Installation drawing. A drawing that includes all necessary information for a part or an assembly in the final installed position in the aircraft.

Intergranular corrosion. An attack along the grain boundaries of an alloy that commonly results from a lack of uniformity in the alloy structure.

Inductance. The ability of a coil or conductor to oppose a change in current flow.

Inductive reactance. The opposition to the flow of current which inductances put in a circuit.

Inductor. A coil of wire that produces inductance in an electrical circuit.

Insulator. A material that does not conduct electrical current very well or not at all. Examples are glass, ceramic, and plastic.

Ion. An atom or group of atoms in which the number of electrons is different from the number of protons. It is a positive ion if the number of electrons is less than the number of protons, and a negative ion if the number of electrons is greater than the number of protons.

Isometric drawings. A drawing that uses a combination of the views of an orthographic projection and tilts the object forward so that portions of all three views can be seen in one view.

Joule. The amount of work done by a force of one newton when it acts through a distance of one meter.

Kinetic energy. Energy due to motion, defined as one half mass times velocity squared.

Kirchhoff’s Law (voltage). A basic law of electrical currents stating that the algebraic sum of the applied voltage and the voltage drop around any closed circuit is zero.

Lateral stability. The stability about the longitudinal axis of an aircraft; the rolling stability, or the ability of an airplane to return to level flight due to a disturbance that causes one of the wings to drop.

Lever. The simplest machine. There are three basic parts in all levers: the fulcrum “F,” a force or effort “E,” and a resistance “R.”

Load cell. A component in an electronic weighing system that is placed between the jack and the jack pad on the aircraft. The load cell contains strain gauges whose resistance changes with the weight on the cell.

Longitudinal magnetization. The magnetic field is produced in a direction parallel to the long axis of the part. This is accomplished by placing the part in a solenoid excited by electric current.

Longitudinal stability. The tendency for an aircraft nose to pitch up or pitch down, rotating around the lateral axis (wingtip to wingtip).