Question

When must the pilot enter the initial position (LAT/LONG) for IRS alignment?

a) Before engine start
b) During taxi
c) After takeoff
d)When GPS position is not available

Answer 1

The pilot must enter the initial position for IRS alignment before engine start, ensuring the IRS has the correct reference point for navigation.

Step-by-step explanation:

The pilot must enter the initial position (LAT/LONG) for Inertial Reference System (IRS) alignment before engine start. This is a critical step in the pre-flight procedure because it allows the IRS to accurately calculate the aircraft's position and navigate effectively once airborne. Without this initial position fix, the IRS would not have a reference point from which to begin its tracking, potentially leading to navigation errors. Although the IRS can be aligned in flight, it is a standard operating procedure to align it on the ground prior to engine start, ensuring the system has the correct position information before any movement occurs.