FAA Ground School Practice Test

How should 4,500 feet MSL be stated to ATC?

1. "FOUR THOUSAND, FIVE HUNDRED."

2. "FOUR THOUSAND FIFTY."

3. "FOUR FIVE ZERO ZERO."

4. "FOUR THOUSAND FOUR HUNDRED."

The correct answer is: "FOUR THOUSAND, FIVE HUNDRED."

When communicating altitude to Air Traffic Control (ATC), the correct format involves clearly stating the altitude in thousands and hundreds. In this case, "4,500 feet MSL" should be articulated as "FOUR THOUSAND, FIVE HUNDRED." This method minimizes confusion and ensures that the information is conveyed clearly and accurately. Using the thousands-hundreds format is essential because it aligns with standard aviation communication practices, which often utilize a systematic method of stating numbers for clarity. This approach helps in reducing the likelihood of miscommunication, especially in busy airspace or during critical phases of flight. Other methods, such as saying "FOUR FIVE ZERO ZERO," while technically correct in expressing the digits, do not follow standard ATC communication protocols, which prefer the tens and hundreds format. Similarly, stating "FOUR THOUSAND FIFTY," would incorrectly imply an altitude of 4,050 feet instead of 4,500 feet, leading to potential safety issues. "FOUR THOUSAND FOUR HUNDRED" also indicates an entirely different altitude, that of 4,400 feet. Thus, precise and accepted phrasing is vital for effective communication with ATC.