Dudley HenriquesInternational Fighter Pilots FellowshipCommercial Pilot. CFI RetiredI('m researching an FS9 issue and need some feedback if I can get it.I need real information and first hand opinion if possible from some of you sim folks more into the guts of the simulator than I am.Here's the issue.I have an ongoing issue with ADD ON'S ONLY, that involves the following;If the airplane is flown from one airport to another, in other words to certain airports, if the add on is landed normally, and then as you are taxiing after landing, you cycle views through tower, spot, and back to cockpit, when you hit spot in the sequence, the airplane jumps hard on the gear and settles in again on whatever surface it's taxiing on. This doesn't happen if you are flying a default aircraft.I'm trying to isolate the cause of this issue. It doesn't seem to be hardware related in any way. It can be replecated with several video drivers. One developer has suggested that it's AI aircraft related and is a problem ingrained in FS9.Can anyone shed some light on what might be causing this issue?If someone has an add on and wishes to replicate my test scenario, take the add on and fly it from KILG to Summit Airport in Maryland and cycle the views after landing while still on the runway and see if the airplane jumps high and back down again on the gear after you go through tower view and than hit spot view.I need input on this issue from all available sources if possible.Thank you very much.

Hi Dudley A number of posters to these forums have reported the bouncing aircraft issue and I also suffer from this occasionally. I think (and this is just my suspicion) that it relates to the way FS loads terrain. FS loads one terrain mesh level of detail (LOD) and then steadily loads more detailed LOD`s as resources allow. I`m not sure how familiar with the FS terrain structure you are but the substrate of all FS scenery is the terrain mesh - a grid of spot heights which the ground textures are draped over. The LOD is simply the spacing of the spot heights which make up this grid. Apologies if I am teaching your Grandmother to suck eggs here! At airports where there any kind of scenery layer issue (at some airports the aircraft actually sits at the terrain height rather than the taxiway/runway height), when the sim loads up the next level of detail, the a/c`s elevation changes fractionally, but instantaneously, causing it to leap into the air. I suspect the aircraft design may play a part, as like you have found, not all aircraft are affected. Perhaps the dynamics of the suspension is a factor too.Unfortunately, I have found no resolution for this issue, I am just providing my thoughts on what the cause may be.I hope this is of interest to you. Your recent series of posts about high performance piston flying have been very interesting. Thanks for sharing your knowledge with all of us here.RegardsRottenlungs

>Hi Dudley >>A number of posters to these forums have reported the bouncing>aircraft issue and I also suffer from this occasionally. >>I think (and this is just my suspicion) that it relates to the>way FS loads terrain. FS loads one terrain mesh level of>detail (LOD) and then steadily loads more detailed LOD`s as>resources allow. I`m not sure how familiar with the FS terrain>structure you are but the substrate of all FS scenery is the>terrain mesh - a grid of spot heights which the ground>textures are draped over. The LOD is simply the spacing of the>spot heights which make up this grid. Apologies if I am>teaching your Grandmother to suck eggs here! >>At airports where there any kind of scenery layer issue (at>some airports the aircraft actually sits at the terrain height>rather than the taxiway/runway height), when the sim loads up>the next level of detail, the a/c`s elevation changes>fractionally, but instantaneously, causing it to leap into the>air. I suspect the aircraft design may play a part, as like>you have found, not all aircraft are affected. Perhaps the>dynamics of the suspension is a factor too.>>Unfortunately, I have found no resolution for this issue, I am>just providing my thoughts on what the cause may be.>>I hope this is of interest to you. Your recent series of posts>about high performance piston flying have been very>interesting. Thanks for sharing your knowledge with all of us>here.>>Regards>>Rottenlungs Dudley HenriquesInternational Fighter Pilots FellowshipCommercial Pilot. CFI RetiredThank you for an extremely informative answer. What you have said fits perfectly with what one developer has told me concerning the suspensions. Also, I've noticed that at the airports where this seems to happen most of the time, as the cycle of views goes through the tower view, the scenery loading times are somewhat long and fractionalized as well. Also, the airplane itself is missing totally from these views...just trees...and surrounding terrain.I've thought for some time that it has something to do with the loading in tower view but in my ignorance of how things work in the sim, naturally I couldn't put a finger on it.Your post has helped me understand things a lot better.It's a shame nothing can be done about it, but perhaps considering MS is aware of it, they will address it in the next version.Thanks again,DH

Hi there. It is curious that you say only add-on planes do this.I did have some Lago add-ons that jumped about or sank their tails into the ground for no apparent reason(to me anyway)when stopped, but why don't the default planes do this? Well, perhaps they do, but I've never noticed.My 2 cents worth!

>Hi there. It is curious that you say only add-on planes do>this.I did have some Lago add-ons that jumped about or sank>their tails into the ground for no apparent reason(to me>anyway)when stopped, but why don't the default planes do this?>Well, perhaps they do, but I've never noticed.My 2 cents>worth!Dudley HenriquesInternational Fighter Pilots FellowshipCommercial Pilot. CFI RetiredI've never had a default aircraft do this, only the add on's. I think another poster has a handle on it. It has something to do with the way the textures load in the cycle sequence and the gear suspension on the add ons.I've been experimenting a bit with it. The two airports that I've been using are new Castle County as the departure point and Reading Spatz Airport a few miles away as the destination.I've had jumping on two add on's after landing at Reading and cycling the views, and no jumping when doing the same thing with a default Baron.I have noticed two things. First, if I deleted the saved flight that was doing this as well as the previous flight if it was the same aircraft, then created a new flight and went again to Reading, the jumping wasn't nearly as bad; ALSO, I could eliminate the jumping almost altogether by using shift+S to cycle the views instead of the stick assignment for shift+S (cycling views) that I had been using to get the jumping.So I think it might have at least something to do with assigning that function to a controller. If you change the default spot view of the airplane and move around in the spot view with the hat to get a closer look at the airplane, I think something might be getting corrupted in the stick programming.Just a wild guess.

This is a problem that only seems to affect a few add-on planes, from what I've noticed. The RA Spit will bounce a little as views are cycled, and the POSKY 747-400 will frequently bounce severely on loading into the flight; infact so badly it will cause the nose gear to collapse!It almost seems as though the sim renders the scenery and then just 'drops' your aircraft onto it! Maybe it's also related to add-on scenery, whereby the sim expects to place the aircraft at a particular default altitude, but the add-on scenery differs by a couple of feet?

The best solution for this problem is to load a flight with the default 172 (in fact, many advise that the default flight itself... 172 at KSEA... should be loaded) first, and then change the aircraft to the add-on you choose. I always start all of my flights with the default 172 then change to the whatever add-on I really want to make the flight with. Never have any problems with bouncing birds.Hope this helps,Greg

Hi DudleyI suspect the higher the peformance of the PC, the less noticeable this effect would be. When we have 5GHz machines with 1Gig video cards it will be but a memory.You may find that letting the sim 'draw breath' before cycling the views helps. The sim loads the area in the eyeline first, and then works on the remaining areas as resources allow. If I rush my PC (which is a little long in the tooth now admittedly) then I will get not only the odd bouncing aircraft, but regular temporary texture drops and blurry textures. By giving the sim a chance to do some loading before I swap the views the problem is mitigated, to a degree.RegardsRottenlungs.

>This is a problem that only seems to affect a few add-on>planes, from what I've noticed. The RA Spit will bounce a>little as views are cycled, and the POSKY 747-400 will>frequently bounce severely on loading into the flight; infact>so badly it will cause the nose gear to collapse!>It almost seems as though the sim renders the scenery and then>just 'drops' your aircraft onto it! Maybe it's also related>to add-on scenery, whereby the sim expects to place the>aircraft at a particular default altitude, but the add-on>scenery differs by a couple of feet? Dudley HenriquesInternational Fighter Pilots FellowshipCommercial Pilot. CFI RetiredIt also seems to be an intermittent issue as well. I can alter the severity, and in fact, make it stop for awhile by deleting the saved flight that's doing it and reloading the same flight again fresh.I believe, as you do, that the scenery loading is related to it somewhow.DH

>The best solution for this problem is to load a flight with>the default 172 (in fact, many advise that the default flight>itself... 172 at KSEA... should be loaded) first, and then>change the aircraft to the add-on you choose. I always start>all of my flights with the default 172 then change to the>whatever add-on I really want to make the flight with. Never>have any problems with bouncing birds.>>Hope this helps,>>GregDudley HenriquesInternational Fighter Pilots FellowshipCommercial Pilot. CFI RetiredNow THIS is interesting! I'm getting the bouncing from saved flights all starting at the same location....different aircraft each time as chosen...but all from the same starting point on the same airport all the time. I never have loaded the default flight, or use the 172 at all.I'd have to give this "fix" a little thought as how to use it without it being a PIA, as my weather settings are also affected for each flight I have saved.For example, I have a Mig 21 flight saved from my starting point as a day VFR flight...then I have another Mig 21 flight from the same identical starting point saved as a night IFR flight. By pulling up the default 172 as a single starting point, I'd have to reprogram each flight both airplane and weather wise every time I used the sim.I'm going to try this once however, just to see if it eliminates the bouncing on my machine.Thank you for the tip.If it works, perhaps with a little thought I can come up with a way to do it......like save the 172 in each weather configuration at the same starting spot, then just switch airplanes and go.This should keep me busy for a few hours at least. Thanks again.DH

>Hi Dudley>>I suspect the higher the peformance of the PC, the less>noticeable this effect would be. When we have 5GHz machines>with 1Gig video cards it will be but a memory.>>You may find that letting the sim 'draw breath' before cycling>the views helps. The sim loads the area in the eyeline first,>and then works on the remaining areas as resources allow. If I>rush my PC (which is a little long in the tooth now>admittedly) then I will get not only the odd bouncing>aircraft, but regular temporary texture drops and blurry>textures. By giving the sim a chance to do some loading before>I swap the views the problem is mitigated, to a degree.>>Regards>>Rottenlungs.Dudley HenriquesInternational Fighter Pilots FellowshipCommercial Pilot. CFI RetiredI'm running a high end Hypersonic gaming machine...at least it WAS high end last year :-)))) I think you hit it right on the head with the texture loading. I'm almost convinced that this is directly related to it.Did you catch the comments above by another poster about loading the default 172 and then changing airplanes? I'm going to give this a try, although I can't quite get how it would change anything with contact points for the add on's affected. This program does strange things, and it's a learning experience every day for me :-)DH

Yes, most developers recommend loading their planes over the defualt 172, but I believe that's primarily to ensure that the systems and guages load correctly. I think the problem is that so many of the add-on planes now use hidden guages and so forth to create or allow certain effects and these can sometimes cuase problems when switching from one plane to another.

>Yes, most developers recommend loading their planes over the>defualt 172, but I believe that's primarily to ensure that the>systems and guages load correctly. I think the problem is>that so many of the add-on planes now use hidden guages and so>forth to create or allow certain effects and these can>sometimes cuase problems when switching from one plane to>another. Dudley HenriquesInternational Fighter Pilots FellowshipCommercial Pilot. CFI RetiredI tried creating a new flight with the 172 and switched to the add on. Same issue...no change. I believe it might be a combination issue between the sim, the add on programming, and specific system configurations.It will probably remain an issue as long as it just concerns add on's as MS can't duplicate the situation close enough to get a benchmark.The answer will probably come from some savvy developer who finds a cure by accident and passes it on to the rest of the community.Until then.....boing......boing....... :-))DH

HI Dudley,As you know, the RAS Spit does occasionally suffer from this and I at first thought (and to an extent still do) that it is also related to AI traffic settings. I notice that on various aircraft which suffer bouncing, this effect is noticeably reduced when AI traffic is switched off.I too have noticed that it rarely happens with default aircraft.I feel almost certain that the MSFS team knows the root cause but so far I have seen no hints from them as to what the reason is.I do notice that the bouncing quickly settles down once the loaded aircraft is "established" and you have been taxiing for a while.I also think there is some relationship to different video drivers, the view you happen to choose and the AI activity at the airport you load.The comment above about scenery mesh elevations seems to make sense too.I have never seen more than a fleeting bounce and therefore it does not irritate me too much, but perhaps on other systems it is more of a serious problem.I hope someone comes up with a definitive solution.Kind Regards,Rob Young

>HI Dudley,>>As you know, the RAS Spit does occasionally suffer from this>and I at first thought (and to an extent still do) that it is>also related to AI traffic settings. I notice that on various>aircraft which suffer bouncing, this effect is noticeably>reduced when AI traffic is switched off.>>I too have noticed that it rarely happens with default>aircraft.>>I feel almost certain that the MSFS team knows the root cause>but so far I have seen no hints from them as to what the>reason is.>>I do notice that the bouncing quickly settles down once the>loaded aircraft is "established" and you have been taxiing for>a while.>>I also think there is some relationship to different video>drivers, the view you happen to choose and the AI activity at>the airport you load.>>The comment above about scenery mesh elevations seems to make>sense too.>>I have never seen more than a fleeting bounce and therefore it>does not irritate me too much, but perhaps on other systems it>is more of a serious problem.>>I hope someone comes up with a definitive solution.>>Kind Regards,>>Rob Young>>>Dudley HenriquesInternational Fighter Pilots FellowshipCommercial Pilot. CFI RetiredThank you Rob. This as well as your initial observations to me prior to this have been of great value.I'm still messing around with this thing trying different scenarios since I have an airport near to the one I use as my constant departure field that produces the bouncing.Today I tried the following between the two airports; departure is always New Castle County in Delaware, and the one near to that that produces the bounces after landing is Summit Airport in Maryland.I loaded the 172 and flew the few miles to Summit and landed. Then after slowing down on the runway, I cycled the views. Rock solid! From the 2D cockpit of the default 172, the views cycle on my machine instantly and with no loading lag.Then I switched to an add on that produces bouncing. After the aircraft had replaced the 172 on the runway, I again cycled the views. This time there was a noticable difference in the way the view loaded as the views changed. The spot was ok, but the tower view loaded in jerky phases and jumped slightly as it loaded. Finally coming back into the cockpit again, there was a triple jump on the gear....not extremely violent...but enough to let you notice it. :-)It's notable to state that so far, the flights I've been loading at new Castle have been initiated with the traffic set at 25%. I'm going to try creating a new flight with 0 AI traffic and duplicate the New castle to Summit flight again to see how that works.This is an interesting quest...finding this bug. Your input has been of great help. I agree with you...it's not really a biggie and it can be lived with easily.Dudley