Yeah, airplane mode will leave the phone on but disconnect you from all networks, so you can't get calls/texts, so it's functionally the same as if they were silenced.
You could maybe also change your ringtone and text alert sound independently of the alarm sound, and just set them to something very quiet or even just a silent .wav file.
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SuperNiceDog didn't have to reconcile his name...
But Dauntless Hunter is now MrGreenonion