HS has opted to "stay the course" with MIL-P-55110, MIL-P-50884 and
MIL-S-13949 (for materials) in lieu of the "equivalent" IPC specs due to the
ambiguity and proliferation of "agreed to between buyer and seller" that is
sprinkled throughout new IPC specs.  Our aerospace products are all Class 3,
and many are "flight critical" or "flight essential" and are expected to
perform for decades.  We would have to create a spec (HS) around a spec
(IPC) in order to remove the ambiguities and buyer/seller option clauses.
This would basically defeat the purpose of migrating from the MIL specs to
the equivalent IPC specs.  I firmly believe that IPC needs to take a
stronger position on safeguarding the Class 3 needs, and establish specific
requirements for same, without all the ambiguity and buyer/seller option
clauses.  I does not serve the industry to have a proliferation of company
specs wrapped around industry specs.  That would put us back to the 1960's
and 1970's when we HAD to create internal specifications to cover the myriad
of items not controlled adequately in the MIL specs.

> Richard Grannells
> Hamilton Sundstrand / UTC
> Mfg. Technical Specialist
> 1 Hamilton Road  MS: 3-2-F2
> Windsor Locks, CT  06096-1000
> * Tel: (860) 654-9489
> * eFax: (860) 660-2972 (Note New Number)
> *[mailto:[log in to unmask]]
>


-----Original Message-----
From: Chris Mahanna [mailto:[log in to unmask]]
Sent: Thursday, January 30, 2003 9:12 AM
To: [log in to unmask]
Subject: Re: [IPC-600-6012] Panel Acceptance


The larger issue,

The sole purpose of specifications is to ease trade.  Users can, if they
choose, grab all or part of a specification "off the shelf" and use this
document to manage their risks and consequently yields and prices.  A
serious con of this method of trade is that a relatively small group
(hopefully a competent, open, well defined quorum) determines the level(s)
of risk.  There is NO way around this without undermining the ideals of
specification writing.  IMO there are two key problems drastically effecting
the efficiency of the IPC specifications:

1) ambiguity
2) the proliferation of the phrase "agreed to between buyer and seller"

In the recent emails I have read between the lines:

1) a tendency not to want to admit there is an ambiguity
2) a tendency to think that this forum is a well defined quorum capable of
setting level(s) of risk, by "interpreting" ambiguities.
3) a tendency to say well let's just leave to "agreed to between buyer and
seller"


Don't get me wrong, this forum is an wonderful tool.  I just feel that it
would be more productive to have a structured way to handle these issues:

1) decide if there is an ambiguity
2) debate possible level(s) of risk to be set
3) RECORD these possibilities and
4) take them to the meeting where we can vote
5) invoke the IPC version of openness by sending the chosen verbiage out

Just my two cents,

Chris Mahanna
Quality Manager
Robisan Laboratory Inc.
6502 E. 21st Street
Indianapolis, Indiana 46219
317.353.6249 phone
317.917.2379 fax