The term “stress” is often used interchangeably with the word “strain.”

The degree of deformation of a material.

A material’s internal resistance, or counter force, that opposes deformation.

The stress that resists a force that tends to pull something apart.

The stress that tends to shorten or squeeze aircraft parts.

The stress that produces twisting.

The stress that resists the force tending to cause one layer of a material to slide over an adjacent layer.

A combination of compression and tension.

The forward force produced by the power-plant/propeller.

Opposes the downward force of weight

An axis extends through the aircraft from nose to tail, with the line passing through the CG

An axis extends across the aircraft on a line through the wing tips, again passing through the CG.

An axis passes through the aircraft vertically, intersecting the CG.