What is the first action to take during an engine fire on the ground?

The correct action during an engine fire on the ground is to keep cranking the engine while maintaining 50-60 RPM, as this helps facilitate a potential engine restart and allows for the flight controls to remain operational. Maintaining RPM can also aid in cooling the engine and might prevent further damage, depending on the situation.

When facing an engine fire on the ground, maintaining control of the helicopter is critical to ensure safety. The potential for exacerbating the situation increases if the helicopter is allowed to become fully inoperative. This approach allows the pilot to remain in command while assessing the fire's status and gathering time to make the best decision moving forward, which could involve safely exiting the helicopter if necessary.

Shutting off the fuel and mixture immediately is also an important step but typically comes after ensuring some form of control is retained. Activating the rotor brake and attempting to extinguish the fire with onboard equipment could lead to a lack of control or focus when an immediate response is necessary to stabilize the situation.