Definition
A reference table published by the International Civil Aviation Organization that shows how many feet to add to a published altitude to correct for altimeter under-reading caused by colder-than-standard air. The table is organized by reported surface temperature and by height above the altimeter setting source, and is used by pilots to calculate a corrected indicated altitude that ensures actual obstacle clearance during instrument approaches in cold conditions.
Plain English
A lookup chart that tells you how much extra height to add to your altimeter reading when it is very cold outside, because cold air makes the altimeter show you higher than you actually are.
Context Anchor
Seen in instrument flying when checking altitude corrections for cold-weather approaches, minimum altitudes, and obstacle clearance.
Derivation
ICAO stands for International Civil Aviation Organization, the group that sets many worldwide aviation standards. “Cold temperature error” refers to the altitude error caused when cold air makes the altimeter reading less representative of the aircraft’s true height above the ground.
Why Pilots Care
Failure to apply the corrections can result in descent below safe altitudes and controlled flight into terrain.
Grounding Statement
On a very cold day, an aircraft showing 3,000 feet on the altimeter may actually be lower above the ground than it would be on a standard-temperature day.
Intuition Check
The “error” is not a pilot mistake or a broken instrument. It is a predictable altitude difference caused by cold air, and the table helps estimate the needed correction.
Example Sentence 1
With a reported surface temperature of minus 30 degrees Celsius, the captain consulted the ICAO Cold Temperature Error Table and added 300 feet to the final approach fix altitude.
Example Sentence 2
In temperatures twenty degrees below standard, the table indicated an additional 500 feet should be added to all altitudes on the approach plate.