X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Thu, 11 Aug 2011 07:42:33 -0400 Message-ID: X-Original-Return-Path: Received: from wolverine.webiness.com ([65.61.103.66] verified) by logan.com (CommuniGate Pro SMTP 5.4.1) with ESMTPS id 5088248 for lml@lancaironline.net; Wed, 10 Aug 2011 13:47:28 -0400 Received-SPF: none receiver=logan.com; client-ip=65.61.103.66; envelope-from=brent@regandesigns.com DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=default; d=regandesigns.com; h=Received:Message-ID:Date:From:User-Agent:X-Accept-Language:MIME-Version:To:Subject:Content-Type; b=O30EKB4nsr0nltlYJYc2xp8Z/WdqA096wIIiy60Ncbw2/2L8VtEjd+2bCmjixzc05VEdk7V/fU0OUSVSCWGqoXQrjtGQMAwVayQA/wEqKhD/b6PY01qqntYepJlhOxJN; Received: from 207-170-226-178.static.twtelecom.net ([207.170.226.178] helo=[192.168.1.101]) by wolverine.webiness.com with esmtpa (Exim 4.69) (envelope-from ) id 1QrCr4-0004PK-Dj for lml@lancaironline.net; Wed, 10 Aug 2011 10:46:10 -0700 X-Original-Message-ID: <4E42C40C.2030200@regandesigns.com> X-Original-Date: Wed, 10 Aug 2011 10:46:52 -0700 From: Brent Regan User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.2) Gecko/20040804 Netscape/7.2 (ax) X-Accept-Language: en-us, en MIME-Version: 1.0 X-Original-To: Lancair Mailing List Subject: Re: Re: TSOs and equipment failure Content-Type: multipart/alternative; boundary="------------040004040608040006000302" X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - wolverine.webiness.com X-AntiAbuse: Original Domain - lancaironline.net X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - regandesigns.com This is a multi-part message in MIME format. --------------040004040608040006000302 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Confusion on TSO's seems rampant. It reminds me of the confusion over "mass" and "weight". TSOs are the Technical Standards that a device must meet to be considered to be said device by the FAA. TSO compliance has little to do with reliability. DO160 is a collection of tests that can be performed on a device to demonstrate that it is robust. Being able to pass these tests is an indicator of how reliable a device will be once installed. DO178 controls the testing and certification of software. Certification is a process by which you demonstrate to the FAA that a given device complies with the applicable TSO and/or will pass the applicable DO160 tests and/or will satisfy the applicable DO178 level standards. Reliability is a generic qualitative term that implies a device will perform as expected when subjected to anticipated conditions. Can you rely on a device to perform as expected. Robustness or ruggedness is a device's ability to perform after being subjected to conditions beyond what is normally anticipated. A device can comply with a TSO and not be TSOed. A device can pass DO160 testing and not be "Certified". Regards Brent Regan --------------040004040608040006000302 Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit Confusion on TSO's seems rampant. It reminds me of the confusion over "mass" and "weight".

TSOs are the Technical Standards that a device must meet to be considered to be said device by the FAA. TSO compliance has little to do with reliability.

DO160 is a collection of tests that can be performed on a device to demonstrate that it is robust. Being able to pass these tests is an indicator of how reliable a device will be once installed.

DO178 controls the testing and certification of software.

Certification is a process by which you demonstrate to the FAA that a given device complies with the applicable TSO and/or will pass the applicable DO160 tests and/or will satisfy the applicable DO178 level standards.

Reliability is a generic qualitative term that implies a device will perform as expected when subjected to anticipated conditions. Can you rely on a device to perform as expected.

Robustness or ruggedness is a device's ability to perform after being subjected to conditions beyond what is normally anticipated.

A device can comply with a TSO and not be TSOed. A device can pass DO160 testing and not be "Certified".

Regards
Brent Regan

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