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Old 26th Oct 2019, 07:22
  #168 (permalink)  
beardy
 
Join Date: Nov 2000
Location: UK
Age: 69
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Originally Posted by Easy Street


The study considers internal drag of the engine only and acknowledges that overspill of air from the intake can affect airframe drag. As airflow through the windmilling engine is reported as 3x greater than the seized engine, that’s potentially a lot of air to redirect. In a podded engine with aerodynamically shaped lips I can quite imagine that a ‘blob’ of slower air in the intake would act as quite an effective fairing to divert surplus airflow around the nacelle in streamlined fashion. What I know from experience is that the angular, aerodynamically-complex maw of the Tornado didn’t like having a seized engine inside it... probably not helped by most of the spilled air immediately colliding with the external stores and landing gear (admittedly not as much of a problem for the Hawk, but probably still more than for a podded type).
It's rare for modern engines to seize without damage, any damage would affect the internal drag!
At least in the Tornado there wouldn't have been excessive asymmetry.
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