<div dir="ltr"><div dir="ltr"><div class="gmail_default" style="font-family:georgia,serif;font-size:large">No rejoinder from Kevin (or any message whatsoever) has shown up in my e-mail from the list, at either my work or personal addresses. Perhaps it wasn't sent to the full list. Perhaps it somehow was blocked by two very different spam filters, but of all the people on the list Kevin is among the least likely to write something that could possibly be flagged as spam. Whatever happened, I haven't seen it.</div><div class="gmail_default" style="font-family:georgia,serif;font-size:large"><br></div><div class="gmail_default" style="font-family:georgia,serif;font-size:large">I'm with Tom on appreciating the technical exchanges and not appreciating the pointed jibes. I'm not a fan of dripping sarcasm either, but do quite enjoy clever sarcasm. </div><div><div dir="ltr" data-smartmail="gmail_signature"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><b><font color="#ff7003" face="trebuchet ms, sans-serif" size="4"><br></font></b></div><div dir="ltr"><font size="4"><b><font color="#000000" style="font-family:"trebuchet ms",sans-serif">--</font><br><i><font face="georgia, serif"><font color="#cc0000">c</font><font color="#073763">Mh</font></font></i></b></font></div><div dir="ltr"><div dir="ltr"><br></div><div><div><br></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Nov 24, 2020 at 6:23 PM Tom Ferrell <<a href="mailto:tom@faaconsulting.com" target="_blank">tom@faaconsulting.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Glad you are amused, Peter. I have been on this list a long time, and I really appreciate the technical exchanges, the dripping sarcasm and pointed jibes less so. The safest thing to do with the max is to permanently ground this variant and not attempt to overcome the inherent aerodynamic instability in a certain flight regime. It's an interesting take given how many other aircraft, admittedly mostly on the military side, where inherent instability is routinely overcome by sophisticated flight controls. It is also an incredibly costly position to hold given the impacts to the airlines, to Boeing, and most of all to the flying public given the sharp reduction in overall capacity that the grounding has caused, something only masked by the pandemic. It is so easy to condemn design decisions in hindsight. I never defended Boeing's actions nor the design. Clearly their safety culture has eroded. This started the minute they decided to let the finance folks drive the company agenda<br>
rather than maintain the engineering centric leadership that made them a world leader. They should never have moved their HQ to Chicago away from the heart of their business IMHO.<br>
<br>
My original statement was in regards to the level of rigor employed in the recertification. I know quite a few of the involved in crawling through the design, first of MCAS and then much more broadly. They are sharp, they are conscientious, and they recognize the gravity of the situation. You have to separate the front line engineers from the management team. As for Kevin's post, I was involved in looking for the byzantine type faults he mentions in the AIMS system. I raised this issue in another level A system on a later aircraft when there appeared to be a clear possibility of this type of fault, and it was addressed by the supplier. It's unclear why you consider this not to be something that is looked for with some frequency. I stand by my original statements even with Kevin's articulate rejoinder.<br>
<br>
-----Original Message-----<br>
From: systemsafety <<a href="mailto:systemsafety-bounces@lists.techfak.uni-bielefeld.de" target="_blank">systemsafety-bounces@lists.techfak.uni-bielefeld.de</a>> On Behalf Of Peter Bernard Ladkin<br>
Sent: Tuesday, November 24, 2020 12:25 PM<br>
To: <a href="mailto:systemsafety@lists.techfak.uni-bielefeld.de" target="_blank">systemsafety@lists.techfak.uni-bielefeld.de</a><br>
Subject: Re: [SystemSafety] [External] Re: "FAA chief '100% confident' of 737 MAX safety as flights to resume"<br>
<br>
This list exists to further the science and engineering of safety. There is not always a lot of traffic, but every so often there are decisive interventions.<br>
<br>
I'd like to say that Tom Ferrell's justification of the MAX recertification, and Kevin Driscoll's rejoinder, are to my mind classics of the art.<br>
<br>
This is why this list exists. Thanks to both.<br>
<br>
PBL<br>
<br>
Prof. Peter Bernard Ladkin, Bielefeld, Germany ClaireTheWhiteRabbit RIP<br>
Tel+msg +49 (0)521 880 7319 <a href="http://www.rvs-bi.de" rel="noreferrer" target="_blank">www.rvs-bi.de</a><br>
<br>
<br>
<br>
<br>
<br>
_______________________________________________<br>
The System Safety Mailing List<br>
<a href="mailto:systemsafety@TechFak.Uni-Bielefeld.DE" target="_blank">systemsafety@TechFak.Uni-Bielefeld.DE</a><br>
Manage your subscription: <a href="https://lists.techfak.uni-bielefeld.de/mailman/listinfo/systemsafety" rel="noreferrer" target="_blank">https://lists.techfak.uni-bielefeld.de/mailman/listinfo/systemsafety</a><br>
</blockquote></div></div>