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I am struggling to get users to turn this off, and they break the mission and rules that the mission designers spend a lot of time on. Why did this even get added? May we ask that this be removed?

Hi everybody, this topic is intended to clear out some misinterpretation regarding structural strength of simulated airframes here in DCS. During my evaluation and testing of simulated modules I have encountered certain damage model behavior that I found not to be inline with industry specifications and standards, historically and current, respectively in cases of ultimate load excess leading to catastrophic failure on wing structure, partially or in full. As an examples, I point to the occurrences of catastrophic wing disintegration in case of F14, F5, JAS37, MiG21, Su27, J11, Su33 etc. in cases of exceeding nominal limitations given in pilot manuals that occur instantly without prior warnings. My professional background covers field of structural evaluations of mechanical structures in high load conditions with application of crucial factor of safety that is applied on high stress elements of design with respect to fatigue impact on strength degradation over the life span of any high risk mechanical construction that aims to preserve design itself as lives of operators involved. Being involved in such evaluations, I find factor of safety the most important element of design that ensures design itself to be safe even after exceeding defined limitations in user manual in certain conditions. Thus, I will give some brief insights on allowed ranges and consequences of exceeding limitations not stated in manuals. At first, the observed behavior of named modules do not represent real life performance. The initial state of fresh spawned module is projected to be factory rolled state, meaning that there is a minimal work hours accumulated on airframe, theoretically. That implies that the state of structure is at peak strength without any developed structural imperfections and potential seeds of catastrophic failures. The most important structural degradation comes from fatigue induced cracks that are initiated and developed during life span of airframe within work envelope with higher expectancy towards end of life. In practice, that means that initial strength of airframe is, based on fatique evaluation, multiplied in such manner that, within nominal operational limits, able to withstand forces and moments induced on critical elements that keep the design safe on point of reaching end of design lifespan. Initial design safety factor is, founded by FAR, in range of 1.5 FOS(Factor of Safety) for civil aviation projects. Keep in mind that civil aviation designs are not expected to withstand battle damage of any kind but only environmental threats that include rough weather, turbulence and stress cycles induced mostly by landing shocks. Thus, military aviation projects are designed in such way that is mandatory to expect higher values of structural loads and performance limitation impact. As stated by FAR, as historical reference, in practice, that would imply that 9G civilian aircraft is safe to withstand 13.5G ultimate load stress without entering plastic, permanent, deformation of geometry. The ultimate load criteria is to be satisfied in time frame of not more than 3 seconds without plastic deformation assuring the geometry of airframe to return to initial state. That observation is based by FAR, simplified for initial reference. The MIL standards are product manufacturer's specific and are not standardized globally. Those designs do imply structural strength requirements that that exceed civil aviation in many areas simply because of nature of design and operative environment. So, this post is mostly intended to Module Developers, booth to ED and subcontractors, to revise the state of catastrophic failure occurrence in their modules as those practices do not reflect the nature of design they try to accurately replicate in DCS. If referring to pilot manuals, those limitations are intended to preserve airframe in full life cycle span, which means that initial state of fresh airframe is, based by fatigue evaluation, at least in 3-5 FOS range. Taking the lowest state into account, fresh 9G airframe should be able to withstand 27Gs without inducing structural catastrophic failure as wing separation is by nature. Nevertheless, this number might appear overrated but the industry does prove this to be the case as this is basic fatigue requirement and those same fatigue evaluations are expedited in at least the double lifespan working cycles. During that evaluation every weak spot is evaluated and reinforced to compensate possibility of occurrences of cracks that might lead to most undesired outcome. Keep in mind that military airframes, intended to be operational at high mach numbers, do have additional scopes of concern as thermal impact on weakening of structure, density fluctuation in airstream, as much as raw size of airframe aggregates bending moments on wingbox that grow exponentially in respect to length of wing against wing root chord length. My conclusive standpoint is that all involved should redefine the limitations on airframe structure and allow higher margin of safety that should be applied on simulated modules in addition to safety limitations extracted from pilot manuals. The most ideal presentation of structural failure should be presented in a way that, in cases of exceeding nominal limitations, pilot should be warned of incoming catastrophic failure in progressive manner starting from indicative sound (bumps and twists), rivet/bolt loosing and popup(damage module texture), control surface/flap separation (su25T example), permanent plastic deformation (extracted from wing flex feature) with aerodynamic performance degradation and ultimately wing/control surface separation leading to catastrophic event as loss of wing or portion of wing structure is. By rule of thumb the minimal FOS should be around 2 meaning that fresh 9G certified airframe should have to be subjected to at least 18G of force for catastrophic failure to occur and progressive cycle of damage should occur at FOS of 1.5 starting form 13.5G on referenced airframe above 3 second load condition. Thank you for your time. I do expect the corrections of this behavior to be accepted and implemented on future updates based on tools and methods available, but for a start, limitations should be set at FOS of 1.5 without entering permanent deformation on lift surfaces. Regards, J.