Re: If jet engines are so good -- light, fewer parts which rotate & don't recip

Greetings:

Another name for jet engines is gas turbines. Gas turbines are in use today in the
Navy's non-nuclear powered ships, the Army's M1 Abrams tank and are now being used
to effecently generate electricity in cities such as New York where back up power
to the power grid is required. In these applications the turbines drive electric
generators that are used for propulsion and auxiliary power.

During the late 1950s and early 1960s the major automobile manufacturers all had
turbine powered automobiles. The Chrysler Turbine Program began with an orange-red
1954 Plymouth built in the fall of 1953. The outside appearance of the Turbine
Specials was like standard production models with the exception of certain trim,
hubcaps, special medallions and scripts. In December of 1958 the second generation
turbine car was driven from Detroit to New York, and Chrysler engineers claimed a
marked improvement in fuel consumption. The second-generation turbine developed
200 horsepower- twice that of the first generation engines-and hp ratings on gas
turbines actually reflect greater torque and power than similar number ratings
of a piston engine.

The Chrysler automobiles can be seen on the following Web Site along with remarks
by George J. Huebner, Jr., Director of Research, Chrysler Corporation, at a meeting
in Detroit with representatives of the press, radio and television on Tuesday,
April 12, 1966. Mr. Huebner was considered the father of Chrysler's turbine cars.
In this message he presents details about the advantages and problems encountered
with their 50 gas turbine powered test cars.

http://www.turbinecar.com/sia/sia57.htm

A sleek, lightweight passenger train, the Turbo-Train, entered service in 1968 in
the United States and Canada. The TurboTrain was lighter, faster, quieter, smoother
and more reliable than conventional trains -and cheaper to run. The TurboTrain,
conceived on aerodynamic principles, and was powered by aircraft-type gas turbine
engines, was designed by United Aircraft Corporation. It was developed and marketed
by Surface Transportation Systems, Sikorsky Aircraft Division.

http://www.sikorskyarchiv es.com/train.html

Advantages and Disadvantages of Gas Turbines

Gas turbine engines have a great power-to-weight ratio compared to reciprocating
engines. That is, the amount of power you get out of the engine compared to the
weight of the engine itself is very good. Also, gas turbine engines are smaller
than their reciprocating counterparts of the same power.

The main disadvantage of gas turbines is that, compared to a reciprocating engine
of the same size, they are expensive. Because they spin at such high speeds
and because of the high operating temperatures, designing and manufacturing
gas turbines is a tough problem from both the engineering and materials standpoint.
Gas turbines also tend to use more fuel when they are idling, and they prefer a
constant rather than a fluctuating load. That makes gas turbines great for things
like transcontinental jet aircraft and power plants, but explains why they
are no longer being used in automobiles and railroad locomotives.

What's happening today?

Today, fuel cell powered electric/gas hybrid automobiles are being developed and
gas turbines are again being considered for these vehicles. You can read about
these developments on the Scientific American Magazine web site Beyond Batteries

http://www . sciam.com/explorations/122396explorations.html

Best regards, Your Mad Scientist
Adrian Popa