Abstract: A surge arrester comprising a stack of a plurality of cylindrical varistor blocks (10), preferably made of metal oxide, which are arranged one after the other in the axial direction of the varistor blocks between an upper end electrode (11) and a lower end electrode (12) and surrounded by an elongated, electrically insulating external casing (19) of rubber or other polymeric material. The end electrodes (11, 12) are interconnected by means of at least three clamping members (15) of insulating material to achieve the required contact pressure between the different elements (10-14) in the stack. Between the lower end electrode (12) and the first block (10) in the stack of varistors, there is arranged a pivot means comprising a centrally placed pivot member (17), projecting from the lower end electrode (12), said pivot member (17) making contact with a pressure plate (14), resting against the lowermost block (10) in the stack of varistors, to achieve articulation in all transverse directions.

Abstract: Powder gases issuing from the muzzle of an aircraft-mounted gun are initially deflected to one side of the line of fire by a mouthpiece in the form of a length of pipe coaxially mounted directly in front of the muzzle and having an elliptical mouth extending all across it and along it from a pointy front end of it to a short distance in front of its rear end. The gases are further deflected to a discharge direction away from sensitive parts of the aircraft by a set of guide plates arranged outside the mouthpiece and spaced apart at regular intervals along the line of fire. Inner surface portions of the guide plates, proximal to the extended axis of the gun barrel, are parallel to the direction of local gas flow out of the mouthpiece, and the guide plates are curved so that their outer surface portions, which cooperate to define slot outlets, extend in said discharge direction and are parallel to one another.