Definition
The instrument that gives the most direct, immediate, and accurate indication of the airplane's pitch performance for the maneuver being flown. Which instrument fills this role depends on what the pilot is trying to hold constant: the altimeter is the primary pitch instrument in level flight, the vertical speed indicator is primary pitch during a constant-rate climb or descent, and the airspeed indicator is primary pitch during a constant-airspeed climb or descent.
Plain English
The single instrument the pilot watches most closely to judge whether the nose is in the right place for the maneuver. It changes depending on the maneuver — level flight, climb, or descent.
Context Anchor
Seen when learning the primary-and-supporting instrument method for flying by reference to analog cockpit instruments.
Derivation
Primary comes from a Latin word meaning first. Pitch, in aviation, means the airplane’s nose-up or nose-down motion or position. Together, primary pitch instrument means the first instrument used to judge and control that up-or-down nose position.
Why Pilots Care
Correct use prevents altitude and airspeed deviations and reduces the chance of entering an unusual attitude.
Intuition Check
Do not assume primary means the same instrument is always most important. Here, primary means the main reference for this specific part of the maneuver. Do not read pitch as sound or throwing. In this context, pitch means the airplane’s nose-up or nose-down attitude.
Example Sentence 1
Once she leveled off at 6,000 feet, the altimeter became her primary pitch instrument.
Example Sentence 2
When entering a descent, the pilot adjusted pitch by referencing the primary pitch instrument until the target airspeed stabilized.