David
I have been following a website  that is promoting Mazda type rotary
engines for light  aircraft. With only 3 moving parts, there are a lot
less  things to go wrong. You almost always make it home and they  are
cheap to fix. They started talking about using acetone as  an
additive to speed up the combustion so that all the fuel is  burned
from the sparking of 2 spark plugs. They were speaking  of a fast
moving combustion front and I thought that this may  be an ideal home
for Butanol. Butanol for rotary engines. I  have been asked how much
it costs. It would seem to me that  with the way that gas is going,
it may be cheaper to use  butanol in planes. Can you help me and
would you like to speak  with Paul Lamar at the above website?

Peter  Duffecy

David,

Few things packs such  an energy punch as gasoline and diesel or jet
kerosene, and  you will be hard pressed to get the distance you are
getting  from it, from much of anything else. The fuel of choice is  those
products, and the discussion of acetone, Hydroxy,  multiple
sparkplugs  etc is merely ways to ignite the  fuel load as quick as
possible.

Once burning, it  will not burn quicker, but if it could be ignited in
more  places than one, the process can be shortened.

However,  what packs the energy, and what does the grunt work, is
gasoline, diesel or jet kerosene.

It is of course possible  to burn all kinds of fuel in any combustion
engine, all kinds  of gases, or burning liquids.....however the BTU
out of most  other alternatives....to say it frankly.....sucks.

Certain combinations of methods or compounds can enhance
performance , or economy, a NOS bottle will not only make you  laugh,
but it will pep up the engine pretty much. A Top Fuel  dragster run
on so much nitro and alcohol, that the  compression stroke is close
to hydraulic lock. A smaller  ammount of Propane in diesel trucks
have, reportedly  beneficial effect on the economy, etc.

Yes an airplane  engine , ( or an engine in any vehicle) can run, as you
suggest on Butanol, ...or Propane...or Hydrogen gas, ...or Alcohol  ...or
basically anything that will burn and can be fed into  the engine, ...
but run the numbers of volume and weight  needed in order to be energy
comparable, and you will be  surprised....not to mention the way some
of it has to be  stored, in pressurized bottles.  For the size, and
weight, you have to come up with some pretty good energy  packing
product to beat gasoline, diesel or jet  kerosene.

You might be able to do a 6 hr flight with  gasoline, while you are bound
to do an hour and a half with  alternative fuel. then once you land,
it is a matter of  getting into a taxi with your gas canisters and
getting
it filled somewhere, if you want to get home  again.

Just because it is possible, and the fuel in  question have a couple
of desirable features ...like  ....perhaps....clean
burning....doesn't mean it is a viable  way to go.

Alcohol, you need roughly twice the tank size  if we compare that energy
with gasoline, so you have a choice,  either you keep your tank size
intact, but fly only half as  far, or fly as far, but double your
tank size...take a  pick.

Same equation has to be looked into for any fuel  alternative.

An equation that works for a city bus, it  will not necessarily work for
an aircraft.

We have not even touched the issue of existing infrastructure
yet.....land in Wyoming and when the fuel truck get to you, ask  him
if he has a special on Hydrogen today.

Roger



For your information;

A number of  years ago Detroit Diesel had an experimental program
running  a
modified 6V-92 bus engine on M100. When you fired them up they ran  like a
blown alcohol or fuel dragster. Then after going for a drive  they
would idle
like a normal engine for a couple of  minutes. Then the combustion chamber
cooled a bit and back to the  rough idle. They had a controller with
LED's on
it that  flashed when it turned on glow plugs (taken from the 5.7 Chev
diesel).
It needed the glow plugs because the high heat of  vaporization took
the heat
of compression out and it would  not run without them.

Medicine Hat, Alberta, Canada had two of  these as they have two methanol
plants that were closed. They were  interested as a market for methanol
would
get employment  going. They finally gave up on these engines. At first the
engine  life was only about 50,000 miles. Detroit finally got it up to
100,000
with lubricity additives in the fuel. The large quantity of  methanol
sprayed
into the cylinders was washing the oil  off the walls. When they
converted them
back to diesel,  they had trouble with restarting the engines. Turns
out  the
head castings were different internally to retain heat and when  they
were shut
off the fuel boiled in the heads and vapor  locked.

Bottom line with this is; to change something is not  necessarily easy
and many
things will likely need  changing. Granted butanol is fairly close to
gasoline
in  heat content and required infrastructure, but only a lot of trial
and error
will be required.

Dale  Davies



Peter Duffecy,

What is the website you are  referring to that promotes rotary engines in
aircraft?   Thanks.

Tom