Definition
An abrupt halt of an aircraft engine's rotation, typically caused by a propeller strike, prop tip contact with the ground or water, or seizure of internal components. Sudden stoppage requires a mandatory engine teardown inspection per the manufacturer's instructions, because the rotational energy of the propeller and crankshaft, when stopped instantly, can damage the crankshaft, accessory gears, counterweights, and other internal parts even if no external damage is visible.
Plain English
When an engine stops turning instantly instead of winding down -- usually because the propeller hit something. Even if the engine looks fine, the inside parts may be bent or cracked, so the engine must be taken apart and inspected before it can be flown again.
Context Anchor
Seen in maintenance records, propeller-strike discussions, accident reports, and decisions about whether an engine must be inspected before further flight.
Derivation
Combines 'sudden' (from Latin subitaneus, meaning happening without warning) and 'stoppage' (the act of stopping). The pairing emphasizes the violent, external-force nature that sets it apart from ordinary engine failures.
Why Pilots Care
Often requires a full engine teardown or detailed inspection because internal components such as the crankshaft and bearings may be damaged even if the engine appears to run afterward.
Analogy
It is like a spinning fan blade hitting a solid object and stopping at once. The blade may be the obvious contact point, but the sudden force can damage parts deeper inside the motor.
Grounding Statement
If a moving propeller hits something and stops almost instantly, the force can travel into the engine and damage internal parts.
Intuition Check
Do not read sudden stoppage as just a quick engine shutdown. In aviation maintenance, it means an abnormal hard stop that may cause hidden damage.
Example Sentence 1
After the nosewheel collapsed and the propeller struck the runway, the engine experienced sudden stoppage and had to be removed for a full teardown inspection.
Example Sentence 2
Following the bird strike, maintenance performed a sudden stoppage inspection to check for a bent crankshaft.