|
|
Egads gents, SD makes a 4Gb data card the size of a postage stamp.
The computer interface treats it as a pseudo disk. Vista Nav (or
anyone else) ought to be able to load such a device with program and data and
allow for the shut down of the hard drive. 4 Gb ought to be
enough memory and altitude would not be a factor. Are there no creative
programmers left?
Grayhawk
In a message dated 7/19/2006 3:13:07 P.M. Central Standard Time,
c177av8r@pacbell.net writes:
What I did for a U2 installation (not practical here) was build a
pressure vessel to house the hard disk only. Flew it above 68K
several times successfully.
Still have the hardware even though I haven't used it in 16-18
years. I built it in 1988 according to my autocad drawings.
duane
"Hamid A. Wasti" <hwasti@starband.net>
wrote:
Marvin
Kaye wrote:
> Posted for "Tom Gourley"
:
>
> The Inertial
> Navigation
Unit, one of the two boxes that makes up a complete system,
>
has
> reasonable specs; up to 24,000 feet and operating temperature
from 32F to
> 105F.
I would hardly call that reasonable. And 32F is
the "standard
atmosphere" at about 7,500 feet. 105F is essentially 40C.
It is way
too low for real life use. Temperatures in excess of 80C
behind the
panel are well documented. On a "normal" warm day of 35C, you
can see
temperatures well in excess to 45C in locations where you would
normally
install a box. Places like Phoenix routinely get over 45C in
the shade
during the summer. Just to put things in perspective, a box
with those
temperature specifications would not even get past the front
door to
talk to an automotive company, let alone any aviation company.
> Does this mean the tablet, or Mobile Computing
> Platform
as it's called, will stop working above 10,000 feet. I doubt it.
Wrong
answer. Hard drives count on an air cushion to keep them from
touching
the spinning disk. The damping of the air resistance against
lateral
movement of the head is also taken into consideration when
designing the
closed loop control for positioning the head. As you get
high, the air
thins and both the cushion as well as the damping
decrease The result is
failure to seek if you are lucky, a hard crash
if you are unlucky. This
is not just theory, but is well documented.
Also, the denser the drive,
the more susceptible it is to altitude
related problems.
The
second issue is cooling. Cooling of the CPU. Colling of the power
supplies. Cooling of the graphics chip. Cooling of the
backlight.
Of course, you can ignore all of that and boldly press on
-- many do.
Maybe you will get lucky and things will work for you, maybe
not.
Regards,
Hamid
|
|