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##  Weight 

Weight is a measure of the force of gravity acting upon the mass of the WSC aircraft. Weight consists of everything directly associated with the WSC aircraft in flight: the combined load of the total WSC aircraft (wing, wires, engine, carriage, fuel, oil, people, clothing, helmets, baggage, charts, books, checklists, pencils, handheld global positioning system (GPS), spare clothes, suitcase, etc.). 

During gliding flight, weight is broken down into two components. The component that opposes the lift, acting perpendicular to flight/glide path, and the component that opposes the drag and acts in the direction of the fl ight/glide path. During gliding flight, this component of weight is the weight component providing the forward force which some call thrust for gliding fl ight. 

During gliding, straight, and descending in unaccelerated fl ight: 

Lift (L) and Drag (D) components = Resultant force (RF) = Weight (W) 

Total Drag (D$_{T}$) = Weight component (W$_{D}$) in the direction of fl ight 

Lift (L) = Weight component (W$_{L}$) that opposes lift 

Similar to airplanes, gliders, and PPC during gliding fl ight, less lift is required because the resultant force composed of lift and drag provides the force to lift the weight. In other words, in gliding flight, drag helps support the weight. [Figure 2-19] 

##  Thrust 

At a constant air speed, the amount of thrust determines whether an aircraft climbs, flies level, or descends. With the engine idle or shut off, a pilot is descending or gliding down. Maintaining a constant airspeed, when enough thrust is added 

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to produce level flight, the relative wind stream becomes horizontal with the Earth and the AOA remains about the same. As described for the airplane in the Pilot’s Handbook of Aeronautical Knowledge, thrust equals total drag for level fl ight. [Figure 2-20] 

When in straight and level, unaccelerated fl ight: 

At a constant airspeed, when excess thrust is added to produce climbing flight, the relative air stream becomes an inclined plane leading upward while AOA remains about the same. The excess thrust determines the climb rate and climb angle of the fl ightpath. [Figure 2-21] 

When in straight and climbing, unaccelerated fl ight: 

Lift (L) = Component of weight that opposes lift 

Weight (W) = Resultant force (F$_{R}$) of lift (L) and excess thrust to climb (T$_{E}$) 

Thrust = Total drag (D$_{T}$) plus rearward component of weight 

Lift (L) = Weight (W) 

Thrust = Total Drag (D$_{T}$) 

