No, it is not possible to break the sound barrier with a typical RC (Radio Control) jet. Breaking the sound barrier, which is approximately 343 meters per second (or 1,235 kilometers per hour) in dry air at sea level, requires an aircraft to overcome significant aerodynamic and engineering challenges.
Achieving supersonic speeds involves dealing with issues such as intense aerodynamic forces, shockwaves, and structural integrity. While full-scale military jets and specialized aircraft have been designed to break the sound barrier, RC jets are not typically designed or capable of reaching those speeds. They are typically smaller in size, have limited power, and are not designed to withstand the extreme forces associated with supersonic flight.
Attempting to push an RC jet beyond its design limits and into supersonic speeds could lead to catastrophic failure, loss of control, or even the destruction of the aircraft. It is important to operate RC jets within their intended capabilities and within the limits defined by the manufacturer for safety reasons.