How is the oil level of an air and oil shock strut typically checked?

The method for checking the oil level of an air and oil shock strut typically involves releasing the air and visually inspecting the filler plug. This process is essential because it allows for a direct observation of the oil level inside the strut. When air pressure is released, it ensures that there's no pressure holding the oil up in the strut, which can give an inaccurate reading. By removing the filler plug, maintenance personnel can see the oil level myself or use a dipstick if one is available, providing an accurate assessment of whether the strut has the recommended amount of oil.

The other options, while potentially relevant to certain maintenance procedures, do not directly address the method of checking the oil level. Checking the pressure gauge relates more to understanding the air pressure within the strut than to the oil level itself. Feeling for heat on the cylinder does not provide any reliable information regarding the oil level, since temperature does not correlate directly with the amount of oil present. Consulting the maintenance manual can be useful for general guidance or specifications, but it does not physically check the oil level, making it more of a secondary step rather than the actual method used to verify the oil level in the shock strut.