Which option represents the tachometer Green Arc range at sea level?

Which option represents the tachometer Green Arc range at sea level?

• A. 1,800-2,300 RPM
• B. 1,850-2,150 RPM
• C. 1,700-2,200 RPM
• D. 1,900-2,350 RPM

Answer: (D)

The green arc on the tachometer shows the RPM range in which the engine is designed to run during normal, safe operation. Staying within this range helps keep the engine and propeller operating smoothly, efficiently, and without excessive wear. For sea-level operation, the typical safe continuous range is about 1,900 to 2,350 RPM. The lower limit around 1,900 RPM ensures the engine runs smoothly without roughness or stalling, while staying above idle so the engine isn’t overworked. The upper limit near 2,350 RPM keeps you below the maximum continuous, reducing the risk of overheating, excessive fuel use, or stress on the engine and propeller. Ranges that are significantly lower risk rough running or stalling, and ranges that go well above 2,350 RPM risk over-stressing the engine. So the green arc that sits roughly between 1,900 and 2,350 RPM is the correct representation for sea-level operation.

The green arc on the tachometer shows the RPM range in which the engine is designed to run during normal, safe operation. Staying within this range helps keep the engine and propeller operating smoothly, efficiently, and without excessive wear.

For sea-level operation, the typical safe continuous range is about 1,900 to 2,350 RPM. The lower limit around 1,900 RPM ensures the engine runs smoothly without roughness or stalling, while staying above idle so the engine isn’t overworked. The upper limit near 2,350 RPM keeps you below the maximum continuous, reducing the risk of overheating, excessive fuel use, or stress on the engine and propeller.

Ranges that are significantly lower risk rough running or stalling, and ranges that go well above 2,350 RPM risk over-stressing the engine. So the green arc that sits roughly between 1,900 and 2,350 RPM is the correct representation for sea-level operation.