Ex Parte FEULNER - Page 4



          Appeal No. 2002-0538                                                        
          Application 09/220,468                                                      

          stator vanes.  The engine also comprises a thrust modulator which           
          operates without the necessity of reducing engine speed.  In                
          Uehling’s words,                                                            
               [a]s shown schematically in FIG. 3, the turbojet                       
               engine 10 is provided with a bypass pipe 24 having a                   
               valve 26 interposed therein.  One end of the bypass                    
               pipe 24 is connected to the compressor 14 near its                     
               discharge end, and the valve 26 is actuated by the                     
               pilot to bleed off a certain percentage of compressor                  
               discharge air thereby reducing the mass flow though the                
               combustion system 16 and the turbine 18.  A portion of                 
               this bleed air is provided to a turbine cooling flow                   
               path 27 from which it is delivered to various                          
               components of the turbine 18 to cool the same.  . . .                  
               . . . [T]he remaining portion of the bleed flow                        
               within the pipe 24 is piped from compressor discharge                  
               to the turbojet tail pipe 19 forward of the exhaust                    
               nozzle 20 and downstream of the turbine 18 . . .                       
               through thrust spoiling means, generally designed by                   
               the numeral 28, as shown in FIG. 3.                                    
               As shown in both FIG. 3 and FIG. 4, the thrust                         
               spoiling means 28 take the form of a plurality of swirl                
               inducing nozzles 30 positioned within a manifold 32, to                
               which the bleed pipe 24 is connected.  By means of the                 
               swirl inducing nozzles 30 the bleed flow is introduced                 
               into the tail pipe 19 so as to maximize swirl of the                   
               gas flowing within the tail pipe 19, thereby                           
               significantly increasing the tail pipe pressure and                    
               momentum losses and reducing the nozzle thrust                         
               coefficient, which, in turn, causes an instantaneous                   
               and additional increment of thrust reduction [column 3,                
               line 54, through column 4, line 14].                                   
               Figure 3 shows Uehling’s bypass pipe 24, which channels                
          cooling air from the compressor 14 to the turbine 18 via flow               
          path 27, as communicating with the compressor at a position                 
          adjacent the tip clearance area of a row of rotating blades.  As            

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