FAA Aircraft Dispatcher (ADX)Navigation and ATCHard
A tower controller reports the Runway Visual Range (RVR) for Runway 27L as 4000. What is the approximate equivalent visibility in statute miles for planning purposes?
- A1/4 statute mile
- B1/2 statute mile
- C3/4 statute mile
- D1 statute mile
Show answer & explanationAnswer & explanation
Correct answer: C. 3/4 statute mile
Using the standard RVR-to-visibility conversion table, an RVR value of 4000 feet corresponds to approximately 3/4 statute mile visibility. Other common reference points are: RVR 1600 = 1/4 SM, RVR 2400 = 1/2 SM, RVR 5000 = 1 SM.
Why the other options are wrong
- A. 1/4 SM corresponds to an RVR of about 1600 feet, not 4000.
- B. 1/2 SM corresponds to an RVR of about 2400 feet, not 4000.
- D. 1 SM corresponds to an RVR of about 5000 feet, not 4000.
RVR to Visibility Conversion
Runway Visual Range (RVR) in feet can be approximately converted to statute mile visibility using a standard FAA conversion table for flight planning and approach minimums.
- RVR 1600 ft ≈ 1/4 SM
- RVR 2400 ft ≈ 1/2 SM
- RVR 4000 ft ≈ 3/4 SM
- RVR 5000 ft ≈ 1 SM
- RVR 6000 ft ≈ 1 1/4 SM
Memory trick: '16-24-40-50-60 → 1/4-1/2-3/4-1-1&1/4' — count up by quarters as RVR climbs.