Received-SPF: softfail
 receiver=logan.com; client-ip=64.102.122.149; envelope-from=echristley@nc.rr.com
Message-ID: <42A5DDA9.5050909@nc.rr.com>
Date: Tue, 07 Jun 2005 13:47:21 -0400
From: Ernest Christley <echristley@nc.rr.com>
User-Agent: Mozilla Thunderbird 1.0.2 (X11/20050317)
MIME-Version: 1.0
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: rotary risks. MTBE and the gospel ...
References: <list-987422@logan.com>
In-Reply-To: <list-987422@logan.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit

al p wick wrote:

>Let's try this word experiment. Our job is to make clocks. Two types are
>made. The Alwick 2000 all electronic clock and the billybob100 with 100
>mechanical components. Gears, all that traditional stuff. We sell these. 
>At the end of a year, the customers return 1% of the Alwick 2000
>electronic clock. 
>Customers return 50% of the Billybob 100 multi gear clocks. Seems gears 2
>and 17 bind and it stops working. 
>
>Which has the higher failure risk? Well the Billybob 100 of course. The
>return rate is conclusive evidence. 
>
>But what if the return rates were the opposite? Which then would be
>higher risk? It would be the Alwick 2000. 
>
>So the point is, that parts count is not the definition of risk. Yes, in
>many things they coincide. But you don't get to make that assumption. You
>have to compare your theory to the facts.
>
>  
>

But that word experiment is way oversimplified and doesn't model the 
comparison between rotary and piston engines.

Let's make the electronic clock a nuclear powered affair and the watch 
one of the finest Swiss models.  No problems in the first or second 
year, but which would be the first to start showing signs of wear and 
degraded performance?  Which one would need more and more maintenance?  
Which one could be expected to run indefinitely without intervention?  
The simpler one that doesn't have 100 gears wearing out.  There is a 
reason for watches to have super-hard quartz movements.  The mechanical 
complexity multiplies the problems created by out of tolerance parts, 
which is caused in turn by even the smallest amount of wear.

Let's restate the premise so that we're looking at apples vs apples.

Of two systems, designed properly and to the same quality standards, the 
simpler one will be more reliable.

-- 
         ,|"|"|,                                    |
----===<{{(oQo)}}>===----        Dyke Delta         |
        o|  d  |o          www.ernest.isa-geek.org  |