I can't turn on radar binded on " I ".

Hi, I'm pretty new in dcs and I got problem. When I start any mission everything is okey, I can use both radars/scanners (I and O). But when I join to any server the radar binded as 'I' doesn't work. I just can't turn it on - pressing " I " gives nothing. Restarting the game gives nothing too. When I get into mission where I start in the air everything is okey. The same with official tutorial (su-27). I downloaded standalone version of dcs and there is the same problem. Do you have any solution? Am I forgetting about something? I'm flying on simulator mode.

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I must be in the air to use this scanner. Thread to close. :D