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<p>It may be that several FAR regs are interlinked. FAR 25.143(g)
seems to be a general controllability requirement relating to the
(pilot+plane) combination. The stall characteristics reg
§25.203(a) is a specific case where controllability is important,
etc.</p>
<p>The MAX might have transgressed more than one, so trying to pin
it down to a single reg might not be helpful.</p>
<p>The main thing is that all these regs are there to maximise plane
safety.</p>
<p>And the focus of this discussion should be HOW those regs are
met. Personally I prefer plane physics.</p>
<p>Peter<br>
</p>
<div class="moz-cite-prefix">On 01/12/2020 22:29, Dewi Daniels
wrote:<br>
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cite="mid:CANQd8eUjTmQNPS=JdL4p4-OeM_VWyojiRM_eDcE8N3oBKL26RA@mail.gmail.com">
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<div dir="ltr">My understanding is that MCAS was introduced to
comply with FAR 25.143(g), which states:</div>
<div dir="ltr"><br>
When maneuvering at a constant airspeed or Mach number (up to
VFC/MFC), the stick forces and the gradient of the stick force
versus maneuvering load factor must lie within satisfactory
limits. The stick forces must not be so great as to make
excessive demands on the pilot’s strength when maneuvering the
airplane, and must not be so low that the airplane can easily
be overstressed inadvertently. Changes of gradient that occur
with changes of load factor must not cause undue difficulty in
maintaining control of the airplane, and local gradients must
not be so low as to result in a danger of overcontrolling.<br>
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<p><a
name="SignatureSanitizer_SafeHtmlFilter_UNIQUE_ID_SafeHtmlFilter__MailAutoSig"
moz-do-not-send="true"><span
style="font-size:10pt;font-family:Arial,sans-serif">Yours,</span></a></p>
<p><span
style="font-family:Arial,sans-serif;font-size:10pt">Dewi
Daniels | Director | Software Safety Limited</span><br>
</p>
<p><span
style="font-size:10pt;font-family:Arial,sans-serif"
lang="FR">Telephone +44 7968 837742 | Email </span><span
style="font-size:10pt;font-family:Arial,sans-serif;color:purple"
lang="FR"><a href="mailto:ddaniels@verocel.com"
target="_blank" moz-do-not-send="true">d</a><a
href="mailto:ewi.daniels@software-safety.com"
target="_blank" moz-do-not-send="true">ewi.daniels@software-safety.com</a></span></p>
<p><font face="Arial, sans-serif">Software Safety
Limited is a company registered in England and
Wales. Company number: </font><font face="Arial,
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sans-serif">. Registered office: Fairfield, 30F
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style="font-size:small;font-family:Arial,sans-serif">,
United Kingdom </span><span
style="font-size:small;font-family:Arial,sans-serif">BA14
6AZ</span></p>
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