For the cold side of the MGB, how long after shutdown do you wait to check the oil servicing?

The correct answer is that you wait for 2 hours or more to check the oil servicing on the cold side of the Main Gearbox (MGB) after shutdown. This time frame is necessary to allow the oil to completely settle back into the sump, ensuring an accurate measurement of the oil level. If the oil is checked too soon after shutdown, it may still be circulating or have residual movement, resulting in an artificially high reading.

Allowing a sufficient amount of time helps to avoid potential miscalculations about the oil level, which is critical for maintaining proper lubrication and preventing damage to the gearbox components. Proper servicing intervals are essential for the safe and efficient operation of the aircraft, ensuring that the MGB functions effectively once the aircraft is operational again.