Definition
Airframe components — typically in the landing gear, fuselage belly, or seat mounts — that are engineered to deform progressively on impact, absorbing energy and reducing the forces transmitted to the occupants.
Plain English
Parts of the airplane that are designed to crumple in a crash so the people inside take less of the hit.
Context Anchor
Seen in emergency landing and crash-survivability discussions, especially when considering how impact forces are reduced.
Derivation
From 'crush' (to deform under pressure) plus 'structure' (the load-bearing parts of the airframe). The name signals the design intent: these parts are meant to be sacrificed in a crash so the cabin around the occupants stays more intact.
Why Pilots Care
It directly increases the chance of surviving a hard landing or crash by reducing peak g-forces on occupants and critical systems.
Analogy
A car’s front end is designed to crumple so the people inside are slowed down less violently. A crushable structure in aviation serves the same basic purpose: it gives way to absorb energy.
Grounding Statement
In a hard impact, anything that crushes gradually can reduce the force passed to the cabin.
Intuition Check
Do not read “crushable” as meaning weak or unsafe. Here it means designed or useful for absorbing impact energy by giving way.
Example Sentence 1
The instructor explained that the landing gear is part of the airplane's crushable structure, designed to absorb energy during a hard touchdown.
Example Sentence 2
Certification tests confirmed that the crushable structure kept seat loads within human tolerance limits.