Which types of aircraft must be equipped with G.P.W.S. and Glide slope deviation alerting system?

The correct answer is that turbine-powered airplanes must be equipped with a Ground Proximity Warning System (GPWS) and a glide slope deviation alerting system. This requirement stems from safety regulations aimed at preventing controlled flight into terrain (CFIT) accidents, which are more prevalent in turbine-powered aircraft due to their operational characteristics and typical flight environments.

Turbine engines are often found in larger aircraft that operate on commercial routes, which necessitates higher safety standards. The GPWS helps pilots avoid unintentional descent towards the ground, while the glide slope deviation alerting system provides critical information regarding the aircraft's approach to a runway.

Piston-powered airplanes, gliders, and smaller general aviation aircraft typically do not have the same level of operational complexity or risk factors associated with commercial turbine aviation, and thus are not universally required to be equipped with these systems. The emphasis on turbine-powered aircraft reflects a targeted approach to enhance safety where the need is most pronounced.