Since the introduction of the jet engine and its increasing refinement,

fuel began to assume a much more prominent role in

the overall design of the aircraft [1-1]. Fuel has now reached at

least an equal design consideration as the engine and airframe

[1-2]. There are several reasons for this increased importance of

the fuel in the overall system. In addition to its essential function

of providing the energy necessary for flight [1-3], the fuel will act

as the primary heat sink required for cooling the aircraft and its

equipment [1-4]. In many future systems, the fuel will constitute

over fifty percent (50%) of the total weight [1-5] of the system

and the fuel cost may well be as high as fifty percent (50%) of the

direct operating cost (Figure. 1.1.). The purpose of this mini book

is to summarize the progress made to date in the development of

these advanced hydrocarbon fuels and to submit the necessary

requirements for future hydrocarbon fuels for the aerospace industry.

The idea of regular supersonic flight of air-breathing weapon

systems has become a reality within previous years and the

advancement of even faster systems will continue [1-7]. This incredible

boost in flight speed has led to significant increases in

the relative value of the fuel to the general system [1-8]. In the

period of the piston engine, airplane designers were more concerned

with the engine and the airframe rather than with the fuel

[1-9]. The choice of fuel to be utilized in the airplane was often

of secondary significance [1-9]. All things considered, with the

presentation of the jet engine motor and its expanding change,

the fuel began to assume significantly more fundamental capacity

in the general plan till the point has now achieved where the

fuel has obtained at least proportionate status with the motor

and the airframe [1-10].