Definition
A method of construction in which an aircraft or engine is built from self-contained sections (modules) that can be removed, replaced, or overhauled independently of the rest of the unit.
Plain English
The aircraft or engine is built in chunks, and each chunk can be taken off and swapped without tearing the whole thing apart.
Context Anchor
Seen in aircraft maintenance, repair, and construction discussions, especially when describing how a fuselage, wing section, tail section, or other major part is built and replaced.
Derivation
From the Latin modulus, meaning a small measure or unit. A modular structure is one built from standardised units that fit together, so each unit can be handled on its own.
Why Pilots Care
Modular construction means that when one section of an engine or airframe needs overhaul, only that module is pulled and serviced. This shortens downtime and lowers maintenance cost, which directly affects aircraft availability and operating economics.
Intuition Check
Do not read modular structure as meaning the aircraft is temporary, light-duty, or like a toy kit. Here it means the aircraft is built from major sections designed to fit together as part of the approved structure.
Example Sentence 1
The turbine engine's modular structure allowed the maintenance crew to replace the hot section without removing the compressor.
Example Sentence 2
Mechanics prefer modular structures because a single damaged panel can be exchanged without disturbing adjacent sections.