Reducing the Accident Rate

"Snowbird" wrote in message
om...

For our type anyway, supposedly the accidents can be traced to pilot
judgement.

No doubt pilot judgment is a major cause of accidents.

It's a pretty simple aircraft to maintain, anyway, Sen. Inhofe's propeller
notwithstanding. That was a simple case of his A&Ps not following the
maint. manual procedure, not of insufficient money on maint.

It may be a simple airplane to maintain, but does that mean there are not
accidents due to insufficient maintenance? Even something as simple as a
worn tire can lead to an accident. Lots of "simple" airplanes are flown
well beyond TBO or have pencil-whipped annuals or even pencil-whipped engine
overhauls.

--------------------
Richard Kaplan, CFII

www.flyimc.com

"Richard Kaplan" wrote
It may be a simple airplane to maintain, but does that mean there are not
accidents due to insufficient maintenance?

I think that's really the wrong question. The right question is - are
the majority of the accidents due to insufficient maintenance? Is it
the single biggest cause? Second biggest cause? Or is it down in the
decimal dust?

My experience suggests decimal dust.

Michael

"Michael" wrote in message
om...

My experience suggests decimal dust.

I think it is hard to know how many accidents are due to maintenance issues
by reading NTSB reports, just like they are inaccurate for other reasons
you stated.

It is one thing for the NTSB to determine that an airplane was "airworthy"
and "in annual." It is another to hangar fly and hear stories of engine
failures in an airplane where it is local knowledge that a given mechanic
does pencil-whip annuals or that a given airplane owner often cut corners on
maintenance.

Anecdotally I hear about a lot less engine failures among people flying
engines within TBO by hours and also under 10 years old than with older
engines... it would be interesting to tabulate the data someday in a
statistically valid manner.


--------------------
Richard Kaplan, CFII

www.flyimc.com

"Richard Kaplan" wrote
My experience suggests decimal dust.
I think it is hard to know how many accidents are due to maintenance issues
by reading NTSB reports

I concur, and do not base my opinion on NTSB reports.

Anecdotally I hear about a lot less engine failures among people flying
engines within TBO by hours and also under 10 years

That's because few airplanes reach hourly TBO within 10 years. My
experience indicates that those engines fail about as often - there
are just fewer of them.

it would be interesting to tabulate the data someday in a
statistically valid manner.

Yes it would. The very fact that the manufacturers COULD do it if
they chose, and choose not to, indicates that they don't want the
facts known. That suggests to me that the failures (a) happen far
more often than is generally believed and (b) are not prevented by
regular factory overhauls.

Fundamentally, I think most failures are a design problem rather than
a maintenance problem. So why are we still using clearly obsolete
designs? FAA.

Michael

"Michael" wrote in message
om...


Fundamentally, I think most failures are a design problem rather than
a maintenance problem. So why are we still using clearly obsolete
designs? FAA.

What piston engine design would be more reliable? (Economics make turbine
engine comparisons unfair, even if turbines are more reliable -- and I am
not certain that they are.)

I have experienced a lot more engine problems driving cars than flying
airplanes for sure.

Experimental airplanes do not seem to have any lower incidence of engine
failures anecdotally, nor do I recall reading any data to suggest there
exists a more reliable experimental piston engine design.


--------------------
Richard Kaplan

www.flyimc.com

"Richard Kaplan" wrote
What piston engine design would be more reliable? (Economics make turbine
engine comparisons unfair, even if turbines are more reliable -- and I am
not certain that they are.)

First off, turbine engines are not out of the questions at all. The
reason they are so incredibly expensive has a lot to do with the FAA
and milspecs. Second, turbine engines are inherently more reliable -
there are far fewer moving parts, and no reversals of direction. In
addition, they separate the combustion stages (suck, squeeze, bang,
blow) in space rather than in time - and that means only a relatively
small part of the engine has to be tough enough to accomodate the most
difficult portion of the cycle. In other words, pound for pound the
turbine will always be more reliable.

Second, we've learned a lot about piston engine reliability in the
past half century. Little of that has made it into aircraft engine
designs. For example, separate cylinders are disasters. There's not
sufficient mechanical stability, so everything moves too much. Note
that the two modern aviation piston engines - the Thielert and Orenda
- have abandoned that nonsense.

That's just one example. There are countless others in the ignition,
fuel, and other systems.

I have experienced a lot more engine problems driving cars than flying
airplanes for sure.

Driving cars made in the last 20 years? I find that amazing.

Experimental airplanes do not seem to have any lower incidence of engine
failures anecdotally, nor do I recall reading any data to suggest there
exists a more reliable experimental piston engine design.

Experimentals are amateur-designed. The engine installations are
amateur-designed too. The very fact that after the first 50 hours are
flown off the accident rate appears to even out with the certified
airplanes should suggest to you what a disaster the FAA-mandated
professional engineering is. Amateurs can do almost as well working
in their garages.

Michael

For example, separate cylinders are disasters.

What are "separate cylinders" and what's the alternative? (unless you mean the
wankel)

Jose


--
(for Email, make the obvious changes in my address)

"Michael" wrote in message
om...

First off, turbine engines are not out of the questions at all. The
reason they are so incredibly expensive has a lot to do with the FAA
and milspecs. Second, turbine engines are inherently more reliable -

So why hasn't someone developed an inexpensive, reliable turbine engine for
experiental airplanes?


sufficient mechanical stability, so everything moves too much. Note
that the two modern aviation piston engines - the Thielert and Orenda
- have abandoned that nonsense.

What planes are these used in? Do you have any references about these?

Driving cars made in the last 20 years? I find that amazing.

Well as one example I experienced a sudden catastrophic engine failure this
year in my 1999 Toyota minivan. An engine cooling fan circuit malfunctioned
and the engine overheated while driving in a snowstorm. I pulled over right
away but nonetheless the engine block had melted and I needed a new block
and new cylinders... $8000 in warranty work repairing the engine due to
failure of a $125 part.

Experimentals are amateur-designed. The engine installations are
amateur-designed too. The very fact that after the first 50 hours are
flown off the accident rate appears to even out with the certified
airplanes should suggest to you what a disaster the FAA-mandated
professional engineering is. Amateurs can do almost as well working
in their garages.

Well can anyone do BETTER than FAA certified airplanes? Who in your mind
can produce an airplane with a more reliable engine than an FAA certified
engine?



--------------------
Richard Kaplan

www.flyimc.com

"Richard Kaplan" wrote:
I have experienced a lot more engine problems driving
cars than flying airplanes for sure.

Another Jaguar driver!
--
Dan
C172RG at BFM

Michael wrote:

Yes it would. The very fact that the manufacturers COULD do it if
they chose, and choose not to, indicates that they don't want the
facts known.

What makes you think the manufacturers could do that? Many, if not most engine
repairs and overhauls are not performed by the manufacturer, so they have no little
data. You're expecting a manufacturer to spend hundreds of thousands of dollars to
research a report which provides no benefit to the manufacturer. The fact that they
"choose not to" merely indicates that they don't want to waste their money.

George Patterson
In Idaho, tossing a rattlesnake into a crowded room is felony assault.
In Tennessee, it's evangelism.