Path: utzoo!attcan!uunet!cs.utexas.edu!usc!zaphod.mps.ohio-state.edu!rpi!crdgw1!crdos1!davidsen
From: davidsen@crdos1.crd.ge.COM (Wm E Davidsen Jr)
Newsgroups: comp.arch
Subject: Re: Data Storage density questions
Message-ID: <2378@crdos1.crd.ge.COM>
Date: 2 Aug 90 13:20:53 GMT
References: <2635@mindlink.UUCP> <10048@pt.cs.cmu.edu> <AGLEW.90Jul30145243@oberon.crhc.uiuc.edu> <2684@network.ucsd.edu>
Reply-To: davidsen@crdos1.crd.ge.com (bill davidsen)
Organization: GE Corp R&D Center, Schenectady NY
Lines: 20

In article <2684@network.ucsd.edu> mbk@inls1.ucsd.edu (Matt Kennel) writes:

| You mean disk drives are not evacuated?
| Wow, you learn something new every day.  
| 
| Come to think of it, why not?  I should think that it would be nice to 
| be able to position the head without worrying about such ugly things as the
| viscocity of air and its pressure & temperature and the roughness of the
| platter.  Fluid mechanics is exceedingly tough so why bother when you
| don't have to?

  The whole technology of hard disks depends on air. That's what keeps
the heads from hitting the platters. Without air you would have to have
some super accurate means of positioning the heads near the platter. I
don't currently see any replacement technology ready to come online.

  Even the Bernouli based drives use air, but in a slightly diferent way.
-- 
bill davidsen	(davidsen@crdos1.crd.GE.COM -or- uunet!crdgw1!crdos1!davidsen)
            "Stupidity, like virtue, is its own reward" -me