For RAT to provide electrical power, what is the minimum speed (Vmin)?

For RAT to provide electrical power, what is the minimum speed (Vmin)?

• A. 130
• B. 250
• C. 160
• D. 230

Answer: (A)

Airflow is what makes the RAT spin. The turbine must reach a certain rotational speed before the attached generator can deliver usable electrical power. That threshold speed is called Vmin—the lowest indicated airspeed at which the RAT can provide electrical power. Below Vmin, the turbine can’t spool fast enough to generate power; at Vmin and above, power becomes available (subject to the electrical load). So among the options, the value that matches that minimum operating speed is the one that allows the RAT to supply electrical power. Higher speeds will also work, but the question asks for the minimum speed required.

Airflow is what makes the RAT spin. The turbine must reach a certain rotational speed before the attached generator can deliver usable electrical power. That threshold speed is called Vmin—the lowest indicated airspeed at which the RAT can provide electrical power. Below Vmin, the turbine can’t spool fast enough to generate power; at Vmin and above, power becomes available (subject to the electrical load). So among the options, the value that matches that minimum operating speed is the one that allows the RAT to supply electrical power. Higher speeds will also work, but the question asks for the minimum speed required.