A aviation & planes forum. AviationBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » AviationBanter forum » rec.aviation newsgroups » Home Built
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Ack! My ACK!



 
 
Thread Tools Display Modes
  #11  
Old July 11th 03, 02:29 AM
Cy Galley
external usenet poster
 
Posts: n/a
Default

I have a simplistic question. Did the battery replacement "cure" the
problem?


"Robert Bonomi" bonomi@c-ns. wrote in message
...
In article ,
Gerry Caron wrote:

"A@AA" wrote in message
...
Jim, assuming that the ELT does act as he believes it does - that it

alarms when
a secondary battery dies, and that happens shy of it's stated service

life - I'd
think that was bad.


That's one helluvan assumption. Is 3 years in use shy of it's stated
service life? What is the stated service life?


I hate (not! to inject facts into a good argument, but the original
poster _did_ indicate the stated service life. FIVE YEARS. It died
at just short of _four_. *HIS* revised new* 'replacement schedule', based
on the observed evidence, is now three years.

Did it alarm because the
battery died or was there a short in the remote that drained the battery

and
triggered the ELT? If there was a short, was it internal to the battery
(random failure), caused by a cold solder joint (workmanship),
water/moisture intrusion or excessive vibration from a poorly located

mount
(bad installation), or a large current induced into the connecting cable
(secondary effect)?

There are lots of possible failure modes and results. Until you've

analyzed
the failure and determined the root cause, you can draw no conclusions
regarding the design or anything else.
As for being bad, maybe not. What does the System Safety Analysis say?
Which is worse; a latent failure where it doesn't work when you need it

or a
false alarm? At least with the false alarm you are alerted to the fact

it's
not working. You do monitor guard, don't you?

If you can't call it a design flaw, what do you call it? A Bad

Thing(tm)?

Maybe, or possibly a Feature? ;-) It could be that way because it's

the
safest failure mode. Or maybe the company (and their lawyers) wanted it
that way. Much more likely to be sued if it fails to work after a crash
than if it false alarms. Then again, it could be a very unlikely random
failure mode.


That last can be dismissed. The original poster stated "*IF* a dying
battery *ALWAYS* causes a false alarm..." as the qualifying condition for
claiming design flaw. That precludes the possibility of an 'unlikely
random failure mode'.

And don't try to argue that random failures are design flaws. Take a

course
in reliability engineering. If you're bored, read MIL-HDBK-17.

I agree, he should contact the manufacturer before coming to an open

forum
and
posting stuff like this, it may be a completely different situation

than
what
he's describing.


He absolutely should. The holder of a TSOA is legally bound to

investigate
reported failures of their product. (note the key word "reported.") If
they find a design flaw that compromises flight safety, they must report

it
to the FAA within 24 hours. They'll probably argue with the FAA over the
corrective action, but they will report it. If they don't report it,

they
risk having their TSOA pulled and their business shut down. Even minor
issues can result in SILs or SDRs, which exist to improve the product and
safety so it pays to report it.

But it might be *exactly* as he's describing, and I don't
think his lack of an EE degree means he can't reasonably comment that a
product's designed in failure mode is awfuly unwise.


True, it might be exactly as described, but I'm with Jim on this one. I
don't think that even with an EE degree he can reasonably comment on the
design. Only someone who has specific knowledge of the design and can
evaluate all the data surrounding the failure can make a reasonable

comment.

In 26 years in aerospace, I've learned a few things. One of the big ones

is
to not publicly speculate on a failure--you're probably wrong and will

only
make a fool of yourself. Get the data, analyze it, verify cause and

effect,
and only then make your statement.

Gerry






  #12  
Old July 11th 03, 03:25 PM
Ron Natalie
external usenet poster
 
Posts: n/a
Default


"Del Rawlins" wrote in message ...
On 10 Jul 2003 04:32 PM, Gerry Caron posted the following:

Aviation is a small community. Avionics is only a small part of that.
Everybody knows everybody or someone who does. This isn't an industry
where companies can afford to alienate customers.


JPI still seems to be in business.

And NARCO...


  #13  
Old July 15th 03, 07:48 AM
MikeremlaP
external usenet poster
 
Posts: n/a
Default

I have a simplistic question. Did the battery replacement "cure" the
problem?


Yes.

I also tried installing the old "not quite dead yet" battery in again. 3 times
installed, 3 times set the ELT off.

I planned to take a variable power supply and work the voltage down slowly from
6 volts to zero, but can't find my power supply.

Also, faxed ACK on Thursday. As of today, nothing heard... but maybe they were
busy with Arlington.

HTH,

Mike Palmer
Excellence in Ergonomics
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT +1. The time now is 06:43 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 AviationBanter.
The comments are property of their posters.