A stabilizer that can be adjusted in flight to trim the airplane, thereby allowing the airplane to fly hands-off at any given airspeed.

• A. Adjustable Stabilizer
• B. Fixed Stabilizer
• C. Passive Stabilizer
• D. Automatic Stabilizer

Answer: (A)

Trimming the airplane to fly hands-off at a chosen airspeed is done by adjusting the stabilizer’s angle to create the right pitching moment. An adjustable stabilizer lets you change that angle in flight, so once you’ve set the trim for a specific airspeed (or flight condition), the airplane can maintain its pitch with minimal effort from the pilot. A fixed stabilizer can’t be altered in flight, so it can’t be trimmed for different speeds or conditions. A passive stabilizer isn’t adjustable by the pilot for trim, and an automatic stabilizer describes a system that trims automatically, which isn’t the standard manual trim setup. That’s why the adjustable stabilizer is the correct choice.