I made a descent in the PMDG B1900D (same thing has happened with the Cessna) and got a warning 'overspeed', then a picture of the plane from outside and the message 'plane overstressed' and flight ended.Why can this happen just for flying to fast? Exactly why does the plane break up? Is this realistic?I mean airliners can fall several hundred feet in turbulence and the wings are strong enough to hold.

Why can this happen just for flying to fast? Exactly why does the plane break up? Is this realistic? I'm no pro on aircraft stress and how much it can withstand, but I'll give them a shot.Why can this happen just for flying to fast?Aircraft are built to withstand things within a certain limit. The Cessna 152 I fly, for example, has a Never Exceed Speed (Vne) of 149 KIAS. You should never pass this mark, specified as a red line on the airspeed indicator. Right before this red mark on the airpseed indicator is a yellow arc which is from 111-149 KIAS. You should never enter this arc unless the air is absolutely smooth, and if you do enter it then, do so with extreme caution. If you go into the yellow arc while there is turbulence, you most likely suffer some damage ranging from missing rivets to broken control surfaces. If you pass the red mark, Vne, your pretty much dead. Your wings would probably rip off, followed by your empennage (tail assembly) and soon enough... lights out.Exactly why does the plane break up? As stated above, the aircraft passed its designed structural limits. After that point is breached, systems and controls will fail.Is this realistic?Yes to a certain extent. If it gave you an "Overstressed" warning a second after overspeed came on, then no- it is not realistic. It would take a bit longer than that for anything to actually happen, or at least I think it would.Jason :-wave EDITED for a couple grammar mistakes. ;)

Just to expand on this a little, there's several reasons why things can break when you exceed Vne. The faster the airflow over the wings and tail surfaces, the more lift that's developed. More lift means more force. The increased lift is bending the wings up with more force. Many in-flight breakups are caused by the wings failing upward. Or, sometimes the horizontal stabilizer can fail downward, which obviously causes an immediate loss of control.Also, increased airflow over control surfaces can cause flutter, quickly leading to failure of the control surface.

Hang on Guys :-)No the way MS handles overspeeds or things like gear extension limits isnt correct.If an aircraft has a VNE of 200 kts do you think at 201kts the thing is going to fall apart. Flutter or have a multitude of other problems?Of course not. If handled very gently and in smooth air an aircraft would cope with way above VNE because the manufacturers build in a huge margin.infact In the Citation it is very easy to bring on the overspeed at low level in level flight.Gear will take far more than the published speeds as it is usually the gear doors which cause problems not the gear itself.On the flip side it is easy to overstress an aircraft below VNE in the wroung conditions or when making abrupt control inputs.I am not suggesting in any way exceeding published limits real world and strictly adhere to precise flying myself but I do find the failures in MSFS a bit "gamey" and turn them off ;-)Also outside the published envelope you are very much in the realms of "test pilot"Peter

Yes Peter, I know there's margin built in. That's why I said "can break" instead of "will break". I was just trying to describe what happens when you cross the line, wherever the line may be.Also, I didn't try to explain yield vs. ultimate failures. In general, the aircraft structures will permanently deform well before they break. That renders the plane unairworthy, but at least it allows a safe landing.Haven't seen you in a while. Glad to hear you're still logging Citation time.

It is unrealistic to use Flap 40 at 300kts, extend landing gear at 350kts, etc, etc, etc. FS2004 can't affect the aircraft as it should, we have to fly under the operational limits for simulation reality, not for FS reality :)Ulisses

I've noticed (;)) that with the PMDG B1900D, that "overstressed" condition can occur by redlining the RPMs for too long as well. Since you saw the overspeed warning, this was probably not the case, but is something to watch out for...Best,sg

Of course it's highly unrealistic that any damage would appear if your flying in smooth air and a few knots above Vne. But that's the way FS handles "above the limit operation". It's the same with maximum G's. The must anoying thing to me is that FS pauses the simulation. It should keep on running unless I tell it NOT to. That's why I've turned the plane overstress option off.I generally stay withhin the limits, but hey, its a simulation so go for it. :-bigangeljust my two cents,Claudio.

>It is unrealistic to use Flap 40 at 300kts, extend landing>gear at 350kts, etc, etc, etc. >FS2004 can't affect the aircraft as it should, we have to fly>under the operational limits for simulation reality, not for>FS reality :)>>Ulisses Ulisses >under the operational limits for simulation reality, not for>FS reality :)That is why I turn damage off because real world I dont damage aircraft.We fly within the flight manual limits.But the point made here is that people who are imperfect do make mistakes and for that reason there is a large margin built into these limiting speeds.For instance an aircraft may have a G limit of -1.5 to + 3G but when tested to destruction the wing may fail at +9G or higher.For your wings to break off if you pull +3.1 isnt real.An aircraft can go through VNE by 30 kts if flown and recovered gently but you can pull the wings off at 30 kts below VNE if you abuse the controls ;-)So for me its a pointless exercise having accident damage on as in 20 years of flying I still havent collapsed the undercarriage on landing but I have in FS ;-)Peter

>Yes Peter, I know there's margin built in. That's why I said>"can break" instead of "will break". I was just trying to>describe what happens when you cross the line, wherever the>line may be.>>Also, I didn't try to explain yield vs. ultimate failures. In>general, the aircraft structures will permanently deform well>before they break. That renders the plane unairworthy, but at>least it allows a safe landing.>Shouldn't the problem be more of the plane getting out control before damage occurs?

ClaudioI am against things which I see as "gamey gimmicky" failures but I am all for the simulation of problems which occur and which the Pilot has to identify and deal with as part of his day to day life.Aircraft and their systems do go wroung and part of the Pilots skills are dealing with those problems and completing the flight to a safe outcome.He has to identify a problem find the cause and correctly respond to it.So yes I am all for more accurate engine failures as ive had three real world. I am for more accurate systems failures, gear extension and retraction failures, communication failures, navigation failures.I am all for accurate "icing" behaviour and the problems that causes.The list goes on but the Gimmick failures like wings falling off. Gear collapses etc which arent even accurate to real life then????Peter

"I've noticed (;)) that with the PMDG B1900D, that "overstressed" condition can occur by redlining the RPMs for too long as well."This can happen with default aircraft as well actually. Not exactly realistic - I doubt the airplane would explode in mid-air if I'm in an emergency and need to keep full power for a bit longer than normal to clear some obstacle.

PeterI'm only fly small ga A/C's so I don't know a lot about system failures etc. I just wanted to point out that just stopping the sim can't be a solution! And as it is a sim, I'd like to do stuff u can't in real world because it's to dangerous. I'd like to see the wings bend upwards as gload increases at least. The same with turbulence.Maybe the computing power isn't far enough, but an aircraft model that isnt just eye candy, but an object that reacts physically correct to its enviroment would increase the "as real as it gets" feeling to huge extent. regards,Claudio

ClaudioI am with you on that but then you would have to model all the dynamics and stresses involved to get an accurate reaction.Just to have the wings break off just above VNE for me is "gamey". Maybe a question of "if you cant do it properly dont do it at all"Icing is another good example which to me is gamey because the full effects of icing are not accurately modelled.Peter

I fully agree with you.There are so many things that could be improved, that I don't know where to start at (and where MS will...). To me true physics are the most important area regarding flight simulation. But as long as FS is named a "game" the developers will more likely concentrate on adding eyecandy than on "stuff" you can't see. If I'm right it wouldn't be possible with gmax modelling anyway. So all aircraft had to be rewritten. And I don't expect that to happen.The conclusion: We have to wait:-violinHopefully we'll get it sometime,Claudio.