Statistical Prediction Model for Glass Breakage from Nominal Sonic Boom Loads.

Abstract : A statistical model was developed which can be used to estimate the probability of glass breakage from sonic booms as a function of their nominal overpressure. Other parameters which can be taken into account in breakage probability calculations with this model include window size, aircraft vector, boom duration, and whether the glass was previously in good condition or cracked. A model window population has been devised from available data which includes the distributions of dynamic amplification factors and breaking pressures for seven window types. Provision has been made in the model to treat .61% of the window population as cracked glass. From computer generation of histograms from test data, the distribution of both sonic boom stresses and glass strengths were found to be lognormal. By use of the model, it was estimated that there would be 1.1 breaks per million panes in good condition boomed at a nominal overpressure of 1 psf. This estimate agrees well with sonic boom claims data. (Author)