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757 Flight dynamics

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I wanted to know if the different models RR/PW or 200/300 or winglet version had their true flight dynamics simulated or was it one general flight file for all the variants. Example: I know that the 757-200 winglet version has a higher cruise altitude at lower fuel consumption than the standard 200. It would be cool if it did. I love this aircraft and thanks PSS for a great package with the different models and liveries included...nice treat!Ruben RomeroFS9 "THE LAST TRUE SIMULATOR"

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I looked over all the air files closely and I could find absolutely no bit of difference between them other than the fact they had different names. So the only difference between your RR and PW 757s are different gauges on your cockpit and a different model. I guess Rob Young didn't have time to do anything else. ;-)They may be tagging the winglets with the entry in the [AIRCRAFT GEOMETRY] section in the .cfg. Also, the static thrust is slightly different in the aircraft.cfg for the engine variations, but I would have hoped he'd have invested more time into the 1500 series tables for each engine variation. edit by MOD: No need to shout.

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To answer your question Rob Young is curerently looking at the FDE to see if it can be tweaked any further.

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In the spirit of cooperation I'd love to offer my services, free of any sort of obligation from PSS or Rob, to the FDE tweaking. Please give Rob Young my email address:jochenheiden@san.rr.comAfter thoroughly reviewing the FDE I have a number of suggestions and/or fixes to offer him and maybe we can work together to produce another patch for the community.

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Good Newsthe PSS 757's dynamics are poorly modeled. Refer to my posts about VNAV climb.I also recently noticed a strong "crab" behaviour when strong crosswinds are encountered. I did not notice this on other addons.A question to finish:Is the "Intercept" function modeled in the FMC. I did not find it by maybe it is somewhere?RegardsGhiom Viguie

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Hi Ghiom, the ability to intercept an airway or your route is there. In the pegasus fmc used on the 757 there was no key function for this. If you are flying the aircraft on hdg select mode on a heading towards your planned route and your arm LNAV it will be shown in white in the FMA below HDG SEL and as you intercept the planned route (magenta line) LNAV will become active. I hope that helps Steve

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"I also recently noticed a strong "crab" behaviour when strong crosswinds are encountered. I did not notice this on other addons."Crabbing is a real issue faced by pilots, and covered intensively in the aircraft manual written by Boeing, and individual operators.De-crabbing and side slipping during the flare can be a real spectacle to watch if get to go spotting on a windy day.

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Thank you for the "intercept" advice.Regarding the crabbing, the one I am referring to is during high altitude cruise. Not at all to the same extent for the 777LR. Sometimes 10-15 degrees off-set.RegardsGhiom Viguie

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I haven't tried this, but I noticed in other addons that tried to represent a reasonable engine out asymmetric dynamic that the side effect is impacted yaw behaviour. Perhaps this is the case here? Although 10-15 degrees heading delta with a full cross wind component seems fairly reasonable with upper winds.

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I think you're confusing crabbing with a wind correction heading.Like Mr. Chips said, depending on the wind intensity and its direction you may have to fly a significantly different heading to maintain the desired track. That has NOTHING to do with the FDE.

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Maybe there will be some kind of airfile update for the different variants. The flight dynamics realy seem kind of generic as if I have the realism setiings down or somthing. I also get that crabbing effect at high altitude. I love this plane but it does seem that the 777 had a little more time with the beta team. Just the little things that make me wonder, like the strobes seem odd and no wing or flap vortex effects....mmmmm.Ruben Romero "FS9 THE LAST TRUE SIM"

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Ruben,Grateful if you {and perhaps Ghion} would explain "that crabbing effect" in more detail then I can try and reproduce it.I assume that you are aware of the relationship between heading and track so that this must be something different.RegardsJohn Rooum

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The crabbing effect that I am speaking of is when the plane is flying on a heading and you're trying to take a cool screen shot and then it gets hit by the biggest gust of wind in FS history and the plane yaws 10-20 to the left or right and then banks like a fighter jet to correct itself......:(Does this about 4-5 times a flight.Ruben Romero

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Samr for me.heading some 15-20 degree left or right of the track.Theoretcailly OK, but I believe excessive, compared to the 777LR and other addons. Anot not only in case of strong aloft winds.Personnaly, I can libe with this. The biggest problem to me is related to the VNAV climbs and descents, and the de-rated climb effects, which are not taken into account, I believe.Regards,GhiomNote:The 757 is very good for all approah/landing phases, especially, GS and LOC tacking, speed reduction.

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Sounds like you need to get your high altitude winds aloft under control. This has nothing to do with the flight dynamics of any simulated aircraft. FS will kill you with wind gusts and rapid wind direction changes. Registered version of FSUPIC will fix this with wind smoothing for FS9. No wind smoothing is yet available for FSX.Jim Harnes

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Or buy Active Sky 6. This is not FDE related. The response of the aircraft with course corrections is one thing, but since these rapid high altitude windsheers are not realistic, don't expect the plane's response to them to be either.

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Good point......Well back to the topic I still think the flight dynamics should be correct for the different variants:)I mean how real the planes systems are and then there's always something left out, never do we get a complete palne.....and how well does active sky work does it make flying in weather feel realistic.Ruben Romero

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Hi Ruben, I am delighted that Rob and Steven are working on the FDE's to improve the flight dynamics of the 757, which at the moment is a good model but being greedy I want great :( However I can't see how at the moment PSS can produce accurate FDE's for winglet models when the figures Boeing provide are themselves sketchy, approx 5% fuel saving, possibly 200m extra range, improved performance at high altitude airfields and possible increase on payloads. Most of those improvements could be see by just changing the way we fly the aircraft using real world cost index's and airline procedures to maximise engine life and fuel savings.In time there might be sufficient data to model improvements, but at the moment I think Rob needs a lot more info on power setting's and climb rates to be able to give us something worthwhile, One look at the A380 models available for FS and we can see what happens when you don't have all the information. Oh and once you use active sky you won't fly any other waySmooth landings Steve

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Ruben,Steve has it very right. Manufacturers try to ensure minimum changes between models to reduce crew and other operating costs and I suspect that the law of diminishing returns applies here - is the data available to differentiate the FDE between the 12 different 757 models and, if so, is it worth the all effort to possibly get a very small change which very few customers will appreciate or even notice?Regards to allJohn Rooum

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