Patent ID: 7861966

Claim:
A method of reducing sonic boom generated when an aircraft having a wing forward undersurface section curving down to produce weak shock compression waves and an aft undersurface section curved up to receive and re-reflect reflected shock compression waves changes its velocity from one supersonic velocity to another supersonic velocity, the method comprising: flying said aircraft at a first supersonic velocity generating a free stream airflow having a free stream airflow first velocity across an undersurface of a wing of said aircraft; providing a nozzle below and transverse the wing; generating via said nozzle an essentially uniform planar jet flow aft in the general line of flight below and transverse of the wing of said aircraft said jet flow having a jet flow first velocity in excess of the free stream airflow first velocity, wherein vortices are generated between said jet flow and said free stream flow, whereby shock compression waves from a forward undersurface portion of said wing are received and reflected by said vortices to an aft undersurface portion of said wing; changing said aircraft velocity to a second supersonic velocity different from the first supersonic velocity generating a free stream airflow second velocity across the undersurface of said wing different from the free stream airflow first velocity; and adjusting a jet flow velocity to a second jet flow velocity in response to said free stream second velocity, said jet flow second velocity for continuing to maintain said vortices, whereby weak shock compression waves from the forward undersurface portion of the wing continue to reflect from the vortices; wherein the jet flow first velocity is selected such that the difference between the jet flow first velocity minus of and the free stream airflow first velocity is not greater than Mach 2, and wherein the jet flow second velocity is selected such that the difference between the jet flow second velocity and the free stream airflow second velocity is not greater than Mach 2 for continuing to maintain said vortices; and wherein the jet flow has a first mass flow rate at the jet flow first velocity, comprising adjusting the mass flow rate of the jet flow and adjusting the first jet flow velocity by varying the mass flow rate in response to variations in free stream airflow and pressure and varying the jet flow first velocity in response to changes in the first velocity of the free stream airflow for maintaining the difference between a jet flow velocity and a velocity of the free stream airflow to at a level not greater than Mach 2.