Hey RT. Yes you can add a beacon but it will take some experimentation to get it positioned on the aircraft where you want it. Below is a Default 747 lights from CFG. (Light.0=is the numer of the effect)(3 second value is the kind of effect)(-150.30 is the X position ahead or behind the sim reference point. Neg.aft Pos. ahead)(-102.56 is the Y axis or lateral position)(3.22 is the Z position or height from Ref. Neg.below Pos.above)(fx_navred is the effect file used.) So what you need is to use the aircraft CFG your trying to add the beacon to and use the other positions to place your beacon. Hope this will help you figure this out. Greg

[LIGHTS]
//Types: 1=beacon, 2=strobe, 3=navigation, 4=cockpit, 5=landing                  
light.0 = 3, -150.30, -102.56,   3.22, fx_navredh ,
light.1 = 3, -150.30,  102.56,   3.22, fx_navgreh ,
light.2 = 3, -223.85,    0.00,   8.85, fx_navwhih ,
light.3 = 2, -150.30, -102.56,   3.22, fx_strobeh ,
light.4 = 2, -150.30,  102.56,   3.22, fx_strobeh ,
light.5 = 2, -228.97,    0.00,  44.62, fx_strobeh ,
light.6 = 1,  -45.05,    0.00,  14.65, fx_beaconh ,
light.7 = 1,  -80.22,    0.00, -12.05, fx_beaconb ,
light.8 = 4,  -16.24,    0.00,   9.19, fx_vclighth,

Hey RT. That is text based and can be changed in the effects file itsself. Try downloading the effects SDK from this site and study it. This will tell you all you need to know about modifying effects files.
http://www.microsoft.com/games/flightsimulator/fs2004_downloads_sdk.asp#panels

Do'nt forget to make a copy of the effects file and change the name so you do'nt change all the effects in FS9 unless thats what you want. Once your done making your new Effect file you'll have to change the Effects file name in the lights portion of the Aircraft CFG.