Which type of switch is commonly used for ignition in model rockets?

The momentary push button switch is commonly used for ignition in model rockets because it allows the ignition circuit to be completed only while the button is pressed. This feature is critical for safety, as it prevents accidental ignition and ensures that the rocket motor ignites only when the launch button is actively engaged by the user. The user has control over when the ignition occurs, reducing the risk of unintentional launches.

In contrast, other switches such as toggle switches and rotary switches can remain in a position that keeps the ignition circuit closed, which poses a safety hazard by increasing the chances of an unexpected ignition. Additionally, a ball switch typically relies on movement (such as the position of a ball within a housing) to complete a circuit, and is not the most reliable choice for a clear and controlled operation during an ignition process. Hence, the momentary push button switch is the preferred choice for ensuring both safe and intentional ignition in model rocketry.