Supersonic aircraft with spike for controlling and reducing sonic boom

Abstract

Method and arrangement for reducing the effects of a sonic boom created by an aerospace vehicle when said vehicle is flown at supersonic speed. The method includes providing the aerospace vehicle with a first spike extending from the nose thereof substantially in the direction of normal flight of the aerospace vehicle, the first spike having a second section aft of a first section that is aft of a leading end portion, the first and second sections having a second transition region therebetween and each of the sections having different cross-sectional areas, the leading end portion of the first spike tapering toward a predetermined cross-section with a first transition region between the predetermined cross-section and the first section. The first transition region is configured so as to reduce the coalescence of shock waves produced by the first spike during normal supersonic flight of the aerospace vehicle. A spike may also be included that extends from the tail of the aerospace vehicle to reduce the coalescence of shock waves produced by the spike during normal supersonic flight of the aerospace vehicle.

1 . A method for configuring and operating an aircraft for minimizing sonic boom effects at ground level during supersonic flight of the aircraft, said method comprising: 
 configuring an aircraft and flying the aircraft at supersonic speed so that in said supersonic flight, a lower profile of the aircraft is presented and generally groundwardly directed;    generating a plurality of different-magnitude pressure disturbances below the aircraft, and radiating therebelow, and controlling the plurality of different-magnitude pressure disturbances generated below the aircraft so that differentials thereamong are sufficiently minimized that ground level sonic boom effects are minimized during said supersonic flight; and    configuring the lower profile of the aircraft so that no stronger pressure disturbances generated below the aircraft and behind a bow shock pressure disturbance caused by the apex of a nose portion of the aircraft propagate at angles sufficient to result in their coalescence with the bow shock prior to reaching ground level during said supersonic flight.    
   
   
       2 . A method for configuring and operating an aircraft for minimizing sonic boom effects at ground level during supersonic flight of the aircraft, said method comprising: 
 configuring an aircraft and flying the aircraft at supersonic speed so that in said supersonic flight, a lower profile of the aircraft is presented and generally groundwardly directed;    generating a plurality of different-magnitude pressure disturbances below the aircraft, and radiating therebelow, and controlling the plurality of different-magnitude pressure disturbances generated below the aircraft so that differentials thereamong are sufficiently minimized that ground level sonic boom effects are minimized during said supersonic flight; and    configuring the lower profile of the aircraft so that no pressure disturbances generated below the aircraft and behind a bow shock pressure disturbance caused by the apex of the nose portion propagate at angles sufficient to result in their coalescence with the bow shock prior to reaching ground level during said supersonic flight.    
   
   
       3 . A method for configuring and operating an aircraft for minimizing sonic boom effects at ground level during supersonic flight of the aircraft, said method comprising: 
 configuring an aircraft and flying the aircraft at supersonic speed so that in said supersonic flight, a lower profile of the aircraft is presented and generally groundwardly directed;    generating a plurality of different-magnitude pressure disturbances below the aircraft, and radiating therebelow, and controlling the plurality of different-magnitude pressure disturbances generated below the aircraft so that differentials thereamong are sufficiently minimized that ground level sonic boom effects are minimized during said supersonic flight; and    controlling the plurality of different-magnitude pressure disturbances generated below the aircraft by selective arrangement of discontinuities in a lower exterior surface of the aircraft and thereby assuring that ground level sonic boom effects are minimized during supersonic flight during said supersonic flight.    
   
   
       4 . A method for configuring and operating an aircraft for minimizing sonic boom effects at ground level during supersonic flight of the aircraft, said method comprising: 
 configuring an aircraft and flying the aircraft at supersonic speed so that in said supersonic flight, a lower profile of the aircraft is presented and generally groundwardly directed;    generating a plurality of different-magnitude pressure disturbances below the aircraft, and radiating therebelow, and controlling the plurality of different-magnitude pressure disturbances generated below the aircraft so that differentials thereamong are sufficiently minimized that ground level sonic boom effects are minimized during said supersonic flight; and    configuring propulsion units mounted upon the aircraft so that pressure disturbances created thereby, below the aircraft, propagate at angles insufficient to result in their coalescence with a bow shock caused by the apex of the nose portion prior to reaching ground level during said supersonic flight.    
   
   
       5 . A method for configuring and operating an aircraft for minimizing sonic boom effects at ground level during supersonic flight of the aircraft, said method comprising: 
 configuring an aircraft and flying the aircraft at supersonic speed so that in said supersonic flight, a lower profile of the aircraft is presented and generally groundwardly directed;    generating a plurality of different-magnitude pressure disturbances below the aircraft, and radiating therebelow, and controlling the plurality of different-magnitude pressure disturbances generated below the aircraft so that differentials thereamong are sufficiently minimized that ground level sonic boom effects are minimized during said supersonic flight; and    positioning all inlets of side-mounted jet propulsion units at above-wing locations thereby assuring that downwardly directed pressure disturbances generated by the inlets is substantially blocked from direct propagation below the lower profile of the aircraft during said supersonic flight.    
   
   
       6 . A method for configuring and operating an aircraft for minimizing sonic boom effects at ground level during supersonic flight of the aircraft, said method comprising: 
 configuring an aircraft so that in flight, with landing gear retracted, a lower profile of the aircraft is substantially linear;    arranging a nose portion of the aircraft so that an apex thereof is coincident with the substantially linear lower profile of the aircraft;    flying the aircraft at supersonic speed and orienting the aircraft during said supersonic flight so that the substantially linear lower profile of the aircraft is oriented substantially parallel to onset airflow;    generating a plurality of different-magnitude pressure disturbances below the aircraft, and radiating therebelow, of lesser magnitude than a plurality of pressure disturbances simultaneously generated above the aircraft and radiating thereabove;    controlling the plurality of different-magnitude pressure disturbances generated below the aircraft so that differentials thereamong are sufficiently minimized that ground level sonic boom effects are minimized during supersonic flight; and    configuring the nose portion of the aircraft so that vertical cross-sections oriented perpendicular to a long axis of the aircraft are substantially round-shaped.    
   
   
       7 . A method for configuring and operating an aircraft for minimizing sonic boom effects at ground level during supersonic flight of the aircraft, said method comprising: 
 configuring an aircraft so that in flight, with landing gear retracted, a lower profile of the aircraft is substantially linear;    arranging a nose portion of the aircraft so that an apex thereof is coincident with the substantially linear lower profile of the aircraft;    flying the aircraft at supersonic speed and orienting the aircraft during said supersonic flight so that the substantially linear lower profile of the aircraft is oriented substantially parallel to onset airflow;    generating a plurality of different-magnitude pressure disturbances below the aircraft, and radiating therebelow, of lesser magnitude than a plurality of pressure disturbances simultaneously generated above the aircraft and radiating thereabove;    controlling the plurality of different-magnitude pressure disturbances generated below the aircraft so that differentials thereamong are sufficiently minimized that ground level sonic boom effects are minimized during supersonic flight; and    configuring the nose portion of the aircraft so that vertical cross-sections oriented perpendicular to a long axis of the aircraft are substantially elliptical-shaped.    
   
   
       8 . The method as recited in  claim 7 , further comprising: 
 orienting a long axis of the substantially elliptical-shaped vertical cross-sections to be substantially vertical.    
   
   
       9 . The method as recited in  claim 7 , further comprising: 
 orienting a long axis of the substantially elliptical-shaped vertical cross-sections to be substantially horizontal.    
   
   
       10 . The method as recited in any one of  claim 1 , further comprising: 
 conducting said supersonic speed flying with landing gear of the aircraft retracted.    
   
   
       11 . The method as recited in any one of  claim 1 , wherein said lower profile is substantially linearly configured.  
   
   
       12 . The method as recited in  claim 11 , further comprising: 
 arranging a nose portion of the aircraft so that an apex thereof is coincident the substantially linear lower profile of the aircraft.    
   
   
       13 . The method as recited in any one of  claim 1 , further comprising: 
 orienting the aircraft during said supersonic flight so that the substantially linear lower profile of the aircraft is oriented substantially parallel to onset airflow to the aircraft.    
   
   
       14 . The method as recited in any one of  claim 1 , further comprising: 
 radiating the generated plurality of different-magnitude pressure disturbances below the aircraft and controlling said radiating pressure disturbances below the aircraft to be of lesser magnitude than a plurality of pressure disturbances simultaneously generated above the aircraft and radiating thereabove.    
   
   
       15 . The method as recited in any one of  claim 1 , further comprising: 
 orienting the aircraft during supersonic flight so that the lower profile of the aircraft is leveled to a substantially horizontal orientation.    
   
   
       16 . The method as recited in any one of  claim 1 , further comprising: 
 configuring the aircraft so that during supersonic flight coalescence of the plurality of different-magnitude pressure disturbances is prevented below the aircraft.    
   
   
       17 . The method as recited in any one of  claim 1 , further comprising: 
 orienting the aircraft during supersonic flight so that an angle of attack of a fuselage of the aircraft approaches zero.    
   
   
       18 . The method as recited in any one of  claim 1 , further comprising: 
 selecting the propulsion units to be jet propulsion units.    
   
   
       19 . The method as recited in any one of  claim 1 , further comprising: 
 configuring a fuselage of the aircraft so that a lower exterior surface thereof establishes the substantially linear lower profile of the aircraft.    
   
   
       20 . The method as recited in any one of  claim 1 , further comprising: 
 configuring the aircraft so that an apex of a nose portion of the aircraft is coincident with the lower profile of the aircraft;    diverting a majority of a plurality of generated different-magnitude pressure disturbances above the aircraft during supersonic flight thereby establishing an asymmetrical distribution of the different-magnitude pressure disturbances about the aircraft; and    controlling a minority of the plurality of different-magnitude pressure disturbances that are diverted below the aircraft so that ground level sonic boom effects are minimized during supersonic flight.    
   
   
       21 . The method as recited in any one of  claim 1 , further comprising: 
 manipulating at least one sonic boom contributing design characteristic of the supersonic flying aircraft to assure that a plurality of groundwardly radiating pressure disturbances do not coalesce, one with another, to form a humanly perceptible and objectionable sonic boom during supersonic flight by the aircraft.    
   
   
       22 . The method as recited in any one of  claim 1 , further comprising: 
 manipulating at least one sonic boom contributing design characteristic of the supersonic flying aircraft to prevent coalescence of a plurality of groundwardly radiating pressure disturbances generated during supersonic flight and thereby establishing a shaped sonic boom signature of the aircraft, at ground level, that is humanly perceptible and non-objectionable to a perceiving person at ground level.