Not only annoying! It would make the drive dead in a matter of months probably.
So far I have found out you need to change APM level to allow suspending disks by setting:
hdparm -B 127 /dev/sdX
Where 127 is actually the maximum value allowing suspending drives (spindown).
And then you can change the suspend value with:
hdparm -S 241 /dev/sdX
From the man page:
Values from 241 to 251 specify from 1 to 11 units of 30 minutes, yielding timeouts from 30 minutes to 5.5 hours.
You'll need a service file for this to persist on suspend and reboot. Wait for it.
Something like this should work:
ExecStart=/sbin/hdparm -S 241 -B 127 /dev/sda
Save it as root to:
Then you'll need to activate it with:
systemctl enable hdparm.service
Take this service file only as an example, read thoroughly the
hdparm man page!