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JSACKS

777 THR REDUCTION activation after t/off

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Does the FMC governed thrust reduction demand that one fly with an active flightplan in order for this function to operate after takeoff? I ask because I've done several takeoffs using FMC PERF INIT data filled-in, flying with the MCP, but without an FMC flightplan and it seems that the thrust reduction does not kick in as I would have expected once passing the FMC indicated thrust reduction altitude. It does appear to kick in if I select a different vertical profile such as FLCH. It's not a big item but I am curious about this. Thanks!JS

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Hi!The simple answer is yes, it does need a flightplan. The long answer would fill pages. :( Soft Landings! :(

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But there is a bug in the 777 FMC that when you take off with a CLB thrust reduction preset, you will never be able to go back to full CLB in higher altitude resulting in very low climb speed above FL240.In fact, the FMC does it but the engines don't react to it...Not sure I was clear.RegardsGhiom

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Hi Ghiom!That is new to me! Never saw not been able to get full CLB power! I normally Take-off with derated power, assuming 40-47C and CLB1 or CLB2 according to prevalent weather conditions and rwy. On the FMC main menu, there is a page with the engine regime, you can use that to make sure you are in full CLB power.BTW, just to check, is your version fully updated to SP2? If you have the JF version, you can still download them from their website. If it is the PSS version, sorry!Soft Landings! :(

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Hi again!As I write this my B777-200LR is reaching cruise altitude of FL320, climbing at 1500fpm past 25000ft, 310KIAS and the engine is at CLB setting of 96.9%. That is for a EGKK-KATL flight of 3200NM, ZFW of just over 170000Kg and 61tonnes of fuel.There is not a single problem. If you meant by full CLB power, the ability to reach 100% N1, than that is not possible due to the computers governning it limiting engine power.Soft Landings! :(

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ThanksCould you please send me your fde air aircraft cfg files at ghiomkl at hotmail dot com?I would like to enjoy the same performances as yours!ThanksGhiom

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I fact, the fact is that you can select full CLB power on the FMC but the N1 rating will not change!

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Ghiom,At what altitude that occurs? There is a derate "wash-out" at 12000FT. That means that regardless of CLB, CLB1 or CLB2 selected, the engine will give the same power, roughtly 94% at that stated altitude. That is the correct behaviour. The B757 came with the option of setting this feature or not.I point to you that the fde was tested by real world 777 pilots and it was satisfactory to them. Due to limitations of FS, there's allways a margin of error.If you don't have the full SP2 version, I remind you that PSS are not trading at this instance and only the kindness of some users would be able to help you. If you purchased your 777 from Just Flight the 2 Service Packs are available from them and all support questions should be directed to them.I urge you to study this aircraft in more detail and not to judge just because you can't do something there as you would do in a default FS9 aircraft, would be a bug or error.Enjoy it! It is a wonderfull aircraft with one of the best designed panels available!Soft Landings! :(

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ThanksI will check whether I have the de-rate washout option checked!I think I don't.Do you know where I can find a flap extension schedule for this bird?RegardsGhiom

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Hi!No, there isn't an option to turn it off on the 777. Only on the 757.Flap schedule should be available in the manual. Otherwise the PFD will tell you that.Soft Landings! :(

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You mean the washout will occur at 12,000ft is on and there is nothing you can do?Is this real?ThanksGhiom

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Hi!It might not be as the real aircraft. Only a pilot or someone with extensive knowledge of the AOM can tell you. My assumption is that it is a more specific airline option or it might even be pilot option.In any case, at 12000ft the PSS 777 will give you full CLB power according with prevailing conditions.Soft Landings! :(

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HiYesterday I tried the 777LR with clean FDE. It was long since I had not tempted to fly this bird!I flew from KOAK to KLAX (to enjoy Mach-1's new beauty).400,000 pds ZFW + 75,000 pds of FuelI had set a 60

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Ghiom,Hi again.Watching this thread, I'll leave Ricardo to comment in detail. But:Why fly a "clean" FDE - I assume that's the original before PSS released the updates.Also, we have spoken before about this. Do not forget that you are in charge. FLY the aeroplane and ensure that it does what you want it to do - not what you think the computer itself thinks it wants to do. After all the FMC is only an adding machine!I'll try and fly your route next week to see if I can help.John R

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Hi!I don't have much to add to what John has already said. Just a couple of observations:You just observed some of the FS limitations: the wrong tyre friction that makes some aircraft move on with the parking brake set, the contrast between that same friction and the air while on TO.Take-off is normally with Flaps 15: you'll get a lower VR speed.The overshoot of the V2+10 target is normal on this aircraft and it is one of the compromises that were made. The VS of 200-500 at Accelaration altitude seems normal: you want to accelerate while keeping some climbing.The VS of 1200fpm is also normal at those altitudes while still quite heavy. There is a joke between A330 pilots related to that! While the A330 cruises normally at FL410, the 777 does it at FL350!On Approach, with 4NM to go, I normally sellect full flaps While allowing the speed to blled off to the Vref+5.As John said it is your task to fly the aircraft in the first place. Many accidents in real life are due to precissely that.Soft Landigs! :(

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