Can I erase my disk if my MacBook Air won't start
Can you erase your disk in Disk manager if you can’t get your MacBook Air to start
[Re-Titled by Moderator]
If it's because of a software issue, start up from the recovery system and then use the Disk Utility.
If it's because of a hardware issue, not without using Target Disk mode. If that's not available or you don't have another Mac, no.
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