With aircraft, other factors affecting optimum cruise altitude include payload, center of gravity, air temperature, humidity, and speed. This altitude is usually where the higher ground speeds, the increase in aerodynamic drag power, and the decrease in engine thrust and efficiency at higher altitudes are balanced. Typical cruising airspeed for a long-distance commercial passenger aircraft is 475â500 knots (878â926 km/h; 546â575 mph).
The process of saturation and slumping continues, leading to failure of dam. c) Structural Failure: About 25% of failure is attributed to structural failure, which is mainly due to shear failure causing slide along the slopes. The failure may be due to:
Sediment in rivers can also shorten the lifespan of dams and reservoirs. When a river is dammed and a reservoir is created, the sediments that used to flow along with the relatively fast-moving river water are, instead, deposited in the reservoir. This happens because the river water flowing through the reservoir moves too slowly to keep sediment suspended -- the sediment settles to the bottom of the reservoir.