Recent Technical Developments: Ground Lighting Requirements with Details of Chance Brothers' Productions—New Armstrong‐Siddeley Engines Available to Purchase

The general trend in aero‐lighting apparatus which is purely illuminative seems rather towards improvement of existing types than to the evolution of larger or novel types, an illustration of which is landing floodlight apparatus as usually marketed. This has been developed to a point where 10 kw. filament lamps and dioptric lenses are Used with an approximate beam intensity of 700,000 c.p. It seems that this type of unit will, except for modifications and improvements, continue to be the standard landing floodlight. The fourth order, 500 mm., dioptric lens floodlight, using a 5 kw. lamp with a beam intensity of 160,000 c.p. approximately, is being developed for aerodromes in countries where atmospheric conditions are more favourable than England, e.g., Mesopotamia, South Africa.