Which condition triggers a required flight test after alteration?

• A. An Alteration That May Appreciably Change Its Flight Characteristics
• B. A Cosmetic Paint Job
• C. A Minor Hardware Upgrade
• D. A Change of Radio Callsign

Answer: (A)

When an alteration may appreciably change how the glider flies, a required flight test is triggered. This test verifies that the modification hasn’t introduced any unexpected handling, stability, or performance issues and that the aircraft still meets safety and design limits. Cosmetic paint jobs don’t affect aerodynamics or weight distribution in a meaningful way, so they don’t require a flight test. A minor hardware upgrade, if it doesn’t alter flight characteristics, likewise doesn’t mandate a flight test. Changing the radio callsign is purely administrative and has no impact on flight performance.