Question

The wingspan of a glider is to be altered by doubling the size, thereby doubling the lift in order to increase the maximum number of passengers. It is argued that this will cause the flight to be unaffected because the drag, and weight are each doubled as well. Why is this arguement incorrect? Note: Neglect the fuselage.

Answer 1

let us see the problem in detail

Wingspan of glider is altered by doubling the size.

looking at various experimental data it can be deduced that on increasing the wing area drag and lift both are increased in a proportional way(doubled in this case). and ratio of drag to lift is equal to ratio of thrust to weight hence both thrust and weight are doubled.

the problem with the argument is that it says flight is unaffected. As by increasing the weight means total payload carrying capacity is increased. hence the objective to increase the maximum number of passengers is increased by increasing the weight to be carried by lift force.