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nickpike

How can you tune the afterburning effect???

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Hello thereThe aircraft.cfg post only the "dry" thrust values and fuel consumption.You can only say if there is an afterburner or not, but how can you determine the amount of additional thrust and fuel consumption??It is automatically colculated in the .air file??? and How can you tweak it???In several fighter I have if you shove the throttle all the way (for eaxmple the F-15 coral or the Kirk Olsson's F-16) you automatically enable the afterburner, this is done via a gauge right?? I think I found this gauge in the F-16 package but not in the F-15 (I found only a gauge to light the visual effect but not the actual afterburner) There is any other way to automatically kick in the afterburner??? I found no info whatsoever in the SDK documentation....and my impression overall is that with the standard Microsoft SDK docs you cannot go very far..even a lot of basic things (just for example: the max number of lights in the aircraft.cfg file, or the possibility to reverse the rotation of the propeller in the propeller section) are not even mentioned.It is just my impression or the Microsoft SDK kit is somewhat poor???Thanks for answering!!

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Hi,To start with your last question: Yes, most MS' SDKs are rather poor and certainly not complete; especially w.r.t. flghtdynamics.On the positive side: it's free, and a whole lot better then years ago :-)About the reheat/afterburner function:As you have concluded yourself, adding an afterburner visual effect and a "functional" (=extra thrust) afterburner are two seperate things in FS.Whereas a lot of addon aircraft have included a visual effect, most have NOT modelled the additional thrust/fuel consumption (which is configured in the .air file).Also, the way the afterburner is engaged varies per addon.Although most of them are gauge-controlled, there are two types of solutions for such gauge-control:- The simple one: AB engages automatically when the throttles (or N1) exceeds a certain value.- The more realistic one: the AB is switched on manually by the pilot, with the precondition being that full-throttle is already applied.If you want to know more, or how you can add AB thrust yourself to an existing addon, read the README of my latest AB-gauge version.File RCBac-10.zip in the library.Cheers, Rob

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Download C4SSTv3.zip. This is my aircraft and has AB modelled correctly for additional thrust and fuel burn. For example, the airframe number needs to be 66 (possibly others as well but this works). You can see from the XML gauges how the AB works, etc.cheers,nick

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Thank you guys for your suggestions!Rob your comment was extremely informative but it begs few questions..The afterburner_available=1 line is just a switch for the afterburner toggle variable right??? When you model an airplane from scratch (using for example the MS SDK when you have the aircraft templates) and include that line it doesn't get automatically created in the air file using some sort of pre-calculated formula in the table??? You necessarely need to open the .air file to include the afterburner effect "from scratch"??? Or MS create a "default" one that you can later tweak??When you include in the reference speed the max_indicated_airspeed and max_mach, your aircraft will reach that speed no matter what even if it is underpowered or FS is smart enough to calculate if you can really reach that sped based on your weight, size, aerodynamics and speed???What I mean is, if you put in that section mach 2 and 800 kias for a Cessna 172, it will reach that speed???!!!Last question is for the F-15 Coral: I check the static thrust value of the .cfg file and it says 19.000 lbs that more or less is the correct value for that engine "dry"At the same time I looked at the aircraft panel gauges (all in XML so are easy to check) and there is no indication whatsoever of afterburner toggling but only the visual effect.Still the plane get to mach 2.6, so where the developers decided to activate the afterburner thrust?? directly in the .air file??? And how you do that??Thank you very much for your answer!!!!Regards

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Yes, the afterburner_available=1 just indicates that the aircraft HAS an afterburner function; if 0, AB commands won't work.Normally this is set in the .air file as well, but if not there, you can edit it in the aircraft.cfg.There is NO default AB thrust in the .air file, so you always need to set this mach-AB thrust parameter yourself.The max_mach and _ias values in the aircraft.cfg have nothing to do with the actual performance of the aircraft; it's only used by FS to give an "overspeed" warning if these values are exceeded.Static thrust by itself doesn't say anything about how fast an aircraft will fly; it's only one factor in the whole definition of the aircraft FDE (sizes, drag, etc etc).Now setting afterburner on/off (and therefor using the additional thrust defined in the .air file) is never done automatically by FS.So you either need to do that manually, or have it controlled by a gauge. Or, have this function built in the model itself by e.g. adding XML code in the .mdl. (but only the aircraft designer can do that)Cheers, Rob

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>The aircraft.cfg post only the "dry" thrust values and fuel>consumption.>You can only say if there is an afterburner or not, but how>can you determine the amount of additional thrust and fuel>consumption??>It is automatically colculated in the .air file??? and How can>you tweak it???..........>Thanks for answering!! Yes. See REC 1534,"Turbine Afterburner Thrust Factor vs Mach No" in the AIR file. Generally, the y value increases with Mach, at least past Mach 1.0. Supersonic jets that exceed Mach 1.3 or so should have BOOL 1534 set True, otherwise they will run away' with increasing thrust at higher Mach numbers. Even without the afterburner toggled. TSFC increases by 2.05 when the afterburner is enabled. You will need Aired.exe and my Aired.ini file to get at these settings. Check for aired.ini and a link to Aired. DUMP the aired.ini in the Aired package! Ron

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