10. The Installed Jet Engine
Unlike a free standing jet engine, once installed in an Aircraft which is caused to move because of its action when used, the engine is required to perform two entirely different physical functions simultaneously. Each of these functions is equally critical to the overall economic performance of the Aircraft. The first has already been dealt with, namely, the efficient conversion of chemical fuel energy into Air Mass Motion Energy.
The second function is that in terms of fundamental dynamics the engine is required to be regarded and treated as an integral part of the Aircraft's structure. Consequently, in flight, the Air Mass caused to accelerate through it is no longer to be considered as part of the jet engine's Cycle, but, as an integral part of the Aircraft's Air Mass Motion System. As a direct consequence, the engine is no longer simply required to act as a jet engine but, also, provide the ACTION half of the Aircraft's AIR MASS MOTION SYSTEM. The REACTION half of the Jet Engine's physical working cycle as a Jet Engine, i.e., the accelerated Air Mass Flow Force it has created throughout its length, becomes, and is caused to form, the ACTION half (Air Mass Motion System No.1) of the Aircraft's, Air Mass Motion System. From this point forward, in terms of fundamental dynamics we are no longer concerned with the physical efficiencies of the physical jet engine (these are already set as determined by the efficiencies of the physical systems comprising the jet engine itself). The potential thrust at the disposal of the Aircraft has already been determined, as has how long that power can last which depends upon the level and rate of physical power actually used and delivered per unit mass of fuel load in unit time. However, this physical potential of the Aircraft to do work in flying and for how long, does not determine the actual speed or range that it is actually capable of achieving. Consequently, its actual range and flight speed is not finally determined by the aerodynamic efficiency of the Aircraft's airframe inclusive of its engines, but, by the Motion Efficiency of the Aircraft's, Air Mass Motion System.
Consider, in terms of fundamental physics, and as far as the Aircraft is concerned, a unit of thrust force delivered to it is in fact of exactly the same physical value no matter if it is produced and delivered by a pure,bypass, variable cycle, fan, ram jet or rocket type of engine. Consequently, we are here, less concerned in terms of fundamental motion physics with how the thrust force delivered to the Aircraft/engine's mounting bolts is produced, because this is the solely the realm of the jet engine manufacturer. However, in terms of fundamental motion physics as determined by motion law we must be more concerned with the actual manner of how the thrust force is both delivered and utilised by the Aircraft.
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