I have an F-14 in my hangar that has a cool effect and sound when you go to Mach.  You can see the boom develop and then hear it.  I was wondering how I'd be able to add this to my AF F-18 I just purchased, or if I could.  Thanks

I think it's an effect/gauge rather than a modelling issue.

Which F-14 model are you talking about?

Okay, I've poked around in the files a little and I've found an "XML" gauge file that seems to be what controls the effect.  All this is alien to me though, so I don't know what to do from here.  On install of the F-14 this gauge along w/ some others are installed into the main "Gauge" folder in FS9.  How do I go about incorporating this in the other planes capable of Mach speed?  Is it something in the aircraft.cfg file?

He's talking about the F-14B by Dino Cattaneo (Catanneo?) Yes indeed it has a pretty neat effect.  Hmm... to do this... I figured out how to do the sound which appears when crossing the sound barrier. Go to the panel.cfg of the F-14A and copy the line (which is located under the gauges section):

gauge40=flightsimstudios!Tomcat_TransSonic, 0,0                 // This Controls the Trans-sonic Boom Effect

Then paste it in the panel.cfg of the F/A-18, after all the previous gauges. It should look like this:

//--Forward-Single-Panel--//------------------------------

[Window00]
file=panel_main.BMP
size_mm=1024
position=1
visible=1
ident=0
window_size= 1.000, 1.000
window_pos= 0.000, 0.000

gauge00=EXTRA-300.WISKEY-COMPASS,  937,559,91,95
gauge01=SimIcons!GPS Icon,  468,800,20,20
gauge02=SimIcons!ATC Icon,  542,800,20,20
gauge03=SimIcons!Map Icon,  517,800,20,20
gauge04=SimIcons!Kneeboard Icon,  493,800,20,20
gauge05=aerial_gau!Throttle_Panel_Icon,  443,800,20,20
gauge06=aerial_gau!Switch_Panel_Icon,  566,800,20,20
gauge07=aerial_gau!PFD,  112,591,201,192
gauge08=aerial_gau!HSI,  705,588,199,190
gauge09=aerial_gau!Avionics,  724,786,21,21
gauge10=aerial_gau!NAV-GPS,  867,786,21,21
gauge11=aerial_gau!Attitude_Display_Switch,  322,737,22,22
gauge12=aerial_gau!HSI_Display_Switch,  677,737,20,20
gauge13=aerial_gau!HUD_Switch,  424,749,32,32
gauge14=aerial_gau!HudPowerSwitch,  600,697,32,30
gauge15=aerial_gau!Autopilot_Master,  398,696,32,30
gauge16=aerial_gau!EMCon,  639,531,20,22
gauge17=aerial_gau!AP_IAS-Mach_Switch,  567,696,32,30
gauge18=aerial_gau!AP_Localizer_Switch,  466,696,32,30
gauge19=aerial_gau!AP_Speed_Switch,  533,696,32,30
gauge20=aerial_gau!AP_IFF_Switch,  432,696,32,30
gauge21=aerial_gau!AP_Approach_Switch,  499,  696 ,32,30
gauge22=aerial_gau!Digi_Clock,  401,466,111,45
gauge23=aerial_gau!Indicator_R,  680,456,177,141
gauge24=aerial_gau!Indicator_L,  169,458,178,141
gauge25=aerial_gau!AOA_Indicator,  328,281,34,83
gauge26=aerial_gau!ADI_Solid,  162,606,102,110
gauge27=aerial_gau!Autopilot,  516,468,112,200
gauge28=af_effects!AF_Flame,  0,0,20,20
gauge29=af_effects!AF_Burn,  0,0,20,20
gauge30=af_effects!AF_Flap_Condense,  0,0,20,20
gauge31=af_effects!AF_Wing_Condense,  0,0,20,20
gauge32=flightsimstudios!Tomcat_TransSonic, 0,0                 // This Controls the Trans-sonic Boom Effect

Now go into the game and it should work. I tried it on my aerialfoundry CF-118 and it worked. You dont get nice visual effect though, just the sound... But its something