July 2018 Issue

Twenty Miles?

The FAA recommends staying 20 miles away from thunderstorms. Does that include microbursts, virga and gust fronts?

The 20-mile clearance policy is a safe number and probably easy to stipulate, but scale and definitions make it challenging. For every fully visible and developed severe thunderstorm, there are even more smaller cells or building storms that may or may not grow to thunderstorm level. Sometimes a curtain of rain is just a curtain of rain. Other times, it can be hiding something much bigger due to the lurking cumulonimbus that has built up above the overcast.

To continue reading this entire article you must be a paid subscriber.

Subscribe to Aviation Safety

The monthly journal of risk management and accident prevention, is packed with useful, timely information on basic and advanced technique, accident analysis and, most important, practical articles on how you can develop the judgment that will keep you in the air and out of the NTSB's files.

Already subscribe but haven't registered for all the benefits of the website? Click here.

Subscriber Log In

Forgot your password? Click Here.