Paul: Check before posting. Released today. New technology with
daylight screen.
Lloyd
-----Original Message-----
From: Rotary Engine [
mailto:rotaryeng@earthlink.net]
Sent: Saturday, March 14, 2009 11:07 PM
To: AAA Put this in the To box
Subject: Hard disk at altitude
Just to be clear, I wasn't making an endorsement, I was just passing
on
the info FYI so to speak. I have used tablet computers with
conventional
hard drives up to 17,000 ft with no problems. Your results may vary.
C. Smith
That is interesting. Perhaps they have the problem solved.
What brand? As I understand it the read write head "flies" over the
surface
of the disk in ground effect. The theory is the air density needs to
be
reasonable for this to happen. An airplane speeds up and or increases
the
angle
of attack to fly at higher altitudes to make up for the lower air
density.
--------------------------------------------------------
Here is a web site on the subject and a recent patent.
http://www.pcguide.com/ref/hdd/op/heads/op_Height.htm
Lots of people want to use notebooks with moving map software
as it is 1/10 the cost of aviation moving map software.
I wrote my own years ago and I used a floppy disk to store
the FAA airport data base. :)
The Home Built Glass Cockpit by Paul Lamar
Kitplanes
June 1988 page 69
The future can be here now: electronic
instrument displays in your homebuilt.
Glass Cockpit: Part II by Paul Lamar
Kitplanes
January 1989 page 66
Automatic position reporting could be helpful
when pilot's hands and mind are full.
Paul Lamar
Is it possible that the drive continues to work, but is wearing faster
at higher altitude?
I was thinking maybe the head bumps occasionally and the drive just
rereads that sector
and as you get higher it bumps more.
What kind of bearings do the spindle's use? Air bearings?
I saw something while googling where a guy said his drives fail in
about a year at high altitude.
It may be that he's doing graphics work and have nothing to do with
the altitude.
Wikipedia says that a Google study found that drives have a higher
failure rate at lower temperatures.
I think the bottom line is that it's mechanical and maybe it's easier
to just go solid state.
-Jeff
Paul: Check before posting. Released today. New technology with
daylight screen.
http://www.computerworld.com/action/article.do?command=viewArticleBasic&articleId=9129659&source=NLT_AM
Lloyd
With the Eee PC I can read it with my sun glasses on in everything except
the sun shining directly on it. Rather impressive for a cheap computer.
Paul Lamar
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