Good point, John; but does that mean I'm not to blame if I hit the
Bonanza
head on in my experimental or ultralight with the same non-tso'd
altimeter?
dan
On Mar 10, 2009, at 1:44 PM, John Cooper wrote:
I have remained mute on this subject up till now because I really
don't know
what the answer is. And I hate to admit that...
However, here's my opinion....
The altimeter is a required instrument, per FAR 91.205. Therefore,
it must
meet some minimum criteria. For example, you could not install a Timex
watch with an altimeter function, even though it read out in feet.
Neither
could you install one you got from Sharper Image for your car, even
if it
cost more than the TSO version.
The Erco drawing calls for an Aeromarine 520N altimeter. So, for
sure, that
is a suitable instrument. Obviously, it was not TSO'd as the
concept didn't
exist then. So, what constitutes a suitable replacement? Or, put
another
way, is the Chin Wah altimeter from Aircraft Goose for $200 a suitable
replacement? The answer is "it's up to the installer", I think.
Ultimately, the A&P who signs off the install, or, absent that, the
IA who
signs off the next annual, (or the last annual if you as the owner
sneak the
thing in between annuals) will be held responsible for it. Now,
lets assume
you are involved in a mid air collision with an oncoming IFR
Bonanza at 6000
feet. The wreckage of you plane reveals a Chin Wah altimeter stuck
at 5500.
Who's to blame?
Bottom line, If I'm installing that altimeter, I want some
assurance it is
an aircraft quality part. The TSO is that insurance. Your IA may
view it
differently, assuming he knows what he's looking at...
John Cooper
Skyport Services
www.skyportservices.net
