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Original Aircraft-accuracy?

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A wide variety of original aircraft are created as both payware and freeware. My question is, how accurate are the flight models of these aircraft. That is, if I have one, will it perform as closely as possible, within the constraints of FSX, to a real counterpart aircraft. Many of these have all sorts of "operating" elements but of what use are they if the flight is not as realistic as possible?I have seen some the claims that one or more people who actually pilot these aircraft in some way certify that the flight model is "ok". At the very least we have some foundation for the reality we need to suspend to use FSX. The problem arises when there is no "certification" or, if there is, it is from someone whose credentials are not made clear. Should the the intent be to acquire "good looking" aircraft then the accuracy of flight is of little consequence. However, others may seek a more authentic flight and an from that position arises the crux of the commentary.Regards,Dick BoleyA PC, an LCD, speakers, CH yoke

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"how accurate are the flight models" - Depends on the aircraft.There can not be a "certification". For various reasons, this is much like demanding a "certified" FS addon process whereby all developers must submit their products for "certification" by someone who claims they're an "expert".So.. since you started the subject of "certification"... what's your credentials regarding knowledge of accurate flight models?

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Pull back, things get smaller, push forward, they get bigger, pretty accurate :-)XP Pro SP2-FSX SP2AMD FX60-8800GTS-2 Gigs RAMFEX-GEX-UTUSA-FSGenesis-and a bunch of other stuffComputer optomized by www.fs-gs.com

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IMO-X-plane and some other addon makers think they can feed a computer a bunch of formulas and let it spit out the perfect flight model.On paper everything adds up and then they can proudly post the " flown by the book" headline.Let a couple of guys who have flown the real plane but never touched a joystick, much less a game, and bingo,presto.... Its as real as it gets.I estimate I have around 400-500 hrs in the Cessna highwings. Does that make my opinion or the way I convey my interpretations to a programmer have more weight than a pilot with 200 hrs?I think someone who has never flown would soak in more and be able to describe the feeling better than I would.Things I would not even notice, they would catch.With a simple slider adjustment through your joystick settings, you can ruin a 500 hr pilot and months of work by the programmer.Last night, I kicked in a door,tossed in a flashbang and took on 12 terrorist. Bullets whizzing by my head,glass breaking. I took out every one of them,disarmed a bomb and saved the world.I then reached over and took a sip of coffee.FSX,FS9 are great entertainment and game programmers overall do a wonderful job of temporarily suspending reality.And thats all you are going to be certifying.Now kill this thread before they want to charge more for addons because it was "certified".Wait a minute, they are already doing that.....

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"It takes big man to cry.""It takes a even bigger man to laugh at that man."I love these threads:-abduct

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It's a game. If you want "certification" sign up for flight training or get certified in a Boeing Flight Simulator (I believe FSX tells you how in the Learning Center or visit AOPA). Don't expect to ever become a professional pilot with a $70 game.Best regards,Jim Young

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Getting a sim flight model exactly like the real world is like herding cats. You change one thing, and it changes another thing...But in sim flying I am more interested in having the cockpit layout like the real thing, and have everything work as the real thing. I think that's sometimes easier to achieve than it is to get a flight model "perfect". RhettFS box: E8500 (@ 3.80 ghz), AC Freezer 7 Pro, ASUS P5E3 Premium, BFG 8800GTX 756 (nVidia 169 WHQL), 4gb DDR3 1600 Patriot Cas7 7-7-7-20 (2T), PC Power 750, WD 150gb 10000rpm Raptor, Seagate 500gb, Silverstone TJ09 case, Vista Ultimate 64ASX Client: AMD 3700+ (@ 2.6 ghz), 7800GT

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Full throttle... 80 kts... Crash To Desktop... Not accurate at all______________Efrain RuizLiveDISPATCHhttp://www.livedispatch.orgCooler Master cosmos SDFI LP UT P35 T2R (3-17-2008 BIOS) | E8400 @ 4GHz (500MHz x 8) | 2 x 2GB OCZ Flex II PC9200EVGA Nvidia GTX280Two (2) WD3200AAKS 320GB (Operating System RAID-0) | Two (2) WD3200AAKS 320GB (Flight Simulator RAID-0)Corsair CM PSU-750TX | Asus 20X DVD

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I had a different reply composed but why make Tom's life more stressed. I will say that, for me, the suspension of belief and immersion requires more than dynamic doors or shadowed rivets. While I appreciate these elements, the flight model is my focus since after-all this is a FLIGHT simulator. I have the unfortunate liability of not being a pilot so all I can rely on is a "certification" by some respected person that the synthetic aircraft has reasonable flight emulation. That may be the Holy Grail but the search for it seems to be waning.Back to the verbal party.Regards,Dick BoleyA PC, an LCD, speakers, CH yoke

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I agree and why I only generally fly aircraft in the sim I am familiar with. If the fm's are familiar then I stay with them-if they are not then it is a game.I wonder sometimes-this complex airliner that military jet etc. -how many with experience and are really familiar with these particular aircraft have certified that it is at least somewhat realistic on the sim?If I don't know from personal experience, and no one with greater credentials gives an opinion, we have now gone from sim to game..imho....GeofaMy blog:http://geofageofa.spaces.live.com/

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Which plane?Are you wanting to start taking lessons and get certified?If so, which aircraft will you be training in?I do not know if I qualify as respected but Ive either flown or flown in a #### of alot of planes.I am assuming you are looking for a plane that has received alot of praise by "real pilots" as representing the actual plane or exhibiting aerodynamic properties you would encounter in real life.My humble suggestion is to get the RealAir SF260.

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>My humble suggestion is to get the RealAir SF260.>> Me too........It's suspended my belief for four years or so.Other than that, the default Cessna is "good enough" for flying from point A to B.L.Adamson

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YesFor sombody who wants to get his PP, the default 172 is great.Buy or download the pilots manual for a 172.Load it 100% fuel,pilot,co-pilot 200 pounds each.Get rid of the joystick and get a yoke,pedals.Turn up the sound LOUD.I suggest but not a must have, ActiveSky.It adds a certain amount of realism and life to the air especially turbulence. FSX is not bad.Plane should feel underpowered and like its covered with a wet blanket.Add a good bit of deadzone and lower the sensitivities on the joystick.Follow the checklist.When flying, set yourself goals.Stay dead on the taxi line.Climb to your altitude,say 3000. Get there and HOLD it.Dont be sloppy and make the plane do what YOU tell it to.Maintain alt in turns and keep alt plus minus 100ft.If you do not have a death grip on the yoke and sweat starting to roll down your face,you are not taking it seriously or either your a/c needs to be turned off.Congrats! After 1 hour you just saved a few hundred.

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I also stick with the GA aircraft. I use the RealAir Cessna 172 aircraft.cfg and air file from the FS2004 freeware version. Most agreed that it was one of the most accurate in FS2004. I also use the Flight1 Cessna 172. The big difference between the two is that the RealAir has dihedral and the Flight1 does not. The use of dihedral in the Cessnas is a bit murky as to which model had it. The Flight1 Cessna seems "heavier" than the RealAir. But as a non-pilot I look at the aircraft.cfg and the more non-default (1.0) entries the chances of it being accurate rise in my non-pilot world.I have to look into Active Sky since the turbulence in FSX seems to not consider the "elasticity" of air and the mass of the aircraft. That is, the craft seems to move too abruptly in bumpy air and some of the movements seem to be too repetitive. Passenger flights in a Cessna seemed to be more like a poorly maintained road with small bumps almost all the time and some potholes. The weather was always calm at the time.I think that some may be concerned that Flight Simulator may morph into Airplane simulator. The focus on flight may diminish over time as the market moves more towards the scenery, AI and the appearance of the aircraft. These are quite important for everyone, even those that focus of the flight dynamics. Everything that allows your imagination to think you are in an airplane is a contributor. But is the balance changing?Regards,Dick BoleyA PC, an LCD, speakers, CH yoke

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>But as a non-pilot I look at the>aircraft.cfg and the more non-default (1.0) entries the>chances of it being accurate rise in my non-pilot world.>To be honest, that would be an inaccurate conclusion on your part.

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If you fly the aircraft "by the book" and stay within its real world flight envelope,most are pretty close to their real world counterparts.It appears you want "proof" to validate the cfg values of any given plane.I can undertand your desire.For example, at any given minute on some forum, there is a on going discussion about realism.The landing gear retraction time is slow,the flap time is fast,the strobe blinks fast,the bla bla bla...... We are not even into the flight dynamics.The alphasim F-104 once it hit mach 1, took forever to accelerate to M 1.5. People complained until someone produced actual test pilot reports showing it took up to 5 minutes to go from m1 to m1.5.Still people complained cause it just did not feel right. I mean when you kick in the burners, I want to be thown back in my seat.So Alphasim showed how the user could change the value making both camps happy.In my case, your desire for mathmatical flight model validation is not what flying is about.You line up a dozen 172S and each will handle differently. Some are rigged tight,some loose,some pull left. One might need constant up trim while another the window flies open.Realism to me is not if the stall speed at a certain weight,density altitude falls within small mathematically proven number.Its if the floor mats are crooked,dirty and the dash is cracked from baking in the sun not a 1.0 in the cfg line..Sounds and visuals to me are what makes or breaks a plane or heli to me.

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It all depends on how good the FDE creator is and how they make use of their skills.

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>But as a non-pilot I look at the>aircraft.cfg and the more non-default (1.0) entries the>chances of it being accurate rise in my non-pilot world.In reality, it's just the opposite for the most part. You see, the 1.0 scalars used in the aircraft.cfg file are used to tweak the same paramaters encoded in the .air file.If the scalars are 1.0, then that typically means someone with in-depth understanding of the .air file has taken the time to set it up properly... ;)

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I've been a real-world pilot for over 30 years, and it's like JimJam said above.Go rent 10 different Cessna 172's, and they will ALL handle a little differently. Some will have a "stiff" yoke feel to them, some will feel so loose it's incredible. Trimming will be different in each case. Rudder pedals will be the same way...some "tight" and some "loose".In FSX, it is impossible to simulate that. Any aircraft in FSX will only have one set of cgf and air files that determine "how it feels" when you fly it. Plus the different combinations of controllers available add to the equation. Someone using a CH Yoke will get a different "feel" than someone using a Saitek.Plus (yeah...there's more), if you don't have all the "Realism" settings enabled for the aircraft in FSX (P-Factor, Torque, etc), then any argument is a moot one. Flying without P-Factor and Torque effects (and the others) won't simulate anything close to "real" in the first place.FalconAF

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Ah hah, a very good point. I never knew that there was this close relationship between the two files. Probably, not relevant to using RealAir'172 inside a Microsoft 172 body since I used both the AIR file and the AIRCRAFT.CFG file. However, it does create a higher probability that Microsoft has their 172 closer(1.0 values) to reality than my unsophisticated attempt at adapting an FS2004 airplane to FSX. Probably time to restore the Microsoft 172 and give it a try. As one poster noted there are a great many things that give an airplane its "personality". Maybe my RealAir 172 has a personality a real 172 pilot would not recognize.Regards,Dick BoleyA PC, an LCD, speakers, CH yoke

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I recently took a trial flight in a C152, one of my goals being to see just how well FSX compares to the real thing. I don't have a C152 model for FSX so I can only compare with the C172 -- I suspect the differences between the two planes are less than the difference between FSX and real flying. :)Here's a random selection of the things I noticed:1. Getting into the plane felt a bit like getting into an old car, like a 2CV or something. There was nothing glamorous about it whatsoever. Not that that detracted from the enjoyment though!2. Talking to someone sitting right next to you by means of a tight fitting headset (with a dodgy audio connection in my case) takes a bit of getting used to.3. It really is hard to see over the dashboard, especially while climbing. You've also got less scope for adjusting your viewpoint than you do with a TrackIR.4. It was a great deal easier to keep the plane level at a particular altitude than it is in FSX, even though there was quite a lot of turbulence.5. You can _really_ feel the turbulence!6. I have a habit of looking at the variometer a lot, possibly too much, to make sure I'm not going to drift from my intended altitude. This is probably a holdover from my days as a glider pilot. The vario on this plane however was a couple of notches out so my ingrained habit of trying to keep it centered was going to get me nowhere -- I had to keep it a little high in order to maintain altitude.7. A yoke feels somewhat different to a joystick, but I'm still happy to continue using a joystick with FSX as I don't think it affects the experience in a terribly important way. A pilot with more experience might disagree of course. More important though is the direct feedback you get from a yoke in a real plane (which of course you also do from a joystick e.g. in a glider).8. I had my feet on the rudders, all ready to show the instructor how good my co-ordinated turns were, but I found I didn't need to use them at all to keep the turn and slip centered. It seemed that I didn't need much back pressure to maintain altitude either, but perhaps I was just applying it unconsciously. 9. When initiating an ascent or descent by increasing or decreasing throttle, no yoke input at all was required to maintain a constant speed. I haven't found this in any of the aircraft I've flown in FSX.10. Trimming using a wheel is a lot easier than it is using the 1 and 7 keys.11. It's harder to spot the runway from a distance when it isn't enclosed by a large flat green polygon.12. The instructor's landing was a fair bit rougher than mine are in FSX, even though there wasn't much wind near the ground. This makes me think that perhaps landing in FSX is a bit too easy? Or maybe I'm just not doing it right. I think he brought the plane right to a stall before touching down, whereas in FSX I think I tend fly right onto the runway, so am probably too fast when I touch down. Of course in FSX there are no consequences for not doing it right so your natural instinct is just to try and make it seem as smooth as you can.The OP originally asked how accurate the flight models were. My answer is: as long as they're not wildly out, who actually cares? It seems to me that there's a lot more to the experience than exactly how fast the plane climbs at full throttle, exactly how much you need to move the yoke back to maintain altitude during a turn, and so on, and the skills you need to master are not hugely affected by small differences in these parameters.Since doing this I reckon FSX does a pretty darn good job of simulating flight given the constraints it works under, chiefly a) not being able to exert physical forces on the user, :( the small size of the average display and c) the limitations of the readily available input devices.I would be interested to hear from real pilots on my point about the landings though. Do ACES need to work on this, or do I just need to work on my landings? :)Colin

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Some teach full stall landings and some drive the plane on.Just as the Navy teaches different that the Airforce.Usually, pilots accustomed to miles of runway come in hot,some flap and drive the plane onWhile those from short runways,soft feilds, run alot of flap,power on full stall landings.A full stall,short feild landing keeping the nose up takes alot more skill than just drving it on. But a passenger judges a landing on how "smooth" it is. I didnt even feel it is a common comment.I was taught from a old school Airforce pilot.I do not care if the runway was 5 miles long, you took your plane all the way to the end.Two things no good to a pilot. The runway behind you and the fuel in the fuel truck.Same with landing. Make the first turn off.I suggest to anyone wanting to really learn how to fly stick and rudder, get Aerosofts Lukla and FlyTampas St Maarten.Those 2 sceneries will give even the best Bush pilots a real work out.BTW- I use the Saitek X52. I fly em all,jets,helis,rockets...So a joystick is more versatile .

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>I would be interested to hear from real pilots on my point>about the landings though. Do ACES need to work on this, or do>I just need to work on my landings? :)FSX is very forgiving when it comes to landings. It can vary from aircraft to aircraft, but I've "walked away" from landings in FSX that I know darn well would have resulted in aircraft damage in real life (and yes...that's with "damage on" in FSX). I don't think that is a bad thing though. It allows "non-pilots" to experience virtual flying without the frustration of crashing too much. Keep in mind...if you get "outside the box" too far in FSX, you will STILL crash on landing (cause aircraft damage, etc), but it would be quite less often than in real life. So what if in FSX you "crunch" it every 100 or 200 landings? No biggie. THAT'S the difference between FSX flying and real-world flying, though. Crunching the aircraft every 200 times you land in real-life would NOT be very good. Crunching it ONCE in my 30-years of real-world flying would not be good at all. ;-)As for landing using "full stall" vs "fly it on" techniques in real life, there are times when you would use one over the other. Long runway with no strong wind gusts or turbulance? Full stall is the choice. Reason is it is the least demanding on the aircraft structure. There is no reason to put extra stresses on the undercarriage, etc, by "slamming" the plane onto the runway if you don't have to. On the other hand, given a stong crosswind with gusts, you really don't want the airplane flying on the "edge of the flight envelope" close to a stall 10 feet above the ground. A wind gust at this time can really ruin your day and crumple your airplane as it drifts sideways then drops out of the sky on you. This is when you would carry some extra speed and fly it on to the runway. You want "positive contact" with the wheels/runway while you are under control of the aircraft. Once the wheels contact the runway, it's yoke full forward to KEEP the airplane on the runway and avoid an unintentional takeoff again because of extra airspeed you carried on landing. Note we are talking about only 10 - 15 knots extra speed...not 40 or 50 knots here. You want to carry a bit more speed to avoid an unintentional stall in case of a wind gust, etc. Here's the thing about FSX vs real flying. If you take real world pilot lessons, you will learn about many different types of landings...regular full flare, short field, short field over a 50-foot obstacle, crab control crosswind (wings level), slip control crosswind (wings not level...one wing "low" into the crosswind), etc, etc. If you are a real world pilot, you can do ALL of these in FSX. If a non-pilot FSX user has never taken real flight lessons, they probably don't know about most of them, or how to PROPERLY do them, and NEVER use them in the sim. In FSX you CAN simulate all of them quite well. In FSX, if using a crab only crosswind technique in a Cessna 172, you will normally not experience any "bad things" happen to you if you don't kick out the crab angle prior to touchdown. That's cool. But in real life, if you don't kick out the crab angle before the wheels hit the runway, you may be in for a very expensive repair bill for your airplane (assuming you walk away from the "controlled crash" that you just did!). ;-)FalconAF

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Falcon:You'd get the smack with the wet noodle if you did that with me as your instructor! :-) "No stall horn no land", small GA aircraft regardless of wind conditions.A full stall landing is a requirement each and every time in the vast majority of small GA aircraft regardless of runway length or width or wind conditions. 2500ft runway, 12000ft runway, doesn't make a difference.You don't need to hold the aircraft at 10 feet to bring it to a stall, you simply begin your flare at 10 feet and stall the aircraft on your way down to the runway. Floating down the runway at the knife-edge of stall while floating is a very newbie thing to do. Besides a full stall while still at 10 feet will make for a very miserable landing whether you are in a Cessna 172 or a B747. (and the maintenance guys will hate you) :)For a x-wind, gusty or reported windshear approach you can add vref+wife+mom as appropriate however you MUST come across the fence at ~VREF. Why? A Vref+10 to 15kts landing will mean that you will float on flare (remember you MUST flare and hear the stall horn) since you will be well above stall speed. For instance, if Vref is 65kts, and you know that your rotation speed is 55kts then you try to land at 70-80kts that will mean you will land out of the touchdown zone even if you aim for the numbers. Of course you can force it down...which is bad, especially in aircraft with shear-pins on the landing gear. You NEVER fly aircraft like a c172 to the ground. Even with a no flaps landing, you will still land to the sound of the stallhorn because without flaps your stall speed is much higher therefore the higher speed is appropriate but the technique doesn't change.Also, you want to keep backpressure on the yoke after landing as a practice. A full stall landing means that the aircraft will no longer fly, so holding the yoke back won't make you take off again, however, you want to keep pressure off of the nose gear because many GA aircraft's nosegear will start to vibrate at higher speeds.A cross wind won't blow you off of the runway with a proper landing technique. The goal is to land at the right speed, and flare so that you don't float and once you pull pack power as you come over the fence, stall comes quickly and uneventfully each and every time. For instance, full flap, power of stall practice, the goal is to replicate landing. The goal is always to stall at a give floor altitude...failure to achieve a stall...failure to get your PPL. In an airliner ALWAYS fly the airplane to the runway. In a C172 NEVER fly the airplane to the runway. :-)Regards,Mike T.

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Mike,LMAO! OK, first things first...you are absolutely correct from an Instructor's point of view. 1. I don't ever plan on stalling the aircraft at 10 ft AGL. Yeah, the maintenance guys would hate me for that. Ideally, the stall will occur like you said...with the stall horn screaming at you just as the wheels touch the ground. Ideally...and most of the time it IS like that if done properly.2. And I'm not recommending making "carrier landings" with a C172...with no flare at all...either. The maintenance guys wouldn't appreciate that too much either.But in a true wind gust/wind shear situation, carrying just VREF over the boundary can get you killed. IF there is enough runway, a little extra speed over the boundary might be the thing that saves your neck. You can bleed it off during the flare without hanging the airplane by the prop. And if you encounter a downburst over the boundary, you might be able to save the day.The type of things I mentioned above were not intended for "normal ops" type of landings. In extremely gusty conditions, or where there is the possibility of wind sheer, I'm carrying more speed approaching the boundary, and will bleed it off to get to the "ideal" landing configuration once over the numbers. Would I recommend a Student Pilot do that? Nope. A Student Pilot shouldn't be flying in those kind of conditions to begin with.And I never push the yoke forward so that the nose gear slams onto the runway. I DO push it forward enough to make sure I don't rotate airborne again, though. With proper aileron control and rudder use, this maintains the track of the aircraft down the runway until excess speed bleeds off and I can lower the nose without damaging the nose gear.

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