The gyroscope provides initial attitude reference for the missile, 0.1 seconds after the trigger is squeezed, high pressure nitrogen gas forces the gyroscope to rotate how fast?

• A. 60,000 rpm
• B. 42,000 rpm
• C. 10,000 rpm
• D. 5,000 rpm

Answer: (B)

A gyroscope stores attitude information by spinning so fast that its angular momentum keeps the reference stable as the missile moves. When the trigger is squeezed, a burst of high-pressure nitrogen gas quickly spins the rotor up to a speed that lets the guidance system establish a reliable reference within about 0.1 seconds. That speed is around forty-two thousand revolutions per minute because it provides enough angular momentum for rapid stabilization without overloading the gyro or the system.

If it spun much faster, like sixty thousand rpm, the components would endure more stress and energy use, with diminishing returns for this short-time reference. If it spun much slower, say five thousand or ten thousand rpm, there wouldn’t be enough angular momentum to resist disturbances during the early phase of flight, making the initial attitude reference less reliable.