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Comment by abfan1127 | Hacker News Reader

my first thought was what happens when it leaks out?

If the internal pressure in the device is lower than one atm, the leakage is easier to contain because it's not helium wanting to go out, but air pushing to come in.

Eventually it will happen and the internal drive atmosphere will be compromised to a point it doesn't work anymore. By then, it should be safe enough to open the drive in a clean Helium-filled room and reseal it.

Or just read the data, store it someplace more durable, and put the drive in a museum.

I'm no physicist, but I don't think diffusion works that way.

Even if the internal pressure is 1% of a standard atmosphere, if the density of helium inside is higher than the density of helium outside, the helium will still "want" to leave the box.

So it becomes read only when helium leaks out?

I though it would just lead to more heat, but reading this[1] from Seagate it seems indeed possible that the drive will not function if too much air gets in:

Furthermore, the use of a higher number of thinner disks is not possible because the windage induces turbulence and makes 7200-RPM tracking impossible at the desired TPIs. The only way to reduce windage in air-filled HDDs is to significantly lower the spindle speed (RPM). However, the largest part of the business-critical market is not willing to accept lower RPMs due to the performance and throughput loss. This means that helium HDD technology is the only viable path forward for delivering higher capacities because it will allow for an increased number of thinner disks.

That said, they also go into the efforts they do to seal the helium, so hopefully the helium stays put...

[1]: https://www.seagate.com/files/www-content/product-content/en...

I'll interpret that as: The drive could be designed with a failsafe lower-RPM mode but it's not worth the engineering budget to allow more than one speed.

Especially looking at WD's "5400 RPM Class" thing as evidence that it takes effort to change the speed of a drive.

I have no idea. May become unreadable if the head can't read because the disk is too far (or if it's too close and it crashes on the disk)

Sounds like planned obsolescence.

It’s not planned obsolescence to include Helium when the medium requires it. If you want 18 TB, you’re going to need Helium (from what I know), but if you want less, you might not get it. Planned obsolescence is about planning (hence the name) to make a device worse to encourage upgrading. The device going bad after a while simply by its nature just makes the obsolescence aspect an added benefit.

Is it planned obsolescence that alkaline batteries go bad if left unused for a while? That moving parts in a car can wear out? I wouldn’t say it is.

This class of drive will typically have a design life of 5yrs at 100% duty.

100% duty cycle on the spindle motors, perhaps. But they're definitely not rated for actively performing IO 100% of the time.

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