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Dondo

Depicition of Turbulance

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I loaded the freebie C152 from FSInsider. Installed without issues. Trimmed and took off using "real" local weather 50mi visibility, 11knot wind. No problems.Once up and away there was some light turbulence. Here is where I have a problems, not with the C152 (I think) but FSX. The aircraft would quickly move slightly to one side and then the other with a short space in-between the movements. Fine, but the movements were very obviously simple linear changes in heading. By that I mean, air is elastic plus an element of inertia exists. You simply cannot move things in a linear fashion. There is a ramp up in speed and a decay period. In FSX this does not appear to exist. Instead turbulence induced movements begin at a set speed and then suddenly stop. If a gust of wind hits an aircraft wouldn't it take some short time period to begin moving rather than instantly beginning its displacement? Then once the gust begins to cease the movement would slow and eventually stop. Instead I see an instantaneous stop of the aircraft's movement. On a graph there would be a slope upward and an almost flat top until the gust stops where inertia causes a downward slope.I may be way "off-base" and possibly have some setting wrong in FSX but turbulence in FSX, on my system, seems to be wrong.XP/SP3 44fps locked at 25fps.Regards,Dick BoleyA PC, an LCD, speakers, CH yoke

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Sounds like you are comparing turbulence in a big jet compared to a 152.Think of it like a boat in water. In rough seas a rowboat gets knocked around faster and worse than a huge ocean liner.A 152 is about as small as you can get.. :-)GeofaMy blog:http://geofageofa.spaces.live.com/

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I am not here to defend fsx's turb or wind depiction as it can be pretty bad but it it waht it is.Activesky is better overall but still had some major bugs.But YES. I have hundreds of hours in all the high wings Cessnas and smaller planes in general.I have been so beat up and tossed around that i felt like I had been in a washing machine.i once flew a 150 from Columbis sc to Daytona that my fbo sold to a flight school.It was during the summer and I dodged thumderstorrms the entire trip.i thought the plane "and me" were going to come apart at any time.You can hit these instant plus minus 500-1000 ft drops and hear the plane groan and metal twisting.I learned to always stay good n strapped and never have any loose objects in the cabin.I was flying a 402b model twin cargo into atlanta and although 25 miles from a big storm were getting beat up bad.These planes had crew doors that opened vertically and one flew open. The guy reach up and grabbed it and at the same time we hit another pocket.It hyperextended his arm and dislocated his shoulder.I was also on a 777 going to London up around the mid thirties when out of nowhere we hit a airpocket. Things actually went airborne and i became weightless.:-jumpy Bins flew open,people screamed, the whole deal.Sorry about the bad tying but I bough one of these MS " natural ergonomic keyboards that has the strangly raised keypad.My typing was bad enough and why I bought this is any bodies guess.

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If you fly in a 152 in the real world you can get the heck knocked out of you in turbulence. I would indeed compare it to a rowboat in rough seas.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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Ok, here I go: My guess is that you have read somewhere that this type of keyboard reduces turbulence :+ Even having been produced on an ergonomic keyboard, your info was nice and interesting reading though.Jos

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To me, it looks like we are attacking this issue from many different angles,and I think I can sum things up:1) Weather in FSX is generated in "cells" that surround the weather stations. The boundaries between cells can be very abrupt. If you fly along one of those boundaries, you can expect winds to come from anywhere.2) There are ways to work around this problem, using add-ons as mentioned above. People also reccommend paying the registration fee for FSUIPC to get the weather smoothing function.3) Turbulence in FSX does seem to me basic and tame compared to real-life flying in small aircraft. Don't get me wrong: I am a professional passenger, but even a passenger will understand turbulence in the Rocky Mountains in a small aircraft. Think of a long roller-coaster ride that lasts for hours where the tracks are made out of rubber bands and rocks. Then again, most of us fly our desks. In that environment, it's hard to create the white-knuckle intensity of a flight that is being held together only by the skill and dedication of a brave flight crew. Jeff ShylukAssistant Managing EditorSenior Staff ReviewerAVSIM

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For me one of the improvements in fsx over fs9 is the turbulence-it isn't perfect yet but much closer.A good question is why does maneuvering speed higher when you have more weight and lower when you have less? Again-the op mentioned the C152.The boat analogy is why. More weight-more stable...less weight, less stable.I took a friend for a ride a couple weeks ago in pretty gusty moderate turbulent conditions. His first comment on landing was he could not believe how abrupt the turbulence was-and especially the yawing motion (which of course is worse in the back seat).This was in a 5100 lb aircraft-now imagine what would have been in a light C152 of 1300 lbs. If the jets are reporting light turbulence-you can bet it will be a different report in a small aircraft-something you notice in your preflight briefing.GeofaMy blog:http://geofageofa.spaces.live.com/

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Turbulence in FS hasn't ever been all that accurate in my opinion, though when encountering mild turbulence at least I've found it fairly realistic and kind of fun. The only real problem I've ever had with FSX's implementation is that once moderate or heavy turbulence hits it tends to keep affecting the aircraft long after it has passed, which is strange. Quite often turbulence will drop a wing momentarily but in FSX it just keeps trying to drop the same wing for up to a minute or so after the jostling is over. I never fly with it on for that reason.As for real world experience I've hit my head so hard, and so many times, on the roof panels of Arrows and 172s I'm surprised I have any working brain cells left. :)Another major factor in the intensity of constant turbulence from an airliner pilot or passenger's perspective though is aeroelastic whipping, especially noticeable if you're riding business class or in the tail. The further you're seated from the CG the wilder the ride. ;) This very problem is what led to the addition of electronic ride control vanes on the nose of the B-1B. The pilots would just get pummeled in low level turbulence at 500 kts without them haha.-mike

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A lot of replies have dealt with weight here - the other factor is speed. If you are jetting along at 500 knots, your inertia to maintain that path is very strong - especially if you are a large heavy jetliner. A plane going slower requires far less force to knock it off its projected path.Remember our high school physics - force = mass x velocity squared. The impact of higher speed it going to be exponentially greater than weight. I know this is not a formula for calculating inertia (I was a history major), but it still serves to illustrate the point. Colin WarePortland

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I have found that real world weather in FSX doesn't work right and don't use it. Wind directions suddenly change up to 180 degrees (apparently when moving from one cell to another) which causes the yawing. Consistently, I experience a 180 degree wind direction change at a certain point when taxiing across my home airport with real weather. This is not a problem with user-defined weather, and it is also not a problem with ASV6.5 real world weather (but I have other problems with ASV6.5 in FSX).ArtBiostar TF560-A2+, Athlon 64X2-6000+, 4GB RAM, Geforce 8800GTS-320MB, 500W PSU, 250GB HD, FSX(SP1-SP2), Audigy SE sound, Vista Home Premium 32 bit, CH Yoke & Pedals, 22" WS LCD monitor

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>I have found that real world weather in FSX doesn't work>right and don't use it. Wind directions suddenly change up to>180 degrees (apparently when moving from one cell to another)>which causes the yawing. I've heard about the problem, but I guess I don't fly high enough to encounter it. I use Real weather quite often.As to turbulence; yesterday (real world) is was bad enough, that I couldn't even change radio frequencies for a bit.BTW--- I do like those mountain wave rocking motions that a present in FSX.L.Adamson

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The computer is a modest 2.5ghx e4400 with a nVida 8600-256mb video card. If there is any secret it is that I "fly" a lot with Dreamscapes photo scenery so Autogen is not possible (big savings) and I rarely use it with synthetic scenery. Traffic is also off except when I want to see what happens in active airport areas. Other scenery type sliders are max except for water which is min. After the usual struggle searching for the "magic settings" (cfg & elsewhere) I accepted the price/performance/slider ratio I could afford and live with it.As to the turbulence, an addon may be the answer where it can manage the weather environment in more detail. I should probably spring for a flight at the local airport (KLBE). Have to save up for a supply of barf bags. Thanks for all the comments. While not perfect, FSX does seem to have a consensus that it is reasonably close and just needs a good addon.Regards,Dick BoleyA PC, an LCD, speakers, CH yoke

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I don't have much to add to this discussion, but I thought I would just comment on my experience. I have about 30 real world hours in a 152 and close to 100 in a 172. ( only had my PPL for about a year) I fly in Kansas. In FSX, I typically set the weather to moderate turbulence. As was stated before, it doesn't "feel" quite right in the sim, but it is a little more accurate to Kansas flying. I have never experienced severe turbulence as I am very much a fair weather flier (Wind less then 22 kts typically). Kansas always seems to be choppy and windy while flying. At least when I fly it does. TrackIR seems to makes the turbulence look a little more realistic I think. The plane moves and shakes around but your head kind of stays looking forward.

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