Hi All, I was Flying the Cargolux 747-400F on Vatsim OMSJ - ELLX There was quite a bit of traffic over Iran and i was keeping an eye on a BAW 747 flying in the opposite direction bound for Dubai. This aircraft passed me incredibly close, directly overhead but i did not recieve any tcas traffic alerts ( I was in controlled airspace tcas set up correctly) I could see him on my nav display but no alert? This is the closest i have had to a mid air collision in all my years of using FS. When i used to fly offline i would get alerts for aircraft that were not really a major threat. So do alerts work the same online? Rob Prest BTW i ran the TCAS test before departure

The question is how close? If you are at different altitudes and both in level flight there should be no conflict and TCAS won't alert you. Unless you are at nearly the same altitude.

Hi, I Understand that if one of us is climbing or in des i would hear "adjust vertical speed" etc. The reason i ask is during cruise when offline i would here "Traffic Traffic" I look out the window and a AI aircraft is cruising a fair distance away. This guy online shot right over my head, i run fs on a 32" LCD with trackIR and got the shock of my life seeing this 747-400 comming at me. thank god for servinfo. Rob Prest

Hi Rob,one of the reasons 2 or 3 pilots sitting in the cockpit - also to watch the ND where all the infos about other aircraft are shown . . . one of our RL pilots in my company mentionned once,TCAS is the best invention in the airline history since ages !You will see the conflicting traffic well in advance - unless you set the radius to 5 NM ... - you have all info about altitude of conflicting traffic, either difference to your alt or straight alt information. In RL you would call ATC and req clarification. 1000ft difference in alt look awful close when 2 ac are at M.85 . . .Karl-Heinz - EDDI/THF " Tempelhof "" The mother of all airports " - Sir Norman Foster

Alerts work the same online as offline.If you both were in straight level flight, there is no reason for TCAS to alert you. I've certainly passed planes at 1000ft separation and never had a TCAS alert (as I would expect).Do you happen to recall the altitute difference displayed in TCAS? If you were in controlled airspace, I'm sure the controller had you guys at least 1000ft apart. Yeah, it can be disconcerting at first, because 1000ft isn't really that much... but if it's good enough for the FAA, it's good enough for me!- Bill