In modern aircraft, which instrument largely replaced the turn-and-slip indicator?

• A. Attitude indicator
• B. Turn coordinator
• C. Heading indicator
• D. Vertical speed indicator

Answer: (B)

The main idea is how pilots get a quicker, more complete picture of turning efficiency and coordination. The turn coordinator was designed to replace the older turn-and-slip indicator because it senses both the rate of turn and roll information, not just the yaw rate. Its gyroscope is mounted at a slight cant, so as you roll into a turn the instrument responds immediately, showing the aircraft’s rate of turn plus roll in a way that’s easy to read. A tiny airplane symbol moves to indicate how fast you’re turning, and the slip-skid ball still shows whether you’re coordinated, helping you keep the turn smooth and coordinated.

Attitude indicators, heading indicators, and vertical speed indicators all convey other aspects of flight—pitch/attitude, heading, and vertical speed, respectively—and don’t provide the integrated turn rate plus roll information that the turn coordinator offers.