X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail.theofficenet.com ([65.166.240.5] verified) by logan.com (CommuniGate Pro SMTP 4.3.4) with SMTP id 984500 for flyrotary@lancaironline.net; Sat, 04 Jun 2005 11:39:40 -0400 Received-SPF: none receiver=logan.com; client-ip=65.166.240.5; envelope-from=jackoford@theofficenet.com Received: (qmail 19925 invoked from network); 4 Jun 2005 15:36:11 -0000 Received: from dpc691941229.direcpc.com (HELO jack) (69.19.41.229) by mail.theofficenet.com with SMTP; 4 Jun 2005 15:36:11 -0000 Message-ID: <001d01c5691b$4c5353d0$6601a8c0@jack> From: "Jack Ford" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Apples and Oranges (was: COZY: Rotary risks) Date: Sat, 4 Jun 2005 08:37:13 -0700 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_001A_01C568E0.9B38C880" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1478 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1478 This is a multi-part message in MIME format. ------=_NextPart_000_001A_01C568E0.9B38C880 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable We now have a tool to prioritize risk. Maybe not a perfect tool, but the = only one I ever heard of that is used very successfully in industry.=20 The only exact sciences are Physics, Chemistry and Mathematics. All = other sciences use components of these disciplines to predict the = outcomes of their ART. Engineering and Medicine are not sciences, they = are ARTS. Good engineers and researchers know this instinctively. That's one = reason experience is so valuable: It develops the artist. Back to the point. If the method is not particularly sophisticated, that = doesn't make it invalid. The point is that all things are relative, and = this is a method to align, order and relate priorities. I have not seen = any other. I'll use it in my project (Cozy MKIV), hopefully in consultation with Al = Wick. 2c Jack Ford ----- Original Message -----=20 From: David Leonard=20 To: Rotary motors in aircraft=20 Sent: Friday, June 03, 2005 9:42 PM Subject: Message with possible fraud attempt: [FlyRotary] Re: Apples = and Oranges (was: COZY: Rotary risks) = -------------------------------------------------------------------------= -------------------------- Panda Titanium Antivirus 2005 has detected that this email could be = spoofed Take maximum precautions, as spoofed emails could be the sign of a = fraud attempt. = -------------------------------------------------------------------------= -------------------------- On 6/3/05, Bill Dube wrote:=20 >http://www.maddyhome.com/canardpages/pages/alwick/risk.html=20 This is an interesting read, but a flawed analysis. It looks like a mathematician's approach, rather than an engineer's approach. He compares failure rates for auto engine components = operating in=20 an automobile with aircraft components operating in an aircraft. He = then assumes that the auto component will have the same mean time between failures when installed on an airplane. The speed and load profile for a car component and an = airplane=20 component are completely different. This would explain how he "doesn't get it" about the = inherent MTBF advantages of a rotary engine. It is quite likely that he doesn't understand the drastic effect fatigue failure has on the MTBF as you = increase the continuous load. As a rule of thumb, if you double the reversing load, you = decrease the the cycle life by a factor of 100. For a car engine connecting = rod in an airplane, you are not only (at least) doubling the load (torque) = you are=20 also doubling the RPM, so the connecting rod will have a MTBF 200 = times shorter in the airplane than in the car. The rotary has very few moving parts subject to fatigue = failure (unlike piston engines.)=20 Bill Dube' Bill, I agree. This method is neither scientific, professional, = objective or even sophisticated. First year medical students would do a = better job of seeing fallacy (in the research sense) and applying = statistical methods.=20 Al is right that it is important to examine these issues and his = system can help clarify which issues are more important. But I sure = wouldn't pay $150 to go to any seminars. The point system he uses has = no reference validation, no statistical power analysis, and therefore = very little meaning.=20 While he is right about the CAS being an issue, he seems very = uninformed on other issues yet comes across as someone who feels that he = is well informed. He even went so far as to presume to know the way = Tracy thinks and approaches problems.=20 Anyway, don't put too much faith in his professional "risk analysis." = He may very well have a great deal to share, but his system is as = armature as my rotary installation. --=20 Dave Leonard Turbo Rotary RV-6 N4VY=20 http://members.aol.com/_ht_a/rotaryroster/index.html http://members.aol.com/vp4skydoc/index.html=20 = -------------------------------------------------------------------------= -------------------------- Panda Titanium Antivirus 2005 has detected that this email could be = spoofed Take maximum precautions, as spoofed emails could be the sign of a = fraud attempt. = -------------------------------------------------------------------------= -------------------------- ------=_NextPart_000_001A_01C568E0.9B38C880 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
We now have a tool to prioritize risk. = Maybe not a=20 perfect tool, but the only one I ever heard of that is used=20 very successfully in industry. 
 
The only exact sciences are Physics, = Chemistry and=20 Mathematics. All other sciences use components of these disciplines to = predict=20 the outcomes of their ART. Engineering and Medicine are not sciences, = they are=20 ARTS.
 
Good engineers and researchers know = this=20 instinctively. That's one reason experience is so valuable: It develops = the=20 artist.
 
Back to the point. If the method is not = particularly sophisticated, that doesn't make it invalid. The point is = that all=20 things are relative, and this is a method to align, order and relate = priorities.=20 I have not seen any other.
 
I'll use it in my project (Cozy MKIV), = hopefully in=20 consultation with Al Wick.
 
2c
 
Jack Ford
 
----- Original Message -----
From:=20 David=20 Leonard
Sent: Friday, June 03, 2005 = 9:42 PM
Subject: Message with possible = fraud=20 attempt: [FlyRotary] Re: Apples and Oranges (was: COZY: Rotary = risks)
=



--------------------------------------------------= -------------------------------------------------
Panda=20 Titanium Antivirus 2005 has detected that this email could be=20 spoofed

Take maximum precautions, as spoofed emails could = be the=20 sign of a fraud=20 = attempt.
-------------------------------------------------------------= --------------------------------------


On 6/3/05, Bill=20 Dube <bdube@al.noaa.gov>=20 wrote:=20

>http= ://www.maddyhome.com/canardpages/pages/alwick/risk.html=20

        This is = an=20 interesting read, but a flawed=20 analysis.

        It = looks=20 like a mathematician's approach, rather than an
engineer's=20 approach.

        He = compares=20 failure rates for auto engine components operating in
an = automobile with=20 aircraft components operating in an aircraft. He then
assumes = that the=20 auto component will have the same mean time between
failures when = installed on an=20 airplane.

        The = speed=20 and load profile for a car component and an airplane
component = are=20 completely=20 = different.

        This = would=20 explain how he "doesn't get it" about the inherent = MTBF
advantages of a=20 rotary engine. It is quite likely that he doesn't
understand the = drastic=20 effect fatigue failure has on the MTBF as you
increase the = continuous=20 load.

        As a = rule of=20 thumb, if you double the reversing load, you decrease
the the = cycle life=20 by a factor of 100. For a car engine connecting rod in
an = airplane, you=20 are not only (at least) doubling the load (torque) you are
also = doubling=20 the RPM, so the connecting rod will have a MTBF 200 times
shorter = in the=20 airplane than in the=20 car.

        The = rotary has=20 very few moving parts subject to fatigue failure
(unlike piston = engines.)=20

        Bill=20 Dube'
 
Bill, I agree.  This method is neither scientific, = professional,=20 objective or even sophisticated.  First year medical students = would do a=20 better job of seeing fallacy (in the research sense) and applying = statistical=20 methods.
 
Al is right that it is important to examine these issues and his = system=20 can help clarify which issues are more important.  But I sure = wouldn't=20 pay $150 to go to any seminars.  The point system he uses has no=20 reference validation, no statistical power analysis, and therefore = very little=20 meaning.
 
While he is right about the CAS being an issue, he seems very = uninformed=20 on other issues yet comes across as someone who feels that he is well=20 informed.  He even went so far as to presume to know the way = Tracy thinks=20 and approaches problems.
 
Anyway, don't put too much faith in his professional "risk=20 analysis."  He may very well have a great deal to share, but his = system=20 is as armature as my rotary installation.

--
Dave = Leonard
Turbo=20 Rotary RV-6 N4VY
http://memb= ers.aol.com/_ht_a/rotaryroster/index.html
http://members.aol.c= om/vp4skydoc/index.html=20 =


-------------------------------------------------= --------------------------------------------------
Panda=20 Titanium Antivirus 2005 has detected that this email could be=20 spoofed

Take maximum precautions, as spoofed emails could = be the=20 sign of a fraud=20 = attempt.
-------------------------------------------------------------= --------------------------------------
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