What are the five stress that affect aircraft?

1. Aerodynamic stresses

Aerodynamic stresses are caused by the forces of air flowing over the aircraft's surfaces. These stresses can be divided into two categories:

* Symmetrical stresses are caused by forces that are evenly distributed over the aircraft's surfaces. These stresses include lift, weight, and thrust.

* Unsymmetrical stresses are caused by forces that are not evenly distributed over the aircraft's surfaces. These stresses include drag, side force, and rolling moment.

2. Structural stresses

Structural stresses are caused by the internal forces that act on the aircraft's structure. These forces include:

* Bending stresses are caused by forces that tend to bend the aircraft's structure.

* Torsional stresses are caused by forces that tend to twist the aircraft's structure.

* Shear stresses are caused by forces that tend to slide the aircraft's structure.

3. Thermal stresses

Thermal stresses are caused by changes in temperature. These stresses can be caused by:

* Solar heating can cause the aircraft's skin to expand, which can lead to buckling.

* Cold temperatures can cause the aircraft's structure to contract, which can lead to cracking.

4. Acoustic stresses

Acoustic stresses are caused by sound waves. These stresses can be caused by:

* Engine noise can cause the aircraft's structure to vibrate, which can lead to fatigue failure.

* Turbulence can cause the aircraft's structure to buffeting, which can also lead to fatigue failure.

5. Ground handling stresses

Ground handling stresses are caused by the forces that are applied to the aircraft when it is on the ground. These forces include:

* Weight of the aircraft can cause the aircraft's structure to sag.

* Towing the aircraft can cause the aircraft's structure to be twisted.

* Loading and unloading the aircraft can cause the aircraft's structure to be damaged.