GWMobile schreef: > The original post quoted below exemplifies why I beleive it is a mistake > to ever have crash detection for water in a flight sim however let me > lay it out simply. > > 1. Anyone who lands on water in a flight sim knows they are doing it. It > is highly likely they WANT to do it - ie have a float plane or want to > ditch. > Setting a crash default is silly. It forces people to not be able to do > what they want and it isn't realistic. > > 2. In reality all water is in fact landable even in > a non float plane. It simply acts like extremely mushy ground. It should > be treated like land and have a large drag component. In fact all ground > should have a drag componenet so pavement, grass, snow, and muddy > runways can be modeled - water should just have a very large drag > component. This would more properly simulate takeoffs and landings on > ground on water or snow or hard ground etc.. > > Water should be treated like land - period. Any crash detection should > ONLY result from the speed of vertical decent during landing but frankly > even that should be selectable because all planes have different > undercarriage survivability (and again you will end up limiting > people.) > > We should rememeber that water crashes were an error result caused by > limited flight sims of the late 80's. > Water "Crashes" in flight sims originated > When BAO marketed by Microsoft added water crashes early on and it was > an ENTERTAINMENT feature - it caused an exciting sound and forced a > restart. > IT WAS A BAD IDEA THEN AND HAS BEEN CARRIED FORWARD BY HABIT RATHER THAN > REALISM ever since. It was a cheap stunt partially caused by limited > contact feature routines (there was only one contact routine - crash!) > in the EIGHTIES whether between buildings, other vehicles or water plus > I suspect the desire of Microsoft (or BAO Bruce Artwick) to create > excitement and a "feature" for amateur flyers. > > One should NEVER CRASH simply because one lands in water. One should be > allowed to land in water anywhe > Anyone landing on water is chosing it. He either has a float plane or > has decided he wants to put his cessna down ignoring all reality or > simulating a ditching. The sim should on default allow it. > > One should ONLY crash when the rate of collision in the direction of > contact (in landing that is vertical speed) exceeds any reasonable > impact whether it be with a building, other aircraft, or in a landing. > That should be modeled with seperate default factors for vertical side > and frontal impacts - especially vertical- that an aircraft model file > will carry modifiers for so different aircraft structures survivability > can be slightly modeled without full structurally analysis. > This way a jungle jumper or bush plane could have say a 3 in the > vertical modifier key so the sim could calculate that the bush plane > won't "crash" unless it's vertical touchdown (rate of descent in > meters/sec) component is more than 3 times default. > If you want to get even more accurate landing without structural > analysis, "crashes" (unrecoverable landings) should be modeled by > calculating the gross weight including remaining fuel times the vertical > component at touchdown times the aircraft models factor modifier. > Anything beyond that and you need to start introducing structural > analysis in the sim which is a whole different ballgame. > George > I like the idea of having a configurable set of crash conditions. The defining factor in any crash detection is the energy of impact, which is indeed a function of the "landing" weight and the velocity vector in the direction of impact (e.g. in landing, that's down, but one could also make those conditions hold in the lateral direction to prevent unintentional crashes which may be caused by very slow "nudges" into other aircraft or buildings. The maximum impact energy could be defined as a parameter in the FDM description, which doesn't require a real-time structural analysis. If we want to do it all-the-way right, we could define the impact energy per contact point, for example, an An-225 has a lot more wheels than a 747 and that's also the reason it can land on grass and other surfaces, because it's impact forcce is divided over a larger surface area.
The second thing is what to do with a crash when it occurs: display a dialog with analysis, reset, or ignore? Needless to say the default MSFS behavior (stop and simply display "CRASH") is pretty useless. Most newbie flyers will want to fly with the crash detection off anyway, and experienced users will probably cause intentional crash situations for testing or experimentation purposes or for re-enacting actual crash situations (like crash investigation). ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
