AHRS Initialization takes approximately how much time on the ground and how much time in flight?

• A. 70 seconds on the ground; 10-35 seconds in flight
• B. 60 seconds on the ground; 5-15 seconds in flight
• C. 90 seconds on the ground; 20-40 seconds in flight
• D. 45 seconds on the ground; 70 seconds in flight

Answer: (A)

AHRS initialization is the process of aligning the attitude and heading reference system using sensor data after power-up. On the ground, the aircraft is stationary, so the system relies on static measurements from gravity, the magnetic field, and biased sensors to establish a stable reference, which takes about 70 seconds. In flight, dynamic motion provides additional information that helps the system converge faster, so initialization can complete in roughly 10 to 35 seconds. Knowing when initialization finishes is important because attitude data becomes more reliable once the AHRS is fully aligned. These times are typical, approximate values used in training materials.