setting without affecting the max thrust available from the engine on selection of TOGA. The reason for doing it is reduced wear, engine longevity, reduced operating costs, and so on...I use the excel file mentioned here, Bryan Schleipen's..., which has so far worked really well every time... It is a function of TOGW, runway length, runway altitude, QNH, as well as headwind/tailwind component. It reduces the calculated takeoff thrust such that takeoff is still possible and safe within the runway length available. You set too high an assumed temperature and you might not reach Vr before the end of the runway :(Combined with the MD11, I have always seen V1 to be such that an abort would still have me stopped within the remaining pavement available, as long as I have the correct runway lengths and other parameters...PM me with your e-mail address if you wish me to send the file to any of you... The zipped file is <250Kb...The MAX FLEX possible on the MD11 appears to be 70