The matter to justify a choosing of the test conditions when studying the lightning stroked aircraft by the insulated scaled model is considered. The selectivity for striking points under the High Voltage (HV) pulses of different polarity and waveform was experimentally been determined. The negative polarity voltage pulses have been concluded to be preferably used. A new method for conducting such tests with the help of a physical laboratory model of the charged thunderstrom cell has been proposed. This method allows an induced both free-gained charge on the tested model objects to be modelled. A preliminary experimental study has been carried out.