Book Review:Maintenance/overhaul guide to Lycoming aircraft engines, Christy

Not a substitute for the Overhaul manual



This book contains an overview of maintenance and overhaul for the
WWII-era-technology air-cooled Lycoming engines which unfortunately
still power the vast majority of personal aircraft in the world. It is
useful to people who have worked on other engines, to provide an
overview of the procedures and tooling needed, but it contains little
information not in the Lycoming or military manuals, which are
available at reasonable cost in reprint form from suppliers in addition
to the extremely expensive one from the folks at 652 Oliver Street.

You will need to have the factory book with the most recent Table of
Limits if you are working on this as a certificated aircraft engine. If
you are using it as an experimental or airboat powerplant (are you sure
you really want one of these overpriced museum pieces??) it's not
necessary but can't be urged strongly enough because the first 'oops'
will cost you a lot of money.

Joe Christy was a good writer who turned out a lot of TAB-G/L books,
apparently for beer money, but he has been deceased-he lived to a
considerable age-for several years now. So there are things that aren't
covered in this book he probably would have. But by and large the
Lycoming is still the same engine it was at the beginning of the
postwar lightplane boom, and so this book is just as useful as it ever
was-okay supplemental reading or for the armchair mechanic, but not the
definitive (if dense) factory manual.

"Paul" wrote:


This book contains an overview of maintenance and overhaul for the
WWII-era-technology air-cooled Lycoming engines which unfortunately
still power the vast majority of personal aircraft in the world.

Why, and for whom, is that unfortunate?
--
Alex -- Replace "nospam" with "mail" to reply by email. Checked infrequently.

Paul, your unfortunate derision of Lycoming (and I assume Continental
also) engines shows your bias and your lack of knowledge... There are
actual, real world reasons why the certificated engines you deride
continue to be the engines of choice of the manufacturers of
certificated aircraft...

Denny

Gene Kearns wrote:


This is typical "engineer" mentality.
I'd guess what you describe below to be a marketing mentality rather
than an engineering one.

If a product can be made more complex, or if it can be squeezed for
one more 1/2% of power, or if it could be installed in a smaller space
or made smaller somehow, or if it could run off of some boutique fuel,
it would absolutely obsolete everything coming before, regardless of
the original product's history.
Whether engineering or marketing driven, isn't a push for continual
improvement, even to the point of occasional failures like you point
out due to "overpushing", not desirable?

Some of these engines may not be that far from a 1937 tractor engine,
but, you know what? 65+ years later, we still haven't found anything
affordable and reliable enough to replace them.... AND if they were
sold for what they were *worth* they probably sell for less than $1000
per cylinder, new..... but that is another story....

I guess "worth" is subjective. They are worth far more than that to a
lot of pilots who fly behind them. And if pilots suddenly decided that
they would only pay $1,000 per cylinder, I wonder if any would be
made? I suspect that the increased market at that price would be small
enough that they could never get the economies of scale to manufacture
for that price.
--
Alex -- Replace "nospam" with "mail" to reply by email. Checked infrequently.

Gene Kearns wrote:

On Wed, 22 Dec 2004 11:14:50 -0500, alexy wrote:

Some of these engines may not be that far from a 1937 tractor engine,
but, you know what? 65+ years later, we still haven't found anything
affordable and reliable enough to replace them.... AND if they were
sold for what they were *worth* they probably sell for less than $1000
per cylinder, new..... but that is another story....

I guess "worth" is subjective. They are worth far more than that to a
lot of pilots who fly behind them. And if pilots suddenly decided that
they would only pay $1,000 per cylinder, I wonder if any would be
made? I suspect that the increased market at that price would be small
enough that they could never get the economies of scale to manufacture
for that price.

Then by the same logic, that 8 cylinder engine in your automobile is
"worth" $40,000+.
I don't see how that is the same logic. People are willing to pay
$20k+ for a 4-cyliner aircraft engine, but I doubt if any of them
would be willing to pay $40k for an 8-cylinder auto engine. So for
them, the aircraft engine is worth $5k+ per cylinder, while the auto
engine is not.

How do you define "worth"?

It is hard to make the economy of scale argument
and the "these things haven't changed in 50 years" argument at the
same time. The second year you go into production you have your
tooling and a track record.

First, I wouldn't make the "these things haven't changed in 50 years"
argument. No question that the changes haven't been as dramatic as in
other engines based on this Pre-WWII technology (the internal
combustion engine), but it's a matter of degree.

Secondly, if the tooling for the annual production of 100,000 units of
product x were just 500 copies of the tooling for producing 200 units
per year, this argument would have merit. But I am not aware of any
manufacturing processes that work that way.


If we forget that these are aircraft engines and just look at the fact
that they are machined castings and forgings.... there is no way we
can justify the astronomical price tags....

Well, there is liability insurance, testing, and above all, the law of
supply and demand.
1) People are willing to pay those prices,
2) companies making these products have assessed the market and
determined that lowering prices would not sell enough additional units
to increase profits
3) companies with the engineering and manufacturing expertise to
create competitive products have for the most part decided that they
can't produce them inexpensively enough to attract enough market share
to make a profit, and
4) the few companies who have tried to enter the market with
competitive products have proven the others in point 3 right.

What kind of "justification" do you have in mind? By all means, if you
can make a profit building and selling them for less, put together a
business plan and go talk to venture capitalists! g

--
Alex -- Replace "nospam" with "mail" to reply by email. Checked infrequently.

The manufacturers of certificated aircraft pay LyCon prices because the
only alternative until very recently was an Allison or P&W turboprop at
ten times the cost. I'm not sure any of the other supposedly
certificated engines being talked of are 1) actually certificated in
the U.S, and 2) actually shipping. The Zoche and DynaCam were thinly
veiled efforts to pimp up some venture capital; neither had any real
desire to produce engines.

Homebuilders use these same engines because most homebuilders today
just want to fly and are "building" as a dodge around type
certification: most lack fabrication skills or any desire to
experiment. Look at Richard Van Grunsven, who is making a lot of money
on the RV kits. If people will pay those prices for sheet aluminum
and assorted widgets why should he get his airplane certificated and
tool up and manufacture them? His margins are as high as a certificated
lightplane, he is making a lot of money with relatively little work.

If the Lycoming or Continental engine were really more reliable than
commodity general purpose engines, they'd be used in many other
applications. They are 1930s designs that if not protected by
certification would have been out of production for decades. General
purpose production engines have been installed in aircraft, usually by
people with a lack of resources in manufacturing and design, and yet
flown pretty well. If a company like Mercury Marine chose to get
involved in powerplants for experimental aircraft, they could put
Lycoming out of that market segment in a couple of years.

From: Gene Kearns
Date: Wed, 22 Dec 2004 10:07:18 -0500
Local: Wed, Dec 22 2004 7:07=A0am
Subject: Book Review:Maintenance/overhaul guide to
This is typical "engineer" mentality.

If a product can be made more complex, or if it can be squeezed for
one more 1/2% of power, or if it could be installed in a smaller space
or made smaller somehow, or if it could run off of some boutique fuel,
it would absolutely obsolete everything coming before, regardless of
the original product's history.

There are enough engineering failures to underscore this mind set.
I'll give you two..... Continental's Tiara engine and Lycoming's
experience with the GSIO-720-A1A.

Some of these engines may not be that far from a 1937 tractor engine,
but, you know what? 65+ years later, we still haven't found anything
affordable and reliable enough to replace them.... AND if they were
sold for what they were *worth* they probably sell for less than $1000
per cylinder, new..... but that is another story....

The Continental Tiara was an example of ignoring the published
literature. Any gear designer could tell them that 2:1 is the worst
ratio because the same teeth see each other every other rev. It's in
all the books. They tried to use the cam gear as a reduction gear, a
stupid idea.

I have no experience with geared 720s but I remember well the TIGO-541
and the GSIO-480, both of which were marvels of trouble. The 480 had
an oddball mechanical injection system used nowhere else.

If Lycoming or Continental had to make their ridiculous contraptions
work in anything except an airplane, they would probably quit and go
home. No one ever mentions that the reason the O-290-G engines were
available cheaply until modern times is that they were an absolute pain
in the ass in their original homes. Continental was smarter than to
try to sell the IOL-550 as a sport boating engine, even though many
custom Chevys sold for as much as the Continental did in aircraft trim.
Twenty years of ski and fishing boat experience have convinced me that
given a professionally engineered reduction drive a Chevy or Ford V8 is
a lot more reliable than any engine with bolt on cylinders and a split
crankcase.

From: Richard Riley
Date: Wed, 22 Dec 2004 16:52:54 -0800

Local: Wed, Dec 22 2004 4:52 pm

Subject: Book Review:Maintenance/overhaul guide to Lycoming
aircraft engines, Christy



On 22 Dec 2004 15:52:35 -0800, "Denny" wrote:

:
If the Lycoming or Continental engine were really more reliable than
:commodity general purpose engines, they'd be used in many other
:applications. They are 1930s designs that if not protected by
:certification would have been out of production for decades. General
urpose production engines have been installed in aircraft, usually by
eople with a lack of resources in manufacturing and design, and yet
:flown pretty well. If a company like Mercury Marine chose to get
:involved in powerplants for experimental aircraft, they could put
:Lycoming out of that market segment in a couple of years

..

How about a car company? I mean, if a company that produced high
performance automotive engines got into the business, they'd own it,
right? Especially if they had experience with air cooled engines, so
you wouldn't have the weight or complexity of a liquid cooling system.
They'd use parts that were common to the auto engines, so they'd have
the economy of scale thing going for them And it would help if they
did an opposed engine - you have to see over the cowl, after all, so
opposed or inverted engines have an advantage.

I know, let's get Porsche to get into the aircraft engine business!

_________________________________

Nice try.

Porsche did this very thing of course, calling it Porsche Flight Motors
out of Galesburg, Ill. As you well know.

Your attempt at sarcasm brings up a lot of facts:

1. A 911 Porsche engine in automotive configuration costs as much as a
Lycoming to overhaul. No liability, no certification, just the
willingness of Porsche people to pay stupid prices. Very much as simple
as that.

2. The cam chains have always been trouble on the 911 engine. They
denied it until blue in the face, but the PFM engines had gears.

3. Porsche no longer builds air cooled engines, neither does
Deutz...only H-D, Lyc and Teledyne Continental, purveyors of overpriced
junk to yuppies. As Dave Blanton said, all engines are liquid cooled.
Either by glycol around the valves or raw fuel through them.

4. Porsche would only sell their doubly overpriced-it was quite a bit
more than a Lycoming!-PFM to OEM buyers, of which only one existed,
namely Mooney.

5. You could see over the cowl a lot better with an engine with a
reduction drive putting the crank well below the propeller line and
still be able to have the induction on top of the engine where it
belongs. Additionally, the prop drive could be conveniently isolated
from the crank so that in the event of a gear up landing or noseover,
the engine would not need to be majored.

6. I never see Porsche engines in marine, drag, or circle track racing
and there are no ads for Porsche parts in the hot rod magazines they
sell at the 7-11. Porsches in racing are limited to high dollar road
racing, which Americans could generally care less about unless they are
loaded rich kids or actors like Haywood or Newman.

In rec.aviation.owning Richard Riley wrote:
On 22 Dec 2004 15:52:35 -0800, "Denny" wrote:

:If the Lycoming or Continental engine were really more reliable than
:commodity general purpose engines, they'd be used in many other
:applications. They are 1930s designs that if not protected by
:certification would have been out of production for decades. General
urpose production engines have been installed in aircraft, usually by
eople with a lack of resources in manufacturing and design, and yet
:flown pretty well. If a company like Mercury Marine chose to get
:involved in powerplants for experimental aircraft, they could put
:Lycoming out of that market segment in a couple of years.

How about a car company? I mean, if a company that produced high
performance automotive engines got into the business, they'd own it,
right? Especially if they had experience with air cooled engines, so
you wouldn't have the weight or complexity of a liquid cooling system.
They'd use parts that were common to the auto engines, so they'd have
the economy of scale thing going for them And it would help if they
did an opposed engine - you have to see over the cowl, after all, so
opposed or inverted engines have an advantage.

I know, let's get Porsche to get into the aircraft engine business!

Porsche was in the aircraft business; ever heard of the Porsche Mooney?

--
Jim Pennino

Remove -spam-sux to reply.

Gene Kearns wrote:

On Wed, 22 Dec 2004 16:56:38 -0500, alexy wrote:


Then by the same logic, that 8 cylinder engine in your automobile is
"worth" $40,000+.
I don't see how that is the same logic. People are willing to pay

How do you define, "willing." If you have a certificated aircraft with
a certificated engine... your "will" has nothing to do with it.

Well, unless someone forced those planes on the owners against their
will, they in all likelihood wrote a check (maybe begrudgingly, but
definitely of their own free will) in exchange for that plane, the
cost of which included the engine.
--
Alex -- Replace "nospam" with "mail" to reply by email. Checked infrequently.