Definition
A multi-pointer pneumatic altimeter with an adjustable barometric scale (Kollsman window) that allows the pilot to set the current local altimeter setting in inches of mercury or hectopascals, so the instrument displays altitude referenced to that pressure datum.
Plain English
An altimeter you can adjust to the current air pressure setting given by ATC or a weather report, so it shows the right altitude for where you are flying today.
Context Anchor
Seen during cockpit instrument checks, before takeoff, and whenever a pilot sets the altimeter to the current local pressure setting.
Derivation
Called "sensitive" because, unlike older fixed altimeters, it responds to small pressure changes and can be fine-tuned by the pilot to the current barometric setting. The word "sensitive" here means "responsive to small adjustments," not "delicate."
Why Pilots Care
Accurate altitude is essential for avoiding terrain, complying with airspace rules, and maintaining safe separation from other aircraft.
Intuition Check
Sensitive does not mean fragile or easily damaged here. It means the altimeter can detect small pressure changes and turn them into altitude indications.
Example Sentence 1
Before takeoff, the pilot set 30.02 in the Kollsman window of the sensitive altimeter to match the current altimeter setting.
Example Sentence 2
After passing through a cold front, the pilot reset the sensitive altimeter to maintain accurate altitude.