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Wow. The emotional responses! Take a look at my statement: "It only has
three moving parts, therefore it's safer". I can't believe all the stuff
you guys are reading into it!
Let me explain. If your goal is to determine if one thing is safer than
another...guess what? Counting the number of pieces is NOT the definition
of safety. You have to look at the whole picture. You don't focus on one
feature.
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.
-al
On Mon, 6 Jun 2005 20:48:09 -0400 WALTER B KERR <jbker@juno.com> writes:
> Al W wrote:>
>
> > Here's an excellent example. I've seen people describe their
> > reasoning
> > for going rotary. Often I would hear: "It only has three moving
> > parts,
> > therefore it's safer". I suspect that 80% of you believed that.
> That
> > is a
> > gross error in perspective. No maybe, it's a huge distortion. It's
>
> > a
> > wonderful theory, it has a component of truth in it, but totally
> > fails
> > the tests for significance. If a logical theory is not
> significant,
> > you
> > dump the theory.
> --------------------------------------------------------
>
> Have stayed out of this as long as I can, but it seems strange to me
> as a
> gas turbine designer of 33 years that Al would make this comment
> without
> at least backing his words up a bit. I find it hard to believe that
> a
> modern technology reciprocating engine that is snapping pistons back
> and
> forth at 5000 rpm with cams and valves is anywhere as safe as a
> rotary.
> If the modern tech recip requires a PSRU and the addition of water
> cooling those things components are canceling.
> Having participated in many FEMA studies over the years ,I find some
> of
> Al's comments a bit strange. His heart may be in the right place to
> try
> to help us Rotorheads, but am not convinced he is helping us sort
> out
> what is important to take care of to eliminate failures.
>
> Will never forget my intro to rotary's. A friend at work raced a
> rotary
> powered car. He took the car to the Daytona 24 hour without detuning
> and
> after returning he left the car on the trailer and went to miami
> next
> week without any additional work. This was a totally different story
> from
> the recip guys. They installed very expensive forged lightweight
> parts
> and deturned the engine. After the race they replaced all of them
> before
> the next event. Does that say something to you about the robustness
> of
> the rotary? Does to me and is one of the big reasons I am flying
> one
> today.
>
> Bernie Kerr, 40 hours on 13B powered RV9A,
>
> PS. Do I feel as comfortable with the 9A as I did when I sold the
> Lycoming powered 6A ? Not Yet!
> >
> >
>
> >> Homepage: http://www.flyrotary.com/
> >> Archive: http://lancaironline.net/lists/flyrotary/List.html
>
>
-al wick
Artificial intelligence in cockpit, Cozy IV powered by stock Subaru 2.5
N9032U 200+ hours on engine/airframe from Portland, Oregon
Prop construct, Subaru install, Risk assessment, Glass panel design info:
http://www.maddyhome.com/canardpages/pages/alwick/index.html
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