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Flap Extension Times

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Hi,Can't wait for the 744F and I have a quick question regarding flap extension times. I've noticed that going to flap 5 takes a long time (ages) however this time does not match that of PS1. In fact there's a reasonable/noticeable difference. My question is why? Perhaps a PS1 user knows the answer?Thanks,Paul

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hmm. good question. perhaps you could also post this query on the PS1 forum.all i know is that from what has been advertised, and touted, it is the position of pmdg that the flaps operations mimics the real world 744.maybe pS1 has it wrong. tj

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Another difference I can think of is the time it takes the engines to spin up to take-off thrust. Perhaps this is a limit of FS9 more than anything?

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In PS1 some things are "simplified" and this does not mean that it's any big deal. Another example of this would be the delay one sees when using the FMC and EXECU. On the real 744 if one selects the arr/depp page there can be a long pause since the real FMC is based upon old technology or any modifications. So to answer your question, yes the PMDG is correct in flaps timings although that is not to say it is down to the very second timing just that it does take "time" to deploy................Randy J. Smith................A PROUD MEMBER OF THE PMDG BETA TEAM[h4]Evolution is a process that results in heritable changes in a population spread over many generations[/h4]

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In this case, in my opinion, the PMDG 747 is inaccurate.I fly British Airways across the atlantic at least 6 times a year in business class and most times (because i request it) i get a window seat facing backwards and looking directly at the leading edge of a wing. Those leading edge flaps (are they called slats?) do not deploy or retard as slowly as modelled on the PMDG 747. They go a lot faster than that in the real thing. I have always been puzzled why the PMDG version goes so slowly. I never bothered to comment on it before though.Anthony

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Are you talking about flaps1? or 5? the slats start moving w/ 1.Do you know the lag from the lever is commanded to 1 or 5 to when the extension stops? I'm not convinced by your argument that PMDG's work is inaccurate.Perhaps I misunderstand.PatAMD A64 4000+ @ 2.6GHz, Zalman7700Cu cooler, Corsair XMS 1GB DDR, LTK6800GT-OC, Asus A8V MoBo, WDRaptor10KrpmHDD, TrackIR4, CH FSYoke + TQ, XP-hsp2

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Well you are welcome to believe what you think is correct but we have a mechanic and more than a couple pilots of the real 747-400 who claim otherwise... ...............Randy J. Smith................A PROUD MEMBER OF THE PMDG BETA TEAM[h4]Evolution is a process that results in heritable changes in a population spread over many generations[/h4]

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I have seen the extension/ retraction time vary quite a bit on the pmdg 744 depending on the speed you are going sometimes very fast and sometimes very very slow when this happens they usaully start quick and then the last stage takes forever. i dont know if this variation occurs on the real thing depending on certain influencing factors like resistance loading for example and if such thing were taken into account in the pmdg 744 modelling. So all i can assume is that the real 744 pilots and mechanics mentioned have never experienced the pmdg 744 doing this.So those who claim that the pmdg 747 flap time are not always accurate are not making things up, i cant explain why the speed changes but i can deffinately say it does. I stood near to a real 747 400 today as it taxied to the gate and watched its flaps bieng retracted and it was a speedy process as was the extention to flaps 20 of a departing aircraft and the speed of both seemed pretty much the same as the PMDG 744 has been on occasion but other times the pmdg was drastically slower it almost seems to hang on flaps 25 ,to 30 taking 40 secconds or soKav

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flaps 25 to 30 is very fast you were probably too fast so the flap relief system had to kick in.

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>Another difference I can think of is the time it takes the>engines to spin up to take-off thrust. Perhaps this is a limit>of FS9 more than anything?All Jets (Turbo jets, turbo fans, turbo props) need a certain amount of spooling time. Thats why when you approach to land..you need a certain amount of thrust (N1 not less than 60% or something.. I forget) (sufficiant spooling in case of go arounds) but counter it with a lot of drag. for jets, Its easier and quicker to remove drag (flaps etc...) than to spool up on time.I have never flown a Turbine aircraft for real..but thats my understanding.Real Turbine gurus can add their 2cs.Manny

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I mean the slats which deploys at 1 and 5. I beleive the PMDG747 version is much slower than in the real world 747 (especially on retraction - it seems to take forever). It may be, as Randy says, that real world pilots can vouch for the PMDG version but i know what i see as i seat facing those slats in the real world. They are not as slow as my PMDG747.Now, that does not mean that i do not enjoy my PMDG experience so no one has to be defensive or snippy. I am just saying that the PMDG i fly on my pc is inaccurate in this regard compared to what i see when i fly in the real world. Its no big dealAnthony

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Anthony, unless you can measure both travel times with a stopwatch (or equivalent) and compare them side-by-side I would have hard time putting any value in your observation. When you sit by the window in a real aircraft or sit at your PC flying simulated aircraft - these are drastically different experiences and your mind has different expectations as to events and their timeliness. So if you really want to contribute in this area - after your next trip please report on the exact number of seconds and the issue will be settled.Michael J.http://www.precisionmanuals.com/images/forum/pmdg_744F.jpghttp://sales.hifisim.com/pub-download/asv6-banner-beta.jpg

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Remember that the first bit of extension is not just the Leading Edge slats, but the Trailing Edge flaps are also coming out too. It's the TE flaps that take the time. The TE flaps are driven by long torque tubes connected to large hydraulic motors in the wheel wells (What hydro system(s) power the flaps?) These torque tubes run the length of the wing and then drive angle gear boxes at each flap track. Finally there's a jack screw that actually pushes/pulls the flap up/down that massive track. The jack screws are the diameter of your upper arm. Get in close to the flap tracks in the model. PMDG's model (skin) put some time in on this. It will give you a feel for the dimensions. There's a lot of motion going on and those TE flaps are HUGE. They take a while. Really want to wait . . . try putting EITHER the LE or TE flaps down electrically. Dang. Go get some coffee. Come back later!But normal LE slats extension is very quick. Bamm, they're out. 3-4 seconds max. They also make a heck of a noise because they're driven by pneumatic motors. It's always fun to watch the ramper-noobis scatter the first time they hear those things come out IRL . . . and they come out FAST . . . almost as the noobies diving for cover! Make sure you have the inboard engine cowls closed before you put

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Values quoted in my manuals for LE and TE are very vague (perhaps to cover hydraulic/pneumatic and aerodynamic load variations).For ground ops (no air loads):LE's take about 9 seconds (this value is more to warn people not to stick their heads between the wing and the flaps without completely deactivating the LE flap system... They maybe won't have time to get out the way of the flaps).TE's take 40 to 55 seconds (the inboard and outboard extension times could vary, but it must not be more than 10 seconds).I have no split times... say for 1 to 5 units. Can't say I've measured the times in the sim, but if the flaps are taking 40 seconds to travel from 25 to 30 units, I agree with the other gentleman... you're flying too fast for the current flap setting.Cheers.Q>

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Sorry, P, but I don't spend a great deal of time thinking/worrying about such things. I just know that the 1~5 movement is a lot slower than all the others.... because the flaps have further to travel. In a lot of cases during maintenance, we deploy the flaps electrically... It's like watching the grass grow :)I've never done flap checks per se... I usually deploy flaps simply to get access to components on the rear wing spar.Cheers.Q>

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Thats a good idea Michael. As a matter of fact, i'll be making one of those transatlantic trips in the second week of March. I will get a timer, insist on a window seat facing backwards, and time the whole thing. Just for giggles. I will report my result on this forum.In the event that i am unable to get the right window seat, oh well.In the meantime, lets all anjoy the wonderful Queen as is.Anthony

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"Remember that the first bit of extension is not just the Leading Edge slats, but the Trailing Edge flaps are also coming out too."Not from UP to 1 ;)"But normal LE slats extension is very quick. Bamm, they're out. 3-4 seconds max."Subjective measurement... or objective? Why do the manuals say 9 seconds? I think someone already commented on the objectivity of this. When you're ducking for cover when you hear the drive motors running, things may seem to be happening faster than they are :)CheersQ>

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>Hi Q>>>Can I direct you to this post;>>http://744.hoppie.nl/forum.cgi/read/9129>>Do you find these settings more/less accurate?>>Thanks,>P>>>"accurate?" Accurate in comparison to what? The default 744? Not one of those replys deal with the real 744 timings, if these guys base timings on what PS1 models then the real question that should be asked is why their model does not match the real aircraft and published manuals on this subject. The truth is that the majority of these PS1 users do not own the PMDG plane and take PS1 as the final authority on everything 744 and that is an issue................Randy J. Smith................A PROUD MEMBER OF THE PMDG BETA TEAM[h4]Evolution is a process that results in heritable changes in a population spread over many generations[/h4]

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Anthony,I fly on a trans-Atlantic on weekly basis with the "other" British 747-400 operator,but normally facing forward.(left seat of the flightdeck)I can confirm our flap extension times are on a par with those of the PMDG model.We also offer a superb flat bed and massage service for the same price you are paying for your seat with the other mob! You should consider giving us a go,and it will make your simming seem more realistic with regards flaps!best wishesJon

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Hi Jon,They should promote you to Public Relations Manager ;) Nice to see how with diplomatic words you are promoting the flying lady ;)Many regards Michel

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Funny Jon. I do get flatbeds on my flights too (but no massage service..mmmm..looks like i'm missing something). Anyway point taken. Maybe i'll give the "other" British 747 operator a shot one of these trips. After i've timed it on my next trip.Anthony.

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flaps 0 to 1 10 secondsflaps 1 to 5 32 secondsTimed them on my way into San Francisco this afternoon,how does that compare? I did check the PMDG model during early beta testing and remember it being pretty near?Antony, no "point", or sarcasm intended with my last post,honest.Best wishesJon

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>flaps 0 to 1 10 seconds>flaps 1 to 5 32 seconds>>Timed them on my way into San Francisco this afternoon,how>does that compare?Was that on taxi to the departure runway jon?, id imagine on descent its too busy to get out the stopwatch :)

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