Definition
A decompression sickness condition caused by nitrogen bubbles forming in the blood and lodging in the small vessels of the lungs after a rapid reduction in atmospheric pressure. Symptoms include a deep burning chest pain, a persistent cough, and difficulty breathing. Chokes is a serious form of altitude-induced decompression sickness and requires immediate descent and recompression treatment.
Plain English
A dangerous reaction the body can have at high altitude when nitrogen comes out of the blood as bubbles and gets stuck in the lungs, causing chest pain and trouble breathing.
Context Anchor
Seen in engine starting procedures and carburetor descriptions, especially on older or small engines.
Derivation
The condition is called 'chokes' because the symptoms feel like being choked — a tight, burning chest and the inability to draw a full breath.
Why Pilots Care
Correct use prevents hard starting and flooding; leaving the chokes out after start can cause rough running or engine damage.
Intuition Check
Chokes are not the same as wheel chocks. Chokes restrict airflow or flow; chocks are blocks placed against wheels to keep an aircraft from moving.
Example Sentence 1
After the cabin lost pressure at FL350, the first officer reported deep chest pain and a dry cough — classic signs of chokes — and the crew began an immediate emergency descent.
Example Sentence 2
Once the engine warmed up, the pilot pushed the chokes fully in for normal operation.