Traps for the unwary

Now your focus is tactical. Decisions may need to be made quickly. All of them affected by your qualifications, experience, proficiency, and judgment.

When it comes to steering clear of clouds, the regulations can be helpful guidelines. That goes double for VFR-only pilots. For those of us flying in instrument meteorological conditions, there are more specialized rules. But VFR rules have an air of compromise, and the regs can leave a lot to the imagination. Ultimately, you will be the final judge when it comes to flying in and around clouds and adverse conditions.

Cloud separation and visibility rules for VFR flying (FAR 91.155) amount to a bewildering list of requirements based on airspace. You must stay clear of clouds and have three statute-mile visibility if flying in Class B airspace. For Classes C, D, and E (below 10,000 feet msl) you’ll need the same three-mile visibility and stay at least 500 feet below, 1,000 feet above, and 2,000 feet horizontally from clouds. There are other rules dealing with Class G airspace, and still more if flying in Class E at 10,000 feet msl and above.

As for takeoffs, landings, or pattern entries in Classes B, C, D, and E, you’ll need a ceiling of at least 1,000 feet and a ground visibility of at least three statute miles or, if ground visibility isn’t available, a flight visibility of at least three statute miles. At airports in Class G airspace, you can fly at less than 1,200 feet above the surface even if the visibility is less than three statute miles (but no less than one statute mile at night) and you stay in the traffic pattern within one-half mile from the runway.

But wait, there’s more. Under special VFR rules (91.157) you can fly in an airport’s controlled airspace below a lofty 10,000 feet msl—as long as you have an ATC clearance, remain clear of clouds, and flight visibility is at least one mile. For more details, check out FAR 91.157.

By now you must have come to the obvious conclusion that “textbook” VFR can translate into multiple meanings. To put it bluntly, flying VFR may well be legal—but it can be unsafe at the same time. Special VFR’s clear-and-one sounds a lot like instrument meteorological conditions, with plenty of opportunities to inadvertently fly into the soup and lose orientation. Yes, moving maps and FIS-B/SiriusXM Aviation Weather can be a great help with obstacle and weather avoidance. But if you’re not instrument-rated, -current, and -proficient (and autopilot-equipped), your workload, stress, and risk can easily take over.

Milling around in rotten conditions near the surface is one thing. Other challenges can crop up at altitude. It may have occurred to you just how you’d be able to judge your distance from those 1,000-above, 500-below, and 2,000-horizontal cloud separation minimums. There won’t be any signposts or official observations up in cruise flight; you’re the meteorologist now. Of course, metars, automated observations, terminal aerodrome forecasts, airmets, sigmets, and other sources can fill you in, but these can be moving targets when fast-moving weather systems and other sudden changes are at hand. This means you’ll have to eyeball your distance from clouds. Which can leave you trapped on top of a cloud layer, or running a squeeze play between layers.

Cruising in clear skies on top of a cloud layer can give you a great feeling, but at some point you’ll have to descend to your destination. That means you’ll face instrument conditions on your way down. That, or start diverting to suitably large gaps in the clouds that will let you descend in VFR conditions. A 180-degree turn can be another option. 

Then there’s the chance that cloud tops rise, forcing you to try to outclimb them. Outclimb a young thunderstorm’s towering cumulus? Not likely. It can be difficult to judge the growth rate of a climbing cloud layer or storm cell, but yes, there’s an app for that. It’s called Cloud Topper. It converts your camera into a sight level, letting you know if your flight path will let you clear any buildups, or not.

To sum up, VFR minimums are the lowest limits for legal VFR flying and can be useful in negotiating around familiar airports. But don’t think of them as carte blanche to come up with home-grown instrument approaches or departures. That said, the regulations do recognize that things can turn dire. FAR 91.3(b) gives pilots facing an inflight emergency the authority to “deviate from any rule of this part to the extent required to meet that emergency.” Just be ready to file a written report if one is requested.

In the event of two-way radio communications failures, AIM 6-4-1 also supports pilots in trouble by saying, in part: “It is virtually impossible to provide regulations and procedures applicable to all possible situations associated with two-way communications failure…When confronted by a situation not covered in the regulation, pilots are expected to exercise good judgment in whatever action they elect to take. Should the situation so dictate they should not be reluctant to use the emergency action contained in 14 CFR Section 91.3(b).”

So, while the regulations may mean well, traps await the unwary.

Thomas A. Horne is a former editor at large for AOPA media and the author of Flying America’s Weather.