What is the first component of the M67 Sight Unit?

The first component of the M67 Sight Unit is the horizontal plane lever. This component plays a crucial role in achieving accurate targeting and aligning the sight unit with the firing platform. It allows for adjustments that help ensure that the sight is level, which is essential for precise aiming, particularly when engaging targets at various distances or angles.

Utilizing this lever correctly enables the gunner to account for any cant in the mounting system, ensuring that the line of sight is aligned with the intended point of impact. This alignment is critical for a successful engagement, as even slight deviations at the sight can result in significant errors at the target.

Other components, such as the fine deflection scale and deflection adjustment knob, are important for making fine adjustments once the initial leveling has been established by the horizontal plane lever. Similarly, the elevation vial assists in vertical alignment but follows after confirming the horizontal alignment with the plane lever. Understanding the hierarchy and function of these components is essential for effective operation of the M67 Sight Unit.