The Barber–Layden–Power effect (BLP effect or colloquially Bleep) is a blast wave phenomenon observed in the immediate aftermath of the successful functioning of air-delivered high-drag ordnance at the target.  In common with a typical blast wave, the flow field can be approximated as a lead shock wave, followed by a self-similar subsonic flow field.  The phenomenon appears to adhere to the basic principles of the Sedov solution.