O-213 Magazine Loading Density Detonation Estimation

An analysis has been conducted to develop a method to estimate critical loading density conditions that, after the deflagration ignition of the munitions in a magazine, will lead to transition to detonation of these munitions. The method assumes that transition takes place due to the increased rate of deflagration burning as a result of increasing internal magazine Quasi Static Pressure (QSP). This method uses an estimated explosive equivalency, energetics mass and magazine volume in order to calculate the resulting magazine quasi-state pressure (QSP). The burn rate behavior of the energetics contained in the magazine is then used as an indicator of whether a deflagration to detonation (DDT) would occur at the calculated QSP. A test case is presented using high performance anti-armor missiles. The results indicate that modern anti-armor missiles that pass the fast cook-off (FCO) test are unlikely to DDT, as extremely high loading densities that are not practically achievable would be required to cause DDT. The results also show that IM packaging venting is vital for reducing munitions IM response violence. These are conservative estimates, as they assume all of the energetic material is burnt to calculate QSP and they do not account for magazine venting, which would greatly reduce the achieved internal magazine pressures. This analysis is not applicable to munitions that have Type I or Type II responses from fast cook-off testing that will undoubtedly DDT in a magazine fire event.